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Global Wind Power Potential
Posted by Gail the Actuary on September 5, 2011 - 1:40pm
This is a guest post by Carlos de Castro, a professor of Applied Physics in the University of Valladolid in Spain. Carlos is the lead author of an article that was recently accepted by Energy Policy called, "Global wind power potential: Physical and technological limits." The article is behind a pay wall, but Carlos was kind enough to write a summary of the article for us.
Global wind power potential: Physical and technological limits
Cite: De Castro C. et al. 2011. Global wind power potential: physical and technological limits. Energy Policy. Doi:10.1016/j-enpol.2011.06.027
Received 5 November 2010; accepted 13 June 2011. Available online 29 June 2011.
Abstract:
This paper is focused on a new methodology for the global assessment of wind power potential. Most of the previous works on the global assessment of the technological potential of wind power have used bottom-up methodologies (e.g. Archer and Jacobson, 2005, Capps and Zender, 2010, Lu et. al., 2009). Economic, ecological and other assessments have been developed, based on these technological capacities. However, this paper tries to show that the reported regional and global technological potential are flawed because they do not conserve the energetic balance on Earth, violating the first principle of energy conservation (Gans et al., 2010). We propose a top-down approach, such as that in Miller et al., 2010, to evaluate the physical-geographical potential and, for the first time, to evaluate the global technological wind power potential, while acknowledging energy conservation. The results give roughly 1TW for the top limit of the future electrical potential of wind energy. This value is much lower than previous estimates and even lower than economic and realizable potentials published for the mid-century (e.g. DeVries et al., 2007, EEA, 2009, Zerta et al., 2008).
Our calculations:
We use a top-down methodology based on six stages. The base data is the kinetic energy contained in the atmosphere, and this amount is restricted by several constraints that subtract the energy that cannot be transformed into electricity. These constraints are:
1. The energy of the lowest layer of the atmosphere, f1, P0(h < 200) = f1·P0
Estimates of the total kinetic energy dissipation in the atmosphere vary from 340 TW to 3600 TW. We take an intermediate value of P0 = 1200 TW as our starting point. The fraction of that energy that is available in the lowest 200m, f1, can be estimated via different methods taking into consideration 1) changes in energy density with height; 2) residence time of surface air masses or 3) dissipated power of the Atmospheric Boundary Layer. All three methods yield similar values near f1=0.083. Thus the power dissipated in the lower 200m of the atmosphere (accessible to windmills) is calculated as: f1·P0(h < 200) = 100 TW.
2. Reachable areas of the Earth (geographical constraint), f2. PG = f1·f2·P0
The Earth's surface is not uniformly suitable for kinetic energy extraction. Deep sea areas (more than 200m deep), areas permanently covered by ice, etc., can be excluded as uneconomic. Thus ¾ of the Earth’s surface is not suitable for wind farms. On the other hand, the windiest continent is Antarctica, and wind has a lot more energy over the deep seas than on the ground. We could, therefore, easily estimate that less than 80% of the energy will be lost because of these geographical restrictions.
f2 < 0.2
3. Percentage of the wind that interacts with the blades of the mills, f3
We estimate than a farm could catch less than approximately 30% of the kinetic energy that goes through it (considering the space among mills, a wind front of 200 meters high and mills of 100 meters in diameter), because the rest will simply never interact with the blades of the mill. Therefore:
f3 < 0.3
4. Areas with reasonable wind potential, f4
Even in locations accessible for wind parks, we consider that the mills will be situated in areas of class 3 or higher. Approximately half of all the kinetic energy of the geographically accessible areas are in areas of class 3 or higher, then we have: f4= 0.5
5. Percentage of energy of the wind speeds that are valid to produce electricity (not too little or too much velocity), f5
Wind turbines do not perform equally efficiently at all wind speeds. On average, modern wind turbines have an energy conversion efficiency of < 50%. We estimate that future designs will be able to improve this ratio and use three quarters of the energy that interacts with them, but not much more, therefore: f5 = 0.75
6. Efficiency of the conversion of kinetic energy into electric energy, f6
The maximum theoretical efficiency of a wind turbine (power output)/(power in wind) is known as the Betz limit and has a value of 0.59. If we assume than in the future the losses relative to the Betz limit (front kinetic energy to net electric energy) will only be 15% (at present losses are >30%) then: f6 = 0.5
Therefore: PT = f1·f2·f3·f4·f5·f6·P0 ~ 1TWe
Our conclusions:
The global assessment of the technological potential of wind power to produce electricity, based on the top-down approach, shows quite different results to those of previous works. The technical assessment potential that has been obtained is one or two orders of magnitude lower than those estimated by other authors. This means that technological wind power potential imposes an important limit on the effective electric wind power that could be developed, against the common thinking of no technological constraints by economic, ecological or other assessments.
According to the World Wind Energy Association, the electrical wind power produced today is ~0.045 TW and this type of energy is growing at an annual rate of > 25%. If the present growth rate continues, we would reach the 1 TW we estimated in less than 15 years. Therefore, probably in this decade, we will see less growth than we saw in the previous decade.
This limit poses important limitations to the expansion of this energy. Since the present exergy consumption of all energies is ~17 TW, it implies that no more than 6% of today’s primary energy can be obtained from the wind.
Furthermore, if the electric wind power of the world were to approach 1TW, we could generate a new class of “tragedy of the commons” with the necessity of the international regulation of rights to winds. Without an effective regulation, in a medium-term future, we will see “wind park effect and wake effect” on a global scale, making new and old installed parks less efficient.
Global assessment of potential energy based on bottom-up methodologies has been used for renewable energies such as tidal, wave or geothermal.
A top-down review of the global assessment of potential energy from these renewable sources may be necessary in order to obtain the best estimation for the top limit of primary energy that our society is able to use in a sustainable
Some of our References
These two papers use bottom-up methodologies being criticized:
Archer C. L., M. Z. Jacobson, 2005. Evaluation of global wind power. Journal of Geophysical Research, vol. 110, D12110.
doi:10.1029/2004JD005462
Capps S.B., C.S. Zender, 2010. The estimated global ocean wind power potential from QuickScat observations, accounting for turbine characteristics and sitting. Journal of Geophysical Research. Vol 115, D01101, 13PP, doi:10.1029/2009JD012679
These two papers calculate the power of the wind in the atmosphere that we use for our top-down approach:
Peixoto, J. P., Oort, A. H., 1992. Physics of climate. American Institute of Physics, 1, 379–385, 1992. 109
Sorensen, B., 2004. Renewable energy: its physics, engineering use, environment impacts, economy and planning aspects. Elsevier Acad. Press.
This paper gives a theoretical discussion of why bottom-up methodologies violate the first principle:
Gans, F., et al., 2010. The problem of the second wind turbine—a note on a common but flawed wind power estimation method. Earth System Dynamics Discussion 1, 103–114. doi:10.5194/esdd-1-103-2010.
This paper discusses why the "solution" is not the hypothetical energy transfer of wind from the upper layers of the atmosphere:
Wang, C., Prinn, R.G., 2010. Potential climatic impacts and reliability of very large-scale wind farms. Atmospheric Chemistry and Physics 10, 2053–2061.
This paper discusses the wake effect on a local scale:
Christiansen, M.B., Hasager, C.B., 2005. Wake effects of large offshore wind farms identified from satellite SAR. Remote Sensing of Environment 98 (2–3), 251–268 15 October 2005.
More Information
More details and more extensive references can be found in the original copyrighted version of the paper, Global wind power potential: Physical and technological limits, available from Energy Policy.
Contact
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License
This work is licensed under a Creative Commons Attribution-Share Alike 3.0 United States License.
Thanks, Carlos, for bringing your paper to our attention. The approach of your group is an interesting one.
How did you get the idea of looking at things this way? What made you think that the expansion capability of wind might be limited?
I also have a few questions;
This seems to be an arbitrary selection of the key input into the entire process. Why was 1200 TW selected (with citations, please)?
How are these correlated with selective siting methods, such as ridgetops or offshore? Such siting preferences will always improve the energy density of a random, average estimate.
Again, an arbitrary, seemingly random value is set forth as yet another premise with no support.
f5 and f6 both seem to be focused on the efficiency of converting wind energy into usable energy. f6 is labeled as the electrical conversion factor, but then is described as the Betz limit, which is the conversion of wind energy into usable mechanical energy, which is what is addressed by f5. Either combine them, or describe the factors in an unambiguous manner (such as f6 being the conversion efficiency between mechanical and electrical energy).
I can't say I have much confidence in the conclusion when multiple premises themselves beget little confidence.
The bottom up analyses look at potential sites and the wind strength/frequency at turbine height, among other variables. IMO, the bottom up approach is far more refined than vague generalities with little to no supporting rational (and "it seems" is not a rational).
I suspect that the analysis is actually more wrong than you posit above. For one thing, it suggests that the total wind power potential of planet Earth is on the order of what previous studies have calculated for the state of Texas.
Essentially, the authors posit that the energy extracted from wind is "lost", and isn't e.g. just shifted as an elevation of the wind shear distribution in the lower atmosphere. This ought to be easily tested, such as before-and-after measurements of wind speed vs. altitude upwind and downwind of large wind farms. The hypothesis, if true, would show a substantial and lasting decrease in available wind energy for long distances downwind of a wind farm.
AFAIK, measurements show that the effects of wind turbines fall below the threshold of detection within about 10 rotor diameters downwind. Perhaps this is not true of large wind farms which extend their influence both in breadth and depth, but only data can support or refute it.
I think that you have pointed out the flaw in this paper. The key piece of data is to measure the mixing between wind farm wakes and the atmosphere just above. It is believable that measurable slowing of the surface winds could be caused by very large wind farms. It is not believable that there is no mixing as this paper posits.
Yes, there is a mixing, but:
In order to regenerate the energy loss by the wake effect on a global scale, only a huge kinetic energy transfer from above the windmill atmospheric layer could partially justify a bottom-up
approach. But Wang and Prinn (2010) (see also Keith et al., 2004) use a general circulation climate model and show that the kinetic energy per unit mass in the atmospheric boundary layer is
reduced by more than 10% in order to generate 5 TW of electric power globally.
In simpler terms: the more dissipation the less kinetic energy the less energy transfer from ABL.
Climatic change and land use change (mainly deforestation and reforestation and buildings and urbanization) are causing changes in the wind velocity distribution over the Earth. Wang
and Huang (2004), give a 20% increase of the wind energy input to the surface waves in the last half century and, on average,terrestrial near-surface winds have slowed down in recent decades (McVicar and Roderick, 2010); human induced surface roughness changes are effectively reducing wind energy and
changing wind distribution, so windmills will also do this.
Therefore: if we add roughness the winds change and go to "free places" like the seas.
All these facts should be considered when using bottom-up methodologies, since they would significantly reduce the effective density of windmills in the suitable areas; but these considerations are not found in the authors (except for Miller et al. 2010 who use a top–down methodology). These studies assume that the perturbation that a wind farm produces is negligible compared to the global amount of resource; but those bottom-up methodologies are not compatible with global data of kinetic energy present in the atmosphere and therefore violate the principle of energy conservation (¡!) as Gans et al. (2010) does explicitly on theoretical grounds based on the wake effect, and Wang and Prinn (2010) does implicitly, using a 3D general circulation model.
Reduced wind speeds are also a consequence of GHGs, which decrease the heat loss at the pole and the ΔT which drives heat transport.
If increasing surface roughness cuts wind speeds, there is the potential to also cut the rate of heat transport to the poles and reduce the out-sized effect of AGW there.
I wouldn't be so sure. Because of the corriolis effect, rather than winds flowing directly form high pressure to low pressure, they get deflected, and to a high degree flow at right angles to the pressure gradient. It is resistive effects, that allow some drift from high to low pressure. So a somewhat rougher boundary layer, will have some effect, but I don't think straightforward intuition will work here. Rather you would want to play with a weather model that you could adjust roughness heights on, then come to conclusions, after you've seen how the system responds to changes.
The methodology is transparent anyway. Why don't you plug your own figures in (with reasoning) and give us your answer ? Then compare and contrast with what is needed for BAU.
If wind power was going to be the answer to world's problems, it would have to doable by all the countries of the world, including the Bangladeshis and Somalians. It is immediately apparent that they cannot afford to do it, though their need is desperate.
"Just build an HVDC grid" it is said, to overcome the distribution losses of generators all across the country trying to feed the cities. But at what financial and energetic cost and at what disruption to the countryside?
Trees cause drag and slow the wind, so why not cut down all the trees and replace them with wind turbines - you know, something USEFUL.
And all so we can continue to follow our unsustainable lifestyles sustainably.
compare and contrast with what is needed for BAU.
A renewable grid isn't BAU.
If wind power was going to be the answer to world's problems, it would have to doable by all the countries of the world, including the Bangladeshis and Somalians.
Why? Fossil fuel isn't.
build an HVDC grid" it is said, to overcome the distribution losses of generators all across the country trying to feed the cities. But at what financial and energetic cost
Just do a quick google search, you'll find it's affordable. IIRC, 1,000km costs about $.25/Wp.
When was wind power going to be the only answer? It is part of the answer. Wind, solar, wave, more efficient distribution, storage, and to your point, conservation/more efficient use of energy are all going to have an important role.
Your point that the methodology is transparent and open to modification is quite valid. I think this methodology is too conservative while some of the other projections are way too optimistic. Still, I am not sure anyone would give up a Terawatt of production capability that has no carbon footprint.
My question was: How wind mills, reforestation, buildings, etc, can affect the winds and how this will affect the ecosystems. I was searching the bibliography about the total disipation of kinetic energy (roughly 1000TW) in the atmosphere and I remember the claims that we could trap more than 100 TW in mills. It is obvious than something was wrong.
A number of solutions to deep water foundations are being explored, with some already in use by oil rig platforms;
http://www.nrel.gov/docs/fy10osti/47534.pdf
We consider the first 200m depths, see your second figure.
200 meters seems a bit arbitrary. The Wikipedia article mentions one project at 320, and I don't see a particular reason for a hard cutoff at any particular depth.
So often, things look like limits when they're just things we haven't done previously because we didn't need to.
Then we should use proven wind power reserves, unproven and so on. Just to give a sense of perspectives. Unproven for some is like walking on water and for others its like drilling in antartica.
This floating WT-pilot is already in 200 m of water ....
claim ;The wind turbine can be placed at ocean depths of between 120 and 700 metres.
more here ; http://en.wikipedia.org/wiki/Floating_wind_turbine
Small note: the wikipedia article says that it's in 220 m of water.
I would think that an article such as this would want to use an outer limit, not a limit which has already been passed...
Diffuser Augmented Wind Turbine draws in more air and increases efficiency. It is claimed that this design is not limited by the 59% maximum efficiency for an ordinary turbine and generates about three times more power than an ordinary turbine of the same blade diameter.
The devil is in the details, and such Diffuser claims almost always use the wrong yardsticks.
Of course they give better numbers, relative to the same blade diameter. - but you COULD have made much larger blades, for the SAME wind-loading, and SAME Elevated-kg costs.
So they fail to do a real comparison, which is the kW per wind-load-area (these things DO need to survive storms!), and the kW per Elevated-kg. (Foundation and tower costs are otherwise merely glossed over).
One you do this, you see Diffuser claims fail basic engineering reality tests, which is why they never make it off the investment brochures.
That certainly is an interesting result with consequences. If the analysis is correct, calls for a "prosperous way down" (HT Odum) "powerdown" or "long descent" should receive increasing amounts of attention. In this regard, Greer's Ecotechnic Future cannot be recommended enough - a review is available here if anyone's interested - http://ubuntuone.com/p/1FBU/. Any ideas of the best assessments for solar?
One technical question: Did you factor-in the likelihood of airborne wind generators? http://en.wikipedia.org/wiki/Airborne_wind_turbine
If so, how do they compare in importance to conventional wind-turbines? If not, why not?
Reading Smil's Energy Transitions at the moment. This illustrates the century-long timescales that transitions from one primary energy source to another take (theory, design, infrastructure, commercialisation phases can take over a decade each!) So I don't blame you if you only include currently commercialised technologies.
Many thanks for making this important work available to the public.
Robin
They did not:
IMO, KiteGen, Makami Power, et al have far more potential than terrestrial wind turbines.
Thanks.
Although there are no commercial turbines higher than 200 m, some scientific literature
is speculating with devices that would trap the energy at high altitudes (>500 m) (Archer and Caldeira, 2009; Fagiano et al.,2009; Roberts et al., 2007).
These future technologies would be subject to many of the restrictions that we have calculated for low heights, and the principal restriction would be given by the factor f3, the energy of
the wind that interacts with the blades. All of the designs of these technologies are attached to the ground, and the ones with greater perspectives are the helicopter and tie types.
Since the wind fluctuates in direction and intensity, these mobile designs would need an area of operation and security a lot larger than the fixed windmills.
For these designs, f3 can not be greater than 0,0001, and because we will also have the rest of the ‘f’ factors, then this kind of contribution will be very little.
Starting with your P0 of 1200W
F2: this value should be higher as kite-gen type apparatuses can access more of the earth. Let's say 0.5
F3: same
F4: wind energy is far more constant at higher altitudes Should be closer to 1
F5: again, should be higher at higher altitudes. Let's say .9
F6: same
6.75TW. That seems like a more reasonable figure IMO.
F2=0.5 means that you could access 50% of the entire Earth. a kite attached to the seas? Sci-fiction.
F3= same (for kite type take 0.0001)
F4=1, but obviously is extremelly optimistic (we use the best places for economical reasons)
F5=0.9 again very very generous.
F6 = same=0,5, generous (probably much lesser than mills, and with a bad EROEI)
Therefore, if P0=1200TW you get 0,027TWe for kite-gen type apparatuses...
How is it that a kitegen attached to the seas is science fiction? They generate 50x the power from a given mass of materials than their traditional HAWT brethren. Automated takeoff and landing on the ocean is feasible IMO
Look at Makani's website: http://www.makanipower.com/concept/makani-m1/
0.027TWe=27GWe=27,000MWe=~54,000 Makani M1 style AWTs with a capacity factor of 50%. The surface area of the earth is ~196,000,000 square miles. You're saying that the absolute maximum potential deployment of such AWTs is 1 per ~3,700 square miles?
Assuming that rudimentary controls are used and they are deployed at 200m, 16 M1 style AWTs per square mile is perfectly feasible.
What would they be attached to at depths over 5000 ft? 10,000 ft?
How would the power be transmitted to shore?
Small floating platforms tethered to the bottom. We already do this with buoys. Power could/would be aggregated and then sent to shore with ultra-high voltage DC.
I'm not saying that it's a panacea or a silver bullet but that it's a silver BB. HAWTs are already proven. The engineering required to deploy AWTs on land or even at sea is well within our grasp (indeed, we've already developed most of the technologies individually).
I would suggest, based on decades of migrating technologies from applied research to full deployment, that some HAWTs have made it to the early demonstration phase. Since I have not been following their progress closely, I'd be interested to see if any have yet made it to actual pilot phase, where they are live 24/7 over a period of at least 30 days, with a complete follow-on analysis.
You mean Verticals, right? Horiz. is the standard.
I suspect that verticals will tend to prove their worth in the most remote and harsh environments, as they are able to be engineered with far less need of maintenance than HAWT's with their single chain of stress-points.. Tower, Pivot Axis, Hub and Blades.. high-energy, high-maintenance.
Actually, I'm referring to high altitude turbines, like kites and 'floating' turbine sets;
There are places one does not wants to slow the wind because it is moving polluted air to someone else's backyard. For example Mexico City and China.
Sounds a good reason to slow it. Maybe that will make them want to do something about it.
NAOM
1 TW from all the wind in the world. That's pretty sobering.
I hope I die long before we live in a world where people can be prosecuted for stealing other people's wind. It's already bad enough that - for example, people think ocean-life is their "fish stocks" and now that they have "depleted their fish stocks by 90%" i.e. driven many species to extinction and undone more of the complex web of life which is hundreds of millions of years old and irreplaceable - that nations have drawn up quotas for each other and have a consensus on who does how much destruction.
Have the authors of this paper heard of floating windmills?
http://en.wikipedia.org/wiki/Floating_wind_turbine
It's conceivable that autonomous floating windmills can operate on deep-seas and, using inbuilt equipment, electrolyze sea water into hydrogen and oxygen, which can then be compressed and stored until they are harvested. I believe there is a similar pilot project just off the coast of Maine which was funded by Matt Simmons.
The deficiencies in the quoted analysis aside, I think the takeaway message is "go nuclear".
There are other potential takeaway messages like "consume less".
That won't suffice.
Reducing consumption may not suffice ("For what?" is another question.) But I am of the opinion that reducing consumption is a simpler, lower cost, lower risk, more sustainable, more environmentally friendly, more distributed, more flexible and more immediately applicable solution that nuclear.
I'm not saying that reducing consumption will solve all of our problems. I'm just saying that it is the low hanging fruit that few seem to be able to see and we should start there first.
We draw 15 TW globally today, or 2 KW/capita. It seems 5 KW/capita is the norm for reasonably frugal high-tech societies such as Japan and Great Britain, while 10 KW/capita is the norm for North America. Considering the global population will likely peak at some 30-40% higher than today and all should be high-tech, we arrive at 15*(5/2)*1.4 ~= 50 TW.
Of course, with further consumption reductions (in the 50 TW, a halving of North American consumption is already assumed), perhaps we could arrive at less, but 1 TW wind seems too little to make much of a difference. At 10 billion people, that would be 100 W/capita. Today, Bangladesh is lowest at 200 W/capita, and I would say that their standard of living is inadequate.
Also, to reduce consumption can very well be more complex, higher cost, higher risk, less sustainable and less environmentally friendly than nuclear. It depends on the particular consumption reduction. To throw out a working product (a car, a house, a fridge...) and buying a new, more energy efficient one is often much worse than creating some more nuclear energy, for instance.
Btw, we have been picking low hanging fruit since the 70-ies, but it does not suffice and will not suffice. We'll be sorry (we should already be sorry) that we didn't simultaneously expand nuclear power.
but 1 TW wind seems too little to make much of a difference.
Nuclear at 0.285 TW (2500TWh/8.76Mh) is 3.5 times smaller than yours 'too little to make a difference', unfortunately.
Also, to reduce consumption can very well be more complex, higher cost, higher risk, less sustainable and less environmentally friendly than nuclear.
According to your reasoning, Europe would be more sustainable if it doubled its electricity consumption by introducing more inefficiency (same as the US) and extremely build up nuclear and its grid to be able to cope with the increased power demand.
To throw out a working product (a car, a house, a fridge...) and buying a new, more energy efficient one is often much worse than creating some more nuclear energy, for instance.
Actually a new efficient fridge will save about 500 kWh per year compared to an old one. Letting an old fridge run for another 10 years until it breaks by its own would require to completely fill the fridge with coal 20 times over with 3 tons of coal (in order to produce that wasted electricity with coal).
Besides one who believes in free markets would probably favor a carbon tax over any subsidies. A carbon tax would automatically favor cheaper and faster alternatives (primarily efficiency measures and renewables) over nuclear, unfortunately:
http://www.weeklystandard.com/articles/nuclear-socialism_508830.html
I agree, nuclear doesn't make much of a difference either, at perhaps 5% of primary energy, and will make even less of a difference in 2030 if it isn't expanded quite a bit.
No, that's not according to my reasoning. Re-read and apply better reading comprehension.
Why? Because nuclear power is so heavily regulated in the US that a moderate carbon tax won't allow nuclear to overcome the obstacles? Otherwise I cannot find any reason at all - to me a carbon tax is neutral. Your link doesn't support your claim.
Why?
The capital costs and construction times for new nuclear are simply too high compared to cheaper and faster carbon reduction options, unfortunately: http://www.rmi.org/rmi/Library%2FE09-01_NuclearPowerClimateFixOrFolly
A study from McKinsey which underestimated new nuclear capital costs by over 50% arrived to a similar conclusion, unfortunately:
http://www.mckinsey.com/en/Client_Service/Sustainability/Latest_thinking...
Which is also why there are comparatively few new nuclear power plants being built despite generous subsidies:
http://www.weeklystandard.com/articles/nuclear-socialism_508830.html
New nuclear power pre-Fukushima-offers in North America are close to $8/W:
www.thestar.com/comment/columnists/article/665644
www.time.com/time/printout/0,8816,1869203,00.html
www.npr.org/templates/story/story.php?storyId=89169837
www.ocala.com/article/20101026/ARTICLES/101029758?p=2&tc=pg
While wind turbines are meanwhile below €0.90 /W:
http://bnef.com/PressReleases/view/139
In addition, wind power doesn't require any high decommissioning costs, no uranium mining, no uranium imports, no costly repositories, no costly taxpayer-funded R&D, doesn't pass liability to the taxpayer, is built quickly and has lower operating costs.
http://www.guardian.co.uk/world/2008/jul/10/nuclear.nuclearpower
http://www.postandcourier.com/news/2008/aug/27/nuclear_surge_needs_waste...
http://www.progress.org/nuclear04.htm
http://www.world-nuclear.org/sym/2001/fig-htm/frasf6-h.htm
Furthermore, distributed wind farms are insensitive to war, earthquakes and tsunamis:
http://www.energydigital.com/renewable_energy/wind-farms-vs-nuclear-ener...
and wind farms do not require any cooling water at all:
And wind power also doesn't require tax-payer paid organizations such as Euratom and IAEA to be promoted.
In fact Austria without nuclear power pays almost double as much on Euratom than on its own wind power:
www.igwindkraft.at/index.php?mdoc_id=1009697
Now you're bombing us with your list of cherry-picked links again and parroting the same nonsense as you always have. Unfortunately, the misinformation you present doesn't answer my "why?". You're welcome to try again.
Can you supply us with links which demonstrate nuclear cheap to build?
How about fast to build?
Or a permanent solution to nuclear waste disposal?
Please, no nuclear industry low-ball numbers lacking the details so one can tell what has been included and excluded.
Please, no "China builds them overnight" stuff. We ain't China, in our country citizens have input to the process and nuclear construction companies can't command supply chains to run in their favor.
Please, no "Just encapsulate in glass and stick 'em in the basement. Someone will figure out a real solution later.".
And no very best case fantasies. No "Once we figure out how to make this work" stuff, real solutions, solutions in hand. No "Tiny reactors in every neighborhood" fantasies. Factory built reactors would only get affordable were they to be built in very high numbers, economy of scale does not arrive at a hundred units.
Oh, and identify a few hundred communities which would allow a reactor to be built in their backyards. Make sure they all have access to cooling water.
In the US, nuclear IS expensive and slow to build, and that's precisely what I'm pointing out. You should sort it out. If the Chinese can build the AP-1000 with little effort, then so should you.
A permanent solution to waste disposal, for instance, is the Swedish KBS-3 method.
Hand waving does not provide substantial answers to the questions which I asked.
If the Chinese can build the AP-1000 with little effort, then so should you.
You know that's what you've called hand-waving, right?
I've seen a lot of accusations of Chinese subsidies: free land, very low priced capital, price-controlled electricity & fuel, lack of pollution controls, etc, etc.
China actually does not control the price of coal, and utilities have cut back generation because their mandated price is no longer paying for their free-market fuel.
The beauty of nuclear power is that fuel can be stockpiled for years, not weeks. Integral Fast Reactors or thorium MSRs could stockpile fuel for the entire plant lifetime at the time of construction.
utilities have cut back generation because their mandated price
I have the impression that a large % of Chinese oil imports are caused by diesel backup generation for manufacturing - I'd love to see stats.
Isn't that hand-waving as well?
Well, it's one step beyond hand-waving: providing specific ideas, but without evidence for each.
Seems like a reasonable step forward in a debate like this.
I can, unless you rule out South Korean numbers:
Other pages of this document can be found at:
Soon Chul Yun - Introduction to Korean Nuclear Industries
Page 15-16-17
J,
I think "anyone"'s argument is clear: he's arguing that wind is cheaper pre-carbon tax, so it's cheaper even with a carbon tax.
If you disagree, I'd be curious to see what you feel is the best cost comparison. Of course, it would need to match comparable costs: either both in or outside China.
As I said elsewhere, China builds nuclear for $2/W and are pressing that downwards. To compete, wind would need to be built for $2/3 = $0.66/W. I don't think they can, since hardware costs should be similar in China to our western costs.
And again, even if wind is as cheap, it is still intermittent and so doesn't scale very well.
IAWTP.
China builds nuclear for $2/W
See my comment above.
even if wind is as cheap, it is still intermittent
Again, that's not really supported by evidence - you're going on intuition.
I've shown you studies that show that wind and solar can reach 35% of the grid at very low cost. There are no studies looking at higher levels - such studies simply haven't been needed.
Still, wouldn't you agree that your intuition has been surprised in the past, by things like wind price parity in the US, and the 35% result mentioned above?
The "very low cost" for 35% wind and solar is not really supported by the study you presented, if I remember correctly. There were a lot of stuff that needed implementation to get it there, and the costs, as I remember them, weren't really quantified. Yes, the grid could swallow the wind without big modifications, but you did need to cut down on utilization of other plants, do DSM and such.
Also, that wind can be built cheaply is just one side of the equation. The other side is how much you are paid for the wind electricity. At 25% penetration, you will hardly be paid at all, since there will be too much electricity when the wind is good.
Yes, the grid could swallow the wind without big modifications, but you did need to cut down on utilization of other plants, do DSM and such.
The grid already has flexible plants with relatively low capacity factors in order to deal with flexible demand.
More wind and PV primarily reduces natural gas consumption and saves water:
http://www.reuters.com/article/2008/04/15/spain-water-idUSL1579694720080415
not really supported by the study you presented
It's worth reviewing it again:
""The electricity grid in the western United States could support up to 35% of wind and solar power by 2017, without extensive additional infrastructure, according to the National Renewable Energy Laboratory (NREL).
The US Department of Energy’s research agency issued a study that said the target was “technically feasible” – but would require key changes in how the electricity network is operated in the mountain and southwest states.
Up to 30% wind energy and 5% solar energy penetration could be achieved on the grid with a better coordination of utilities’ distribution activities across a much wider geographic area, the research suggested.
It also recommends operating a schedule of generation or sales more frequent that the current hourly system.
This would allow the system to react to the changes in transmission level from wind or solar projects.
Dr. Debra Lew, NREL project manager for the study, explained: “If key changes can be made to standard operating procedures, our research shows that large amounts of wind and solar can be incorporated onto the grid without a lot of backup generation.”
“When you coordinate the operations between utilities across a large geographic area, you decrease the effect of the variability of wind and solar energy sources, mitigating the unpredictability of Mother Nature,” added Dr Lew.
Western US
The Western Wind and Solar Integration Study offered a first look at how a significant amount of renewable energy could be integrated into the grid in the western US.
It followed a study published in January on the impact of wind farms on the grid east of the Rockies (see this BrighterEnergy.org story).
The Western study looks at the power system operated by the WestConnect group of utilities in the mountain and southwest states.
This group includes Arizona Public Service, El Paso Electric Co., NV Energy, Public Service of New Mexico, Salt River Project, Tri-State Generation and Transmission Cooperative, Tucson Electric Power, Western Area Power Administration, and Xcel Energy.
The research stated that were these utilities to generate 27% of their electricity from wind and solar sources across the Western Interconnection grid, it would cut carbon emissions by 25% to 45%.
It could also decrease fuel and emissions costs by 40%, depending on the future prices of natural gas, the study claimed.
The study called for better use of wind and solar forecasts by utilities, and pointed out that more efficient use of the current grid infrastructure would mean less new transmission systems need to be built."
http://www.nrel.gov/wwsis
No DSM, no large scale backup, little new transmission.
you did need to cut down on utilization of other plants
Well, that's kind've the whole point, isnt' it??
The other side is how much you are paid for the wind electricity
That's partly a boring administrative problem, and partly an economic arbitrage problem. It reflects the basic problem of excess night time generation (shared with nuclear) and variance. It certainly needs work, I agree.
Up to 30% wind energy and 5% solar energy penetration could be achieved on the grid with a better coordination of utilities’ distribution activities across a much wider geographic area, the research suggested.
Based on the installed PV-Power in Bavaria (December 2010), Bavaria has already reached 8% PV in the Bavarian grid this year:
http://www.solarserver.de/solar-magazin/nachrichten/aktuelles/2011/kw12/...
http://www.photon.de/photon/photon-aktion_install-leistung.htm
If Bavaria can deal with 8% PV (and will probably top 10% PV by next year), the US should be able to deal with more:
1. The US has a much larger area.
2. The US has lots of air conditioning (DSM) and Bavaria doesn't.
3. By the time the US would reach 10% PV in the grid (if at all), parking lots will already have lots of electric cars (DSM).
Again as I said elsewhere: If nuclear was significantly cheaper than renewables as you (contrary to the facts) claim it to be, China would not add far more renewable capacity than nuclear capacity.
In 2010 China installed 29 GW of new renewable capacity (18.9 GW of new wind) and 17.5 GW of new solar hot water capacity (instead of installing electric/nuclear powered water heaters) and only 1.6 GW of new nuclear: http://www.ren21.net/Portals/97/documents/GSR/GSR2011_Master18.pdf
Again you spam us with the same quote and link.
No, dear anyone, costs is not the sole determinant of ramping speed.
Fact is: China had over 30 years to significantly increase its nuclear share and it hasn't done so despite the fact that nuclear is supposed to be very inexpensive.
Since they have had nuclear subs since then? (Were those Soviet or indigenous?)
The question is whether wind or nuclear is more expensive (and scaleable) in China. Neither have been scaled for long there, although both have been theoretically possible for ages. That's due to coal being cheaper, and it's only now that growth and climate concerns have spurred interest in other options.
Your objections seem very puerile to me. I think the TOD community is too sophisticated to fall for your shallow analyses.
I'm flagging the repeats. They're spam, pure and simple.
Ah, yes, the Rocky Mountain Institute. An organization which has predicted dozens of the last zero commercial nuclear events with fatalities, and hand-waves the questions of how remaining energy demand can be supplied sans nuclear even if its other prescriptions are followed.
Newspaper articles are the best you can do for citations? If TOD had a comment-rating system like the old Slashdot but tailored for the particular needs here, that one would rate all of:
-1, Unreliable
-1, Sandbagging
-1, Repetitive/Spam
Then why don't you simply deliver proof regarding cheap new nuclear power (and uselessness of efficiency and renewable energy measures) instead of ad-hominems?
China's build rate and costs. 400% "NRC tax", cited elsewhere in this thread.
Straw man. Flagged.
China's nuclear build rate cannot even cover the yearly electricity demand increase in China.
This is your proof that new nuclear is supposed to be a low cost energy option?
According to your reasoning, no energy source in China is low cost, since no source supplies all of the increase. Again, you make no sense.
Actually, as opposed to your 'cheap' nuclear and as I already showed before renewable energies added close 50 GW additional capacity (electricity and heat) in China last year.
That "build rate cannot even cover the yearly electricity demand increase in China", as you put it. Why won't you just admit that your reasoning was faulty?
I should have said: "The nuclear build rate cannot cover the yearly electricity demand increase in China by far."
In order cover the 177 TWh extra electricity demand, China would have needed to install almost 20 times more nuclear capacity last year.
On the other hand renewable additions were able to cover over half of the increased Chinese electricity demand last year.
Some will consume less, some will say: "screw that, I want more electricity", and will build nuclear power plants.
Well price is reducing consumption more or less. Look at US gasoline consumption data. But consumption is the easier end to trim. Adding electrical production appears to be running into issues as far as I can tell, examining oil production and now China bottlenecked on coal electric power and taking diesel off the market to make electricity. Kind of smells like a problem.
Actually, what is easier is decided in the market. It produces a mix of new supply and demand destruction based on costs of those alternatives.
However, much energy production is surrounded by regulation that drives cost (extreme for nuclear), and this distorts the picture. At the same time, some energy doesn't fully pay for external costs - another distortion.
Actually, what is Profitable and Expedient is what the Market 'decides'.
There are a number of companies profiting from the TEPCO cleanup. Of course, much of that Profit in the Marketplace for ROV 'bots and plastic tents and filtration systems is going to be paid for by the Japanese Taxpayer.
Another Distortion.
The trouble with autonomous floating windmills is that you cannot get around the first law of thermodynamics. If the windmill is not anchored, then you have to use as much or more energy to hold it on station as it can generate from the wind.
Of course, you could put out a sea anchor and slow the drift down without consuming energy (actually, you could put water turbines on the sea anchor and generate even more energy), but eventually it would crash into the rocks the other side of the ocean.
You could put a keel on it and tack back and forth into the wind, but then you would have a windmill that tacks back and forth into the wind. It's not really a practical concept.
If you put it in the "Roaring Forties" of the Southern Hemisphere it would work really well, except that it would continue to circulate around the world, over and over again. You would have to build floating cities and floating factories to take advantage of it, which is not bad for a futuristic Sci-Fi movie (a utopian Waterworld) but not what the people currently living on land had in mind.
Rocky, I assumed that would be a given, when I hear of a floating windmill I automatically think of something like a semi submersible rig, so yes I imagine it would have to be anchored. Why would that be an issue?
Shox said autonomous floating windmills can operate on deep-seas.
If you have an anchored floating windmill, then the water must be shallow enough to anchor it, which rules out most of the world's oceans.
Apparently existing tech can go up to about 700m.
I think you just gave the Seasteading people something to chew on.
In all seriousness, the density difference between water and air means that holding position even with thrusters doesn't consume huge amounts of energy relative to the turbine output.
force = ρ(dV/dt)²
power = ½ρ(dV/dt)³
That's probably true. I didn't think of the implications of the density difference between water and air. It's probably not overwhelming practical but it might work in theory.
And then I got carried away with idea of free floating windmills in the Southern Ocean powering floating cities, but somehow that seemed more practical than a lot of the stuff that gets posted here. At least there would be no shortage of wind there.
I suspect the wind stress isn't the greatest worry. It is the wave action. The southern ocean can generate some pretty nasty waves.
But, I am not impressed by these proposals to generate fuel from ocean wind, then transport it to land. Sounds like too many expensive steps. Even offshore turbines in say 50M of water may have questionable economics.
If the wave action is good, spar-type wave-energy harvesters may make lemonade.
Making liquid fuel from mechanical energy is a rather silly thing to do. Making products with high embodied energy and relatively low shipping cost makes much more sense. If people really want the energy from halfway around the world, even far-out ideas low-orbit microwave power relay satellites might move it more efficiently than converting it to hydrocarbons.
Matt Simmons was proposing ammonia for at least a portion of the energy output from wind farms off the Maine coast;
http://www.oceanenergy.org/energysystem.asp
Not sure where that is going after he has passed.
So we can at most produce 22 times as much wind energy as we are producing now? This just doesn't feel right--right now only a very, very minute area of the earth has wind farms.
This is a pretty good argument.
My mistake, nevermind. Your argument is valid.
Of course it's a good argument. In fact it is an argument that completely obliterates this guys whole thesis.
I don't think we should do so, but really, if we put wind generators all over the great plains, the deserts, the continental shelves, the tops of all mountains, the Arctic and Antarctica (which will be increasingly inhabited as GW heats up)... it would only increase total output by a measly 22x?
It's ridiculous on the face of it. And of course there is no accounting for new technologies, even the tested ones. How about the ships that are already being assisted by wind? How about other floating devices? Kite structures?...
I happen to think we should do about 95% of what we nee to do by powering down and only about 5% building up renewable in order to get where we need to be--ff and nuke free.
But this is clearly just another of the many attempts of our dear actuarial friend to discredit alternative sources of power. I'm not sure what it is that irks her so about these technologies, but she apparently has never met one she didn't hate. So whenever you see some argument presented to you by her on this, directly or indirectly, it is best to come to it with a very suspicious mind knowing that there is always a very polemical, one-sided, hostile urge behind it.
That would tend to explain why my fisking of Michael Dittmar's error-ridden pieces was so ruthlessly and consistently censored. It doesn't matter if the ideology is wrong, it only matters if people get to see that it's wrong.
Was it his TOD article back in 2009 (republished in TR and elsewhere) that was gloomy on nuclear energy potential?
It was whichever one was published here in 4 pieces.
My rebuttal to his faulty (I'd say deliberately falsified) drive-by claim about another article some months later was also censored just hours after posting (and shortly before comments closed), and I've neither received an explanation from anyone why this was done nor even received a copy of my work to post at my own blog.
There's a great deal of willingness among the TOD editors to post whatever certain (highly but irrelevantly) credentialed doomers have to say regardless of how far they stretch or ignore the truth (and outrage decency thereby), but I believe that for TOD to publish rebuttals which address such stretches and falsehoods in the depth and tone appropriate to such outrageous abuses of decency would require outright coercion (too-literal colloquialism deleted).
The doomers believe that the existing fossil-fuelled economy will fail, down to the systems which bring adequate nutrition to billions of people; as a consequence, those billions are going to starve and very likely die. It follows that if there is any way to avoid this failure, it is a moral imperative to pursue it... or at least not suppress its pursuit, either by censorship or by propaganda. Series like Dittmar's are so full of factual and logical holes as to be indistinguishable from propaganda, and what has been done to me is certainly censorship. I hold the propagandists and censors responsible for the consequences, and I will point the people with torches and pitchforks in their direction when the time comes.
Excellent comments, thanks -- and disturbing ones if your accusations of censorship are true. (Are they? Perhaps we can hear from oildrum moderators?) And yes: it does not require censorship, if propaganda and biased reporting are thick enough.
The ethical dimensions of the things discussed here have not been given nearly enough attention. The "billions must die" meme has penetrated a surprising number of minds; it is almost invariably held with a bare minimum of critical analysis, if any.
I applaud your holding of the propagandists and (alleged) censors responsible for the consequences of their actions, and look forward to hearing more from you.
Only if you assume that the amount of wind power that can be tapped is proportional to the surface area devoted to wind farms. I.e., that tapping the wind at location X has no effect on wind at location Y. That's not the case.
The key factor in how much power can be sustainably generated from wind is not how much wind happens to be blowing across the world and any given moment, but rather on the rate at which wind is regenerated after being dissipated by turbulence, friction, and any wind turbines that happen to be in its path.
It's long bothered me that wind resource estimates are made simply from measurements of how much wind there is at available sites. There seems to be no regard for depletion of wind resources. But there's nothing magical about wind; when you take energy from it via a wind turbine, the energy you've withdrawn from the system doesn't just magically reappear. The wind is a kind of bank account of kinetic energy. Friction creates a steady leakage from that account, balanced by a steady income driven by differential solar heating of the atmosphere. It's the rate of income that ultimately determines how much can be tapped, not the instantaneous size of the account.
Yes, there should be careful studies of how much the wind is dissipated from large turbines.
This ain't it.
It just makes assumptions about this based on...apparently nothing.
See the posts near the top for more technical discussions of the shortcomings of the paper.
There's nothing magical about friction with the ground, either; wind energy withdrawn at 100 meters altitude isn't going to be dissipated against the landscape. It's not a question of whether than energy is going to be taken out of the air flow, it's a question of where and by what. It's going to happen anyway, so it might as well by something that's useful to us.
Very good point. Mountains and tress dissipate the wind and have done so for millions of years.
I find worrying about wind dissipation somewhat like worrying about rainfall water used to grow corn for ethanol.
In the case of water it either helps grow living things, evaporates or enters the ground. It is not really "consumed" as implied in the argument. It merely changes form for a while and is recycled.
Water is not like oil which takes millions of years to form in hard to get at places. The water cycle is relatively short and most of the earth is covered with it.
This is also true of wind. Only the whole earth is covered with air. A main characteristic of gases is that they expand and contract at enormous rates with temperature change compared to liquids and solids. So as long as the temperature of the earth is uneven wind is inevitable. And it will be uneven forever due to the earths rotation, axis angle, and water vapor over land and ocean among other things.
The wind may be slowed and energy dissipated by natural objects such as mountains or trees or by wind turbines. It doesn't matter. The forces driving the wind are coming from the sun and its uneven heating of the earth. These are permanent features of the wind system.
Mountains may rise and erode but the wind remains. Wind turbine dissipation of wind energy is nothing to worry about. Energy for wind comes from the sun. It can not be stopped. There is a new supply every day. And it costs nothing.
There is very little difference between solar energy arriving daily to drive wind and energy magically reappearing every day.
You can't get around the first law of thermodynamics. If you generate energy from wind, then you are taking energy out of the wind - over and above the energy that would be dissipated by friction with the ground. Wind turbines do disrupt the wind flow so the wind downwind from them is slower and has less energy than it otherwise would.
Mountains do have effects on the wind, but not what you might think. The best locations for wind farms are treeless areas in or near mountain passes, because the mountains on each side funnel the wind and create a "wind tunnel" effect that creates much higher wind velocities. Treeless areas are the best ones for wind farms because trees do dissipate the energy in the wind.
An example of wind energy effects: I know people who save money on gasoline by "drafting" large trucks down the highway - they tuck in close behind a big truck because it breaks the wind and saves them gasoline. This is not free energy, however. The truck drivers hate it because they can feel their truck slow down when a car is drafting them, and they know it is costing them fuel. There ain't no such thing as a free lunch, or free energy.
well actually the energy taken from the wind is "used" and produces heat which will... tend to make more wind as this energy is dissipated in the atmosphere. Not sure what the efficiency of this loop would be but it seems to me this analysis is missing this factor entirely.
That energy is currently used now though, so unless you are adding rather than replacing it doesn't count. If anything, replacing fossil and nuclear with wind would probably cool things overall.
To me it seems the truck is breaking the wind whether or not a car is drafting behind them. Would a car drafting behind the truck really slow down or have any other effect on the truck?
I think the net drag of the system, car plus truck is lower, than if they are well separated. Drafting if a well known technique in bicycle racing and touring. I wouldn't be surprised if the truck sees some increase in resistance, but it would be a lot less than the decrease the car sees. The real issue is safety. If the truck must stop quickly, a closely following car won't have time to react. You can get a minor benefit by following at a safe distance (say roughly 2seconds behind), but I don't think this is what you were considering.
Also notes geese flying in V shaped wedges, are exploiting group synergy effects w.r.t aerodynamic drag.
Geese in V formation are exploiting the wake vortices of birds ahead.
The drag on truck and car together is less than truck plus car separately. But it is more than the truck alone. Yes, absolutely the truck feels it and is paying for it in reduced gas mileage.
Also a safety problem? Absolutely!
Yes, about the geese. They have long since figured it out. Including the fact that the lead goose does extra work to make life easier for the others. Lead geese rotate out. The extra work of leading is shared by taking shifts.
--Gaianne
I'm intrigued. How does the car behind create a drag on the truck in front?
The details of aerodynamics are not exactly intuitive. But in tailgating, the car is being carried forward by the air that swirls in behind the truck. That air is part of the entire airflow around the vehicles, and drag is the result of the entire airflow.
The car is not actually improving the aerodynamic shape of the truck, which would then be an absolute gain for the truck as well. Tailgating is only an improvement for the car.
--Gaianne
But in tailgating, the car is being carried forward by the air that swirls in behind the truck.
The largest gain for the vehicle in the rear is the tremendous reduction in the velocity of the air relative to the velocity of the vehicle. Since aerodynamic drag is proportional to the velocity of the air, then it can take far less energy to remain 'tailgating' to the vehicle in front.
Mountains do have effects on the wind, but not what you might think. The best locations for wind farms are treeless areas in or near mountain passes, because the mountains on each side funnel the wind and create a "wind tunnel" effect that creates much higher wind velocities.
Mountains do indeed have a significant negative effect on wind, which is also why countries such as Switzerland have hardly any good wind sites apart from those rare places in the mountains with your "wind tunnel" effect such as this:
http://upload.wikimedia.org/wikipedia/commons/1/1e/Windfarm_Guetsch.JPG
By the way - this comparatively small wind tunnel built by men consumes 88 MW (lot's of friction in a wind tunnel even though it is a closed loop system): http://windtunnel.onera.fr/s1ma-continuous-flow-wind-tunnel-atmospheric-...
I was thinking of the wind farms near Crowsnest Pass in Southern Alberta, which is one the the best places in Canada for wind farms. The windiest places in Alberta are right next to the mountains - the Chinook winds coming off the mountains sometimes blow at hurricane force.
If they blow at hurricane force, the parks will generate nothing. They are designed to put the blades in flag position at wind speeds >80-90 km/h (50-55 mph)
I've read that the turbines they use in the Crowsnest Pass are capable of operating up to 78 mph. They have to shut them down if the speed goes over 78 mph, but occurs infrequently.
From what I've read, the whole thing is driven by a huge cyclone that forms around a low pressure system occurring off the Gulf of Alaska, and a low that forms east of the Rockies. These drive strong southwesterly winds that flow from the Pacific into Montana and Alberta. Crowsnest Pass is the low point in the mountain ranges there, and it funnels and accelerates the winds as they blow through the pass and out across the plains.
The pass is high enough that the normally high altitude winds reach surface level as they go through, and where they hit the ridge tops is where they put the wind turbines.
That's the explanation I've seen. Actually, that's the simplified version. The complicated version goes on and on for pages.
I wonder how much more power could be harvested if the maximum operating speed for turbines was increased by 5-10 mph?
NAOM
I doubt it would be all that much (infrequent events), and the cost of the bigger generators, stronger blades, towers, bearings, etc. would have to be paid out of that small increment.
The truck drivers hate it because they can feel their truck slow down
I suspect they're imagining things. I'd be very curious to hear a physics-based explanation for an effect like that.
I suspect it's the opposite. The bow pressure from a vehicle close behind ought to reduce the truck's base drag to some extent.
Exactly, it reduces the low pressure zone behind the vehicle which reduces the total aerodynamic drag of the vehicle.
Actually, I checked and it appears the truck drivers are imagining things. Drafting doesn't have any effect on the truck. However, they really do hate being drafted by people, anyway.
The advantages of drafting a truck were confirmed by Mythbusters and are quite dramatic - up to 39% if you are 10 feet behind them. However there is the real risk of rear-ending the truck if it stops suddenly. Unfortunately Mythbusters didn't measure the effect on the truck.
If you checked it out, you checked it out wrong. Drag on truck plus car together is greater than drag on truck alone.
True but less than the sum of the drag on each individually. The truck may help the car but the car also helps the truck. There are ideas for automated driving so that vehicles can drive in close convoys to take advantage of this..
NAOM
They already use it in automobile racing. NASCAR racers have discovered "bump drafting" in which the rear car takes advantage of its lower air resistance to put its bumper against the car in front and push it to go faster.
They discovered two cars using this technique, which they call "two car drafting", can be 15 mph faster than one car alone. Of course, they only do this with their team partners, and it's not really safe because it destabilizes the handling of the front car.
And following the same line of thought, to bring the truck back to its untailgated drag, the car would have to contact the tailgate and push it. If the car could do that, the truck would experience no loss, while the car, even after the loss due to pushing, would experience some gain.
--Gaianne
to bring the truck back to its untailgated drag
Tailgating doesn't create drag for the truck. If anything, it lessens the partial vacuum behind the truck, and helps the truck drive very, very slightly faster.
The truck helps pull the car. Energy loss for sure.
--Gaianne
No, it really doesn't.
Let me try an analogy: If I cut a path through the jungle with a machete, someone behind me will have an easier time, right? And yet, I'm not pulling them through, I'm just reducing their workload.
Or, if I plow a path through the snow, a car behind me will have a much easier time, but that doesn't mean I'm pulling them.
Or, if Moses parts the Red Sea, the Israelites can pass through, but Moses doesn't have them on a rope...
RockyMtnGuy
you can't get around the first law of thermodynamics. If you generate energy from wind, then you are taking energy out of the wind - over and above the energy that would be dissipated by friction with the ground.
If you extract energy from the wind in the lowest 200m, less will be dissipated by friction with the ground(ie the air mass is moving slower. The important point is that this doesnt persist very far down wind because energy is being replenished from higher altitude higher velocity wind. The greater the slow down by a wind farm the greater energy transfer from higher elevations and the lower the frictional losses from the ground.
"X" do you notice any reduction in the wind speed now that Iowa is getting approximately 20% of its electricity from wind power?
Yes, precisely. That's the whole basis for wind power. However, by increasing the effective "coefficient of friction" (or "characteristic roughness length") of the surface to wind passage, a wind farm reduces the average speed at which the wind needs to blow in order for dissipation to balance input. The point remains that the limit to how much power can be tapped globally is the rate of global input, not the measured distribution of wind speeds in the absence of windfarms.
I'm not saying that the study summarized above is correct, and that global wind power potential is really as limited as the study concludes. I'd have to study the full report carefully to be able to comment on that. What I am saying is that the methodologies that I've seen used elsewhere to estimate global wind resource potential have always struck me as flawed. They are fine for estimating the potential of individual sites in isolation, but don't account for the small but cumulative impact of each wind farm on its distant neighbors.
Clearly the kinetic wind energy above 200M is much greater than that below, perhaps a hundred times greater*. And this energy/momentum is being transported downwards by turbulence. So if you pick a characteristic time for the atmopshere to come into equilibrium, you need to consider the energy drawn from the entire system, not just the lowest 200M. It is quite possible, his calculated limit is one or two orders of magnitude too low, if he used the wrong methodology.
* A lot more air, halfway up, in terms of the number of molecules of gas, is roughly 18000feet (5plus KM). And higher windspeeds, jetstream like winds, often above a hundred miles per hour. So clearly the actual wind enegy in the boundary layer, is a tiny fraction of the total. So the question becomes, how quickly does the energy diffuse downwards.
I've always wondered as to the large-scale effects of wind farms.
If wind is Nature's way of equalizing pressure differentials, then slowing the average speed of the wind through wind farms must mean the differentials persist longer, which means the wind must increase over time, which seems wrong.
But imagine stirring your tea. The spoon is the solar driving force, the tea the turbulent atmosphere, and the inner surface of the cup the earth. If we roughen that inner surface (i.e. add wind farms) but stir with the same intensity, the tea not in the rough boundary layer will be agitated more.
By analogy, wind farms will make the winds more intense in areas (volumes?) with fewer obstructions.
Does this make sense?
I think its more complicated. I also don't think energy is a very good thing to use here. Momentum is conserved, but wind, and especially the transport of wind momemntun from higher altitudes towards the surface (which is really what we are talking about here), is dominated by turbulence. Turbulence turns large scale motions into smaller scale motions, then those into smaller still, until the energy is dissapeted as heat. So it is better to think of the thin boundary layer that we can build turbines in, as being supplied with momentum, from higher levels of the atmosphere (1 to 10 kilometers mainly). I doubt wind harvesting will have much effect on those higher levels, what matters is downwards transport of momemntum, versus frictional loses. Clearly near and immediately downwind of the WTs, the boundary layer has lost some momentum to WT induced friction, so those winds are slower. Firther downstream its hard to say. It could be that large scale eddies, created by the WT, might transport more momemntum down than would be the case without them. I think you'f have to due detailed simulations, or actual experiments to work it out. When you have miultiple effects that can cancel each other out, there is no susbtitute for mathematical analysis, rhetorical thinking just isn't a good way to tackle such issues.
Interesting approach. Doesn't feel right to me either, the world is a pretty big place. Even with 22 times as many wind farms, they'd still be pretty rare. But the numbers are clear... interesting.
I'd like to see a sensitivity analysis around the 200 m assumption. How does P0 vary with height? With an order magnitude uncertainty in the P 0 estimation (340 TW to 3600 TW) it seems important. What happens at 250 m, 300 m?
Wind mills or wind turbines?
I suspect there may be a flaw, He excludes all the areas we won't get wind from (deep seas etc.), then invokes using up the global resource. I would think the only way you take too much global wind, is if you take wind from all the areas of the world.
That said. I've always assumed that good wind sites would be used up pretty early on, and that this would limit the practical size of the resource. PV, actually has much greater potential than wind -and a faster growth rate. But, from a much smaller base.
Exactly my thinking. This must be the most obvious error in the piece. Betz law and the 30% interaction with blades also seems like double accounting, but I may be wrong.
Also, I agree with the folks that claim it just isn't a reasonable result. 22x is obviously too little.
I believe that current turbines already get close to 0.5 (Betz limit is 16/27), so an extra 30% is only reasonable as a factor for crosswind turbine spacing. I'll let you re-read with that in mind, I have no time ATM.
I always believed that the very optimistic projections were unrealistic.
However, you effectively push back because the analysis doesn't quite pass the smell test.
--There is no space in the argument for technical improvements in the technology. Recent experience would imply that improvements should be expected. More efficient turbines or more effective placement
--Why not put turbines either at sea or in Antarctica? Wind potential in the Aleutian Islands is tremendous. If we are going to suppose that we can deal with nuclear waste, then is it quite likely we can figure out how to effectively transport power over long distances.
Betz limit is 0,59, we use 0,5 as the rate of electricity being produced from the kinetic energy, far away of present technologies.
We use fields of class 3-6 although most present parks with present technologies are only in class 5 and 6.
We suposse than 75% of the kinetic energy move at maximum efficiency the mills but at present at high velocities mills do not work so well, even stop.
All other down-top assessments exclude deep sea an Antartica, we follow the published scientific literature. I doubt about the EROEI and the economic efficiencies of this remote places.
It is interesting than nobody apparently criticized down-top assessments less generous than our estimations when the results was about 100TW of primary technical limit...
Dave from Oregon said: Wind potential in the Aleutian Islands is tremendous.
It is indeed. I have a relative who worked up there (Dutch Harbor) for a few years. I was dismayed to learn from him that the local electric supply in the Aleutians is mainly from diesel fuel.
That was a couple of years ago. Since then a little progress has been made, but not so much given the huge wind resources they have. I found this article, which is recent:
http://findarticles.com/p/articles/mi_hb5261/is_8_27/ai_n57960638/
Sounds like they are doing more with hydro than wind.
As for sending power out on long-distance undersea cables, that would be nice but I'd expect a big transmission loss. The Aleutians are far from anywhere, even Anchorage.
I think you're missing a bigger story in Alaska. The Kodiak Electric Association has already shifted largely to hydro and wind, and is looking to upgrade the hydro plant and add more wind turbines to go 95% RE.
That's not what the report says, it does says 1 TW for economic resource. You know, as with peak oil: unlimited oil, but not unlimited cheap oil ;)
With 2, he rules out unproven geographical area deemed not enough economic, future will tell.
And with 4, he ruled out places with low potential, we regulary see capacity factor of 10-15%, I'm ashamed to see such waste. The global capacity factor is around 25%. If 25% is the threshold for economic wind power3, that's mean we got lot of uneconomic wind power. See China wind capacity factor1, or US states capacity factors2.
____________________________________________________________
1 http://en.wikipedia.org/wiki/Wind_power_by_country#Annual_wind_power_gen...
Germany had less then 19% in 2009
2 http://www.eia.gov/cneaf/electricity/epa/epa_sprdshts.html
Using
http://www.eia.gov/cneaf/electricity/epa/generation_state.xls
http://www.eia.gov/cneaf/electricity/epa/existing_capacity_state.xls
Iowa in 2008 had 17.5% capacity factor, still producing 10% of US output.
3 Offshore wind power have an higher capacity factor but since they have higher cost, it's not necessarily economic. Although everybody agree that 10% capacity factors is not economic.
First of all the wind turbines belong to private investors and they are only paid for the energy they actually produce. If they produce less they get paid less - its their loss not yours (as opposed to bankers who lose money with credit default swaps and collateralized debt obligations where the entire world economy has to pay dearly and this without even getting anything in return at all).
Besides even a wind turbine with a capacity factor of 19% will still produce power about 50% of the time.
The same is the case for PV systems with even lower capacity factors.
Moreover, there are wind power solutions for capacity-factor-philiacs:
1. Higher towers
2. Wind turbines with more swept area per kW.
The new Nordex N117 produces a 80% higher capacity factor than the popular Vestas V80 at the same location:
http://www.nordex-online.com/fileadmin/MEDIA/Gamma/Nordex_N117_2400_en.pdf
If I check in the paper, I can only see:
Your document seems to says 20%. I don't know what to think about the 20% more means 40% capacity factor, I can't see how 19% * 1.2 = 40% unless the 40% is theorical.
Now, I can assume the Nordex N117 dosen't cost that much more, so you get more power with a little more money.
What I care is actual output versus cost. I don't care if the turbine is up 50% of the time, or 1% of the time, it's the quantity produced that I'm first concerned about.
Cape wind is a bad exemple, but let's run the numbers:
Cost is $2.5 billion and annual production is about 1.5 billion kwh (using the wikipedia entry). That gives us a construction cost of $1.66 per kwh.
If you take nuclear, we have $14-18 billion for 17.3 billion kwh, hence around $0.90 per kwh for construction costs.
Nuclear reactors last 60+ years, wind farms 20+.
Operating cost for offshore wind farm are about 2 to 4 cents/kwh 1, nuclear is 2.2 cents/kwh 2
______________________________________________
1http://www.ecn.nl/docs/library/report/2007/m07120.pdf
2http://www.eia.gov/cneaf/electricity/epa/epat8p2.html
3,500 full-load hours at typical locations
3,500 / 8760 hours = 40%.
Clearly, "anyone"'s 80% increase comes from making a different comparison than the vendor literature.
Cape wind is a bad exemple
If that's the case, why use it?
You get to know how I rate a wind farm economic or not. I don't factor the intermitency, yet. I just check the cost versus production and check others thing separately.
Therefore, you need a construction cost below $0.90 per kwh, at least, to convince me of the economic viability of theses.
I hate using a cost based estimate of the actual cost of electricity (i.e. 6 cents per kwh). Because it does includes, lifetime, capacity factors (which are notoriously inaccurate and subject to speculation), interest rates and a whole bunch of other things that may or may not be included (subsidies, no subsidies, fuel (increasing price or not)). Therefore I just like to get a hold on actual production and actual construction cost.
The N117 has a 80% higher rotor_sweep/power ratio than the V80.
This corresponds to a 80% higher capacity ratio at the same location. Possibly even more because the N117 has a newer blade design too.
Keep in mind:
Wind farms also don't depend on uranium imports, aren't exposed to high pressures, high temperatures and high radiation and actually have lower operating costs, don't have high decommissioning costs, don't require ultimate repositories, don't need any cooling water, don't need tax-payer paid insurance and don't need taxpayer-paid organizations such as IAEA and Euratom.
... and they cannot be scheduled, do not have a generation profile which matches daily, weekly or seasonal demand, and are thus limited to some tens of percent of total generation without very large investments in storage systems not yet built on anything close to the required scale.
In March Spanish wind farms covered 21% of the electric demand:
http://www.windpowermonthly.com/news/1063600/Spanish-wind-record-month-M...
And Spain hasn't invested in storage systems and can easily replace some coal power with already existing combined cycle power and wind and thus significantly increase wind power without dealing with any new storage systems whatsoever:
https://demanda.ree.es/generacion_acumulada.html
And there's always more wind in the European winter and more PV in the European summer.
?!?!? Where is your source on that. I don't see ANY link between the rotor sweep/power ratio and the capacity factor.
117 and 80 stands for rotor diameter in SI units.
I certainly hope you know how to calculate the area of a circle based on the diameter and I gave you the nameplate capacity of both wind turbines. This is arithmetic for beginners.
You didn't answer my question.
Why is the surface of the turbine change the capacity factor of the turbine?
Oh, sorry, I didn't realize that you don't even know the basics regarding wind energy:
E = 1/2 m . v^2 = 1/2 (A . v . t . ρ) v^2
Same location means: v, t, ρ are the same and only A changes: A = d^2*pi/4
Example:
50% more d = 2.25 more produced E per year
capacity_factor = produced_E / (P*1_year)
You get to divide by P*1_year, which is, incidentally higher on the N117.
The smaller turbine is 2MW and the bigger is 2.5MW.
The bigger might produce more, but has bigger capacity too.
It's exactly like having more windmills, you get to have more surface, while more surface means more energy, it also mean the capacity is higher.
The only difference is in the height of theses, since the wind is stronger and more constant up there. (Or offshore, since the wind is more constant and stronger here too).
The V80 is rated 2 MW and the N117 is rated 2.4 MW which I took into account.
(double post)
Where you talking of capacity instead of capacity factor?
Amazing that nobody has done this calculation before.
If the wind generator is placed at 1000 meters, then f1 becomes about 0.4, and f4 probably becomes about 0.7. The resulting available wind power is then about 8 TW. This illustrates that some form of tethered flying wind generator is the way to go.
Vaclav Smil has done it, for one. In Energy in Nature and Society he says "Generous estimates of technically feasible maxima (economically acceptable rates may be much lower) are less than 10 TW for wind, ..."
At this level of detail, this estimate is essentially identical to Smil's.
Vaclav Smil has written some flawed stuff....
Could you point to any example? I've read Smil extensively, he was a bit reluctant to recognize peak oil and in general, predictions about energy.
> Vaclav Smil has written some flawed stuff....
Maybe. I had to overcome my incredulity a few times. But when I did investigate a few things, I came up with minor quibbles and uncertainties. Nothing that was clearly wrong.
... that is, leaving aside the typos. That book has at least two on every page. Someone sure cut costs on the sub-editing.
Yes, I think is the holistic approximation.
See Axel Kleidon contributions (Miller, L.M., et al., 2010. Estimating maximum global land surface wind power extractability and associated climatic consequences. Earth System Dynam. Discussion 1 (169–189), 2010. doi:10.5194/esdd-1–169-2010).
Just because there is more energy up there doesn't mean we can tap it. I'd stick with convential wind turbines.
Interesting, indeed.
What about high altitude wind, as in the kitegen project?
Details are here:
http://europe.theoildrum.com/node/5538
http://europe.theoildrum.com/node/5554
Airborne wind energy is alive and progressing. But we are starting small and it takes time. We are edging towards commercial energy production systems, but we are not there yet. Once that stage is reached, the potential is immense.
See before. This technology has a very little f3. The extractable electric power will be much less than 1 TW.
You should clarify that in this global top down approach you seem to be working a basis of continual production. Thus since wind farms have an average load factor of roughly 25% your 1 TW would equate to to roughly 4 TW of installed capacity generating 1 TW on average on a global basis at any one time.
Other than that I think it's a very interesting contribution. Just to make an appallingly unscientific connection I wonder if it might have anything to do with the UK's recent record low winds.
Also I don't think 1 TW is too bad, if it equates to 8,760 TWh. I'm not sure what the world's total electricity consumption is but UK is a bit less than 300 TWh pa, so it's quite a few multiples of that. I never thought wind could produce more than 20 or 30 % of total anyway, realistically.
Now for your next trick, work out what the impact on climate and global wind resource will be from thousands of square kilometres of solar absorption for energy from land that would previously have been highly reflective (i.e desert).
Global electricity consumption is about 17,000 Twh.
Thanks, I was on my IPhone yesterday so couldn't look it up. In that case, the realistic potential for wind power is less than 1TW of average power output anyway, so it doesn't really matter.
That means if the 1 TW estimate is correct, 52% of world electric energy could be provided by wind (1TW*24h*365days= 8760TWh/17,000 TWh. Not too bad. If every factor that went into this estimate is only a little bit too low, then all of today's world electricity could by supplied by wind, if the power can be stored or transported over long distances.
And/or if smart grid technologies are employed within the blend of storage and transportation.
http://www.rltec.com/gridbalancing
1TW*24h*365days
Wait a minute here, it's wind power and wind power is intermittent. Using economic resources, we'll use a capacity factor of 40%, so we'll have 3504 TWh.
Wrong.
1 TW refers to constant average power output in this particular study.
So yearly production would be 8760 TWh.
Yeah, I just read the rest of the discussion and was about to remove the post. Dang, you were too fast. ;)
Thats actually fairly easy. The ratio of total solar input to human energy consumption is several thousand, so at efficiencies of roughly 15%, we need to intercept about .1% of the total solar energy incident on the surface. Our greenhouse gas climate perturbation is already on the order of one percent, so this is an order of magintude less. And that assumes all the intercepted solar would have been reflected into space. Most would have been absorbed on the ground, or not get back through the atmosphere into space. Of course if we do the old exponential growth thing, in under two hundred years you need the entire energy falling on the planet.
I think your math is wrong. Radiative forcing is around 1 W per square meter. This is much less than 1% of the incoming solar radiation. Actually, 0.1% is about was is captured by photosynthesis, which gave a good idea of the impact of such large scale energy capture.
The earth radiation budget is something like 240 watt/meter squared. I think current CO2 is 1.6. The solar constant is roughly 1350. Divide by four for geometry, then take out about 30% due to reflected energy.
Thanks, but it was more local and wind effects that I was interested in. As far as I know the major cause of wind is differential heating of air, (with that flow then influenced by the rotation of the earth via the Coriolis force) so if there is a big change in absorption/reflection properties over very large areas, will it have an impact on the driving force of the wind? At the very least I would think that a solar plant would carry on heating the air around it all night long, if that plant were big enough surely that would have a climatic impact if not globally then at least locally in terms of overnight atmospheric pressure?
A PV panel can cool very quickly. What hits urban areas nighttime temps, are surfaces that are connected to large thermal sinks, that absorb heat during the day. Pavement, seems to have a pretty long thermal memory (taking several hours to heat/cool), whereas stuff like vegetaion or unpacked soil, changes its surface temp within minutes. I can recall being in the Phoenix area during a summer heatwave. If you stepped onto a sidewalk barefoot, at midnight, it was still hot enough to burn your feet!
But again, PV & solar thermal, needs a pretty small collection area. Also most vegetation has pretty low albedo anyway, and outside of deserts and snow/ice covered unvegetated areas, the surface albedo is actually pretty low, so putting up dark panels only affects the shortwave energy balance by a little bit.
FWIW, someone on GCC worked out the temperature difference caused by albedo shift due to solar power build out. It worked out to something like 0.01C. It might have very well been Engineer-Poet who did the calc.
I would have been proud to have done such a calculation but I do not recall ever having done so. Then again, I've forgotten a lot.
This doesn't bode well if we need to get from 17 TW for 7 bn people to say 22 TW for 9 bn. Another issue is that of factors that are unlikely to be repeated. The 25% annual growth in windpower can be attributed to a mix of economic incentives like subsidies (feed-in tariffs, capital grants, green certificates) and mandates (percentage quotas, targets, must-take requirements) which may not be affordable in years to come.
I wonder also whether it might pay to replace existing turbines on prime sites with more efficient models rather than build on new but inferior sites. I think it means future wind power is likely to show declining net energy per capacity installed. That is, despite design improvements a new megawatt of installed wind power may deliver less net energy to the final user than was historically the case. This is due to inferior sites, wind shadowing and extra transmission. The net energy optimum may be well under 1 TW installed.
"I wonder also whether it might pay to replace existing turbines on prime sites with more efficient models rather than build on new but inferior sites."
That's going to happen anyway. Windmills have moving parts that will wear out. Eventually replacement will give a better NPV than repair.
When it happens that will bring up a good question for the accountants to sort out. Do you replace the nacelle with something about the same size but presumably more efficient, or do you cut down the tower, blast the foundation, and start completely over? The answer will probably be very site specific.
Perhaps you can add new nacelles with wind lenses.
http://en.wikipedia.org/wiki/Wind_lens
My daily commute has extra delays now, because of just that. Old junky first gen turbines are being torn down, and big modern ones erected.
I'm guessing you drive Altamont.
Those turbines are 30 years old and short. They are being replaced by fewer, but taller models. Stuff we didn't know how to build three decades ago.
There were several test turbines up there. It served as a useful nursery to get the industry sorted out. Some of the designs were real turkeys.
Probably in 30 more years we'll look at the current set as a bit primitive. But they, like their predecessors, will have cranked out a lot of useful electricity.
We've got some new blade technology in the works that will change things.
I'm not sure if Vasco road counts as Altamont, although its the same hills a few miles further north.
I doubt the EROEI from those firt gen systems was very good. They were invaluable for building up the industry, but the delivered power wasn't much. Thats usually the case with brand new technologies, the first gen isn't cost effective, and only if someone has enough vision and will to commit the resources to do it anyway even though the direct payoff is lousy or negative, does the industry have a chance to be born.
how old were they?
This is a very interesting way to estimate the potential of wind power. However I believe it merits a much more detailed study.
The reason I believe this, is that the first two factors, f1, f2 do not include dissipation of energy. In the case of f1 some energy from the higher layers of the atmosphere will dissipate into the lowest layer. The same argument applies for f2, energy will dissipate from unsuitable to suitable areas, that is wind will blow over deep sea and eventually reach the coast. If I now assume (unrealistically high) values of f1=f2=1, then the total extractable energy would be 67 TW, more than enough for global primary energy consumption.
Therefore the estimate could be relaxed such that wind would be a viable alternative for global energy production, but indicates that large scale wind power could alter wind patterns. And both questions, if wind energy is viable and whether wind patterns will remain stable are rather interesting.
See before. Some energy form the higher layers will dissipate into the lowest layer and some energy will dissipate from unsuitable to suitable areas. But also the reverse, and, as far as the models presently show the reverse effect will be greater, I think we are optimistic with the assumption of no interchange. But yes, "it merits a much more detailed study".
Sure Mankind uses a large amount of electricity but compared to renewable's such as wind,solar,wave etc our consumption is negligible.Any one of the major renewable's alone could easily power our needs 100 times over.Only those that have a vested interest in seeing renewable's fail will speak,talk,write,persuade etc against em.Sure we need to advance the renewable technologies further to be able to harness much more of the renewable's using less.
We need to group and take on our wordly problems once and for all.
I have similar estimate at 15 TW for wind power and something like 80 TW for the whole renewable energy available trough the biosphere. As many other I do some calculation and came to the conclusion that even pure renewable energy filling all own need in 2100 is unsustainable if energy consumption is growing at 2% rate. Indeed, energy withdrawal from the atmosphere will exceed the actual impact of the CO2 radiative forcing.
http://www.scientificamerican.com/article.cfm?id=a-path-to-sustainable-e...
Our author has his point of view, but I think there is plenty of room to do more than his calcualtions come out to.
Hum, 50 km2 is 50 millions m2 divide by 3,8 millions you get 17 m2 per windmill. This is off by at least 2-3 order of magnitude.
And then economics intrude.
Solar is not really rational outside of the arid tropics and sub-tropics - the descending-air parts of the Hadley cells. Further away from or closer to the equator, the light intensity and load factors get too bad. A solar power plant that operates for three months of the year is not a good use of resources. 580 TW looks a little high.
With wind, you need steady winds at 8 to 25 m/s. (Steady in direction and in speed.) It turns out that a lot of the world has gusty, variable wind, daily and seasonally. And in some places the wind sometimes rises to destructive speeds. A wind turbine that operates for one day per year, or even two months per year, is not a good use of resources. Nor is one that has to be rebuilt or re-tethered to its ocean bed mooring every two years.
Yes, we could do lots, if we had unlimited money and nothing better to do with it. Neither is likely.
OT: Where is Jerome a Paris these days? Anyone know?
Well, we have fiat currency and think buying trinkets and bottled water is a good use of it.
Just sayin ;p
It seems to me that wind turbines extracting energy from the lower atmosphere and slowing the surface wind speed would increase the rate of energy transfer from the winds above.
Do these estimates take into account wind blowing into a mountain from a lower plain which extracts energy from wind that used to be above 200 m? The Earth is not a perfect sphere.
It seems to me that more wind energy is dissipated over land than over ocean because the ocean is flatter. The ocean winds will blow into areas where wind turbines are located before being mostly dissipated. I suspect you have chosen f2 too low.
If this guy was right we would have stopped the Earth's winds with the multi-story buildings we've erected.
That's an off-the-top-of-my-head calculation. But think about it. Are we likely to install more tower/blade surface than we've installed in building walls? Is the wind still blowing?
This is probably like the bogus land use data anti-wind people use. Where they use the total size of the wind farm and not the ~2% taken up by footings and access and then talk about how we would put ourselves out of food production if we build enough wind capacity. Set up a false argument to support your bias.
I'd treat this study very carefully until it was vetted by someone expert in the field.
It doesn't necessarily take expertise in the field, just careful examination of the figures and the assumptions behind them.
There is a recent "study" about the potential of vertical-axis wind turbines which claims they are several times as efficient as HAWT's. I dug into the paper, and found that the authors were measuring power output divided by the ground footprint covered by the turbine's circle of rotation, and not the output per unit of area exposed to the wind (a HAWT rotates so that its footprint is its entire rotor disc, while a VAWT's vertical extent does not affect its footprint). When properly figured as output per unit of cross-section exposed to the wind, VAWTs are only a fraction as efficient as HAWTs even by the figures of the authors.
I claim no expertise in the field, just the desire to pursue truth, root out error and do the required arithmetic. Anyone with a reasonable IQ should be able to do the necessary calculations and unit analysis... it's just a question of who will.
Aren't the winds earth's solar energy running downhill? Are the windmills going to somehow stop this progression?
*listens to the rustling in the trees*
*edit*
sorry, long day at work, and took 4 hours to read while I was doing other things. Think I agree with x's points above though. Just had forgotten that I'd read them by the time I stated them.
Also, isn't there a perpetual mover to the winds from the fact that we're on a spinning planet? Think of swirling toilets.
Did y'all factor in that we're on a sphere and alot of these forces tend to cancel out All The Time?
If this guy was right we would have stopped the Earth's winds with the multi-story buildings we've erected.
Wouldn't have all mountain ranges and forests stop Earth's winds in the first place?
Are we likely to install more tower/blade surface than there is mountain range and forest area?
And mountain ranges, don't just create local friction, they create atmospheric waves that can go on hundreds of miles downstream. And these are a major source of frictional dissaption within the atmosphere. I doubt anything we could do to the lower boundary layer could come close.
I cannot comment on off-the-top-of-my-head calculations.
Frictions of glass or brick buildings with frictions of rotating blades. We know very well how much they capture/intercept, transform, out of the exiting total energy in a given wind flow.
Can you give us some hints, apart from you off-the-top-of-my-head calculations about frictions of winds with a building of a given material shape and height? Can yuo extrapolate to all cities in the world, including the slumdogs suburbs of Calcuta?
There are some things in this busy life that we simply have to evaluate on a Heuristic level, and just decide whether it's worth going out to the next stage and doing the research and the math..
I would be fascinated to hear what someone comes up with, when adding up all the;
industrial towers,
skyscrapers,
telephone poles,
High-tension Line Towers,
Ski Lifts,
Oil-Rigs,
Container Ships,
Very Large Crude Carriers,
Railway and Highway Bridges,
Dams,
Great Walls,
and other Manmade Wind-barriers..
(to name a few things..) as well as perhaps deducting a bit for all the Deforestation, Desertification and Mountaintop removals that we've also had a heavy hand in.. but I'm really hard-pressed to believe that the question of windfarms affecting Global Wind to a worrying degree is really very high on the list of Global Concerns, or how much, in fact it would really affect wind patterns and force to such a degree that it would impose a limit on the amount of energy extractable from wind currents.
As mentioned above by BOTH sides of this argument, the vastness of the oceans might be visited by 'some' wind production, but will really barely be touched by this intrusion.. so I'm left to wonder how serious our impact really can be to the global air-currents.
Yes, we've said such things before, about the Whales, about Petroleum, about the Fishing-Grounds.. 'they're too big for us wee humans to EVER affect" and yet we've truly been able to mess up our Biota, and we continue to do so. But the inclination to give renewables an extra set of hurdles to pass seems to be an almost irresistable snack for the eager iconoclasts.
If only as much energy were being put into challenging Coal.. ... maybe that's just too easy?
Yair...I'm missing something here. How is the flow of air any different to the flow of water? I can't find the link but I recall a picture of dozens of "mill boats" secured along a river bank all extracting energy from the flow.
Could someone explain?
Cheers
These two terms are not independant. If one wind farm does not capture all the energy from the high speed wind, then there is some energy remaining for the next wind farm to capture. Basically the wind farms will capture all of the kinetic energy until the wind speed drops below the minimum wind speed needed to generate power. f3 should be 1. With many installed wind turbines, there will be little wind that exceeds the maximum wind speed. Maybe f5 should be a little higher, maybe not.
Yes, it is discussed in the original paper, there are a trade balance among some of the f factors. For instance also beetween f3 and f4.
But the important think is not that f3 is 0,33 or 0,27. We think we do the estimations very generously, for instance f2 < 0,2 is very generous if you think than deep seas and Antártida and other ice covered sites are excluded; we follow Archer, C.L., Jacobson, M.Z., 2005 (Evaluation of global wind power. Journal of Geophysical Research 110, D12110. doi:10.1029/2004JD005462). Probably f2 is around 0,1 but an specific study will be needed.
f2 represents the geographical restriction. Wind is mobile, and I am not sure if its lifetime is localized or global. What fraction of the wind power in the lower 200 m of the atmosphere is dissipated over ocean and what fraction is dissipated over land? The ratio may not be the same as the geological ratio, 75% water and 25% land. I suspect there is proportionately more wind power dissipated over land than water. If so, it means some of the wind power over the ocean is available over the land making the value of f2 = .2 too low. Miller, et al., made the same assumption in his back-of-the-envelope estimate.
Estimating Maximum Global land surface wind power extractability and Associated Climatic Consequences, L. M. Miller, F. Gans1, and A. Kleidon, Sept. 15, 2010, Earth Syst. Dynam. Discuss., 1, 169–189, 2010 (PDF warning, 11.7 MB)
The energy transfered to ocean waves are around 60TW, therefore in the first 200m more than 60TW dissipate over the oceans, more than the 60%, may be more than 75% and may be less. You have Antartica (the windiest continent), it occupies less than 3% but dissipate more than 3%. And do you have many other inaccesible (technical and economical) sites: Amazonas, cities, Himalaya... Really 20% of Earth is accessible? it seams too high.
In our paper:
"...referred to in Table 1, and is only comparable to the estimation by Smil (2008) ( <10 TW), except for the physical–geographical potential estimated by Miller et al. (2010), also using a
top–down methodology, which is 17–38 TW (our physical–geographical potential, applying only f1, f2 and f6, which is comparable to Miller et al. (2010)’s methodology and calculations, would be <40 TW). This means that technological wind power potential imposes an important limit on the effective electric
wind power that could be developed, against the common thinking of no technological constraints by economic, ecological or other assessments".
Miller et al. +f3+f4+f5 that they do not take into account will give 0,5-1TWe, even less than our limit.
Miller et al. paper reinforce our results not the contrary.
Basically your wind circulation model assumes wind is local. It is generated locally and dissipated locally with no transfer of kinetic energy from distant places along the surface nor from higher altitudes to the area within 200 m of the surface. This seem too simplistic to me. For example, a jet stream circles an entire hemisphere, and thunderstorms create large horizontal winds at the surface with a central updraft that can exceed 20,000 m.
If 60% to 75% of the total global surface wind is dissipated over the ocean, then there are large error bars that range from wind generated over ocean transferring net energy to land, to wind generated over land transferring net energy to ocean.
You can not arbitrarily group cities into f2 because some of them are also covered by f4. Be careful to avoid double counting.
Ocean covers 71% of Earth's surface (NOAA: Ocean)
You subtract some unknown amount for the area of the sea that has a depth of less than 200 m.
You add 3% for Antarctica (actual glaciated fraction is 2.7%).
You add some unknown amount for the ice sheet in Greenland.
You add a vague estimate for areas that are inaccessible on land due to technical, economic and political reasons arriving at 80% so f2 = .2. Combining that with f4=.5, you are stating that 10% of Earth's surface is suitable for placing wind turbines. I am not sure this is reasonable or not.
This article was useful - it is wrong enough that, after a long time reading this website without a user account, I finally bothered to create an account to reply to it.
The very first value used has an order of magnitude uncertainty, anything from a few hundred to a few thousand TW. From there, an average amount of wind power in the atmospheric boundary layer (200m or so) across the whole world is found, and it's a rough estimate of 100 TW. Seems suspiciously low to me, but let's carry on. Now since our planet has 510 million sq km of area, let's just call it 500 million, that comes to 0.2 Watts per square meter.
And from there, only the proportion 0.2 reachable land area and 0.5 of that area with "reasonable wind potential" is going to be used. But hang on a second, we are still going to stick with that average 0.2 Watts per square meter? Even though we are now only talking about the best, windiest half of reachable land areas?
From there, additional factors reduce it another order of magnitude: the area of wind on the turbine blades (f3 = 0.3), the proportion of wind speeds for electricity generation (f5 = 0.75) and Betz limit (f6 = 0.5) so we end up with only 0.02 Watts per square meter?
Like I said, hang on a second. Let's take a look at the real world. Right now in many countries there are wind farms that, even ALREADY accounting for all those other factors in the article calculation (the Betz limit, good wind site, conversion to electricity, etc) are producing around 6 Watts electric per square meter when the wind is between 15 and 25 m/s, and over all conditions at around a 1/3 capacity factor, average around 2 Watts per square meter. Sure, those are good wind sites, but this is a factor of 100 better than the article calculations.
It just doesn't add up.
Welcome to the fray, retro. Thanks for the clear analysis. This article seems to be a real stinker.
Hope to hear from you often.
With that remark, you both proved yourself the bane of doomers everywhere and gave me a very pleasant chuckle.
Welcome.
Please read the paper: the authors use the specific wind potential of the different areas in the Earth. In fact, they take areas of classes 3 to 6; classes 1 and 2 are considered not economical due to the low winds.
Your claim about what nowadays is being produced by wind farms is irrelevant in the context of this paper, as the main issue raised by the authors is that wind sites are not independent. In few words, they say that when you try to squeeze wind too much you will observe that the output of wind farms will decline, because the total power available is the same. What can be discussed is 1) if total energy content of lower atmosphere (up to 100 m) is really 100 Tw of equivalent average power; 2) if the proposed locations for wind mills really take the maximum profit from wind (taking into account economic factors as the authors do); and 3) if upper atmosphere would pump additional power into lower atmosphere when the last has additional dissipation.
Notice also that we are not talking of a post in TOD, but of a paper published in a scientific journal. Two or more referees, scientists, have reviewed the paper and undoubtedly they will have pointed out all the obvious deficiencies in the article; in fact, the final version is likely a polished, edited version after addressing the possible criticisms. Don't run into the easy, seemingly obvious criticism, and first read the paper.
Regards.
The article is pretty clear what the formula is:
1200 TW x 0.083 x 0.2 x 0.3 x 0.5 x 0.75 x 0.5 = approx 1 TW
In terms of area, the two area-limiting factors in their formula refer to 10% of the planet surface area (the 0.2 reduces to reachable land, and the first 0.5 reduces that to the better half, class 3 or better) so that is 0.02 Watts per square meter as I noted.
But that 1200 TW is a global average, and it is used even though the other factors limit the surface area being considered to significantly better than average land. It is applying a population-wide average to a skewed subset of the population, with the population being surface area of the Earth and the subset being reachable land area good for wind.
To draw an analogy, this is statistically comparable to saying "most people are between 4 and 7 feet tall, so we'll choose an average of 5 foot 6, and use that as a base assumption of height in our study of ... college basketball players."
Let's compare the article to some real world examples.
First, a large offshore wind farm: these tend to have a fairly dense paking of turbines, so they should demonstrate limits of performance for downwind turbines.
Horns Rev 2 has 209 MW electric nameplate capacity in 33 square km, and a 47% capacity factor last year - math works out to around 3 Watts per square meter of land. That is 150 times the maximum limit the article claimed.
Next, consider an entire country: Denmark consists pretty much entirely of that class 3 or higher land, and is easily the most "turbine saturated" country. But it also fairly lacking in really good onshore wind strengths, it has lots of land with fewer than maximum saturation of turbines (many are clustered along the western coast, leaving many areas out east to build more onshore eventually, after the current offshore focus) and it has thousands of older, smaller, less efficient turbines: the mean nameplate capacity is still under 800 kW there. So with that room to grow (by building more onshore, and replacing older smaller ones for larger models) you would think Denmark should have an onshore wind power harvest much smaller than the article's computed limit, right?
Well, Denmark is getting up to around 6 or more TWh annual generation from its onshore turbines, on 43,000 square kilometres of land, making an average of ... nearly 0.02 Watts per square meter. So even with a fairly modest onshore wind potential, and lots of older smaller turbines on land where newer turbines would get more energy per area, and room to add more capacity, Denmark is practically already busting through the supposed maximum limit.
This is an "Our calculations estimate that bumblebees cannot fly" article. One only has to walk outside and watch the bumblebees flying, or rotors turning in this case, to know the authors are wrong.
No, your analogy is silly. When we take a factor like f2 we do not refer to the surface available for wind parks but the power being dissipated in those available sites. And so on. In fact you take an erroneous and invented average (0,02W/m2) with no sense. The winds in Antartica will dissipate there know and in the future, we think that this power is not accesible, therefore we disccount it. Easy.
retrograde: "First, a large offshore wind farm: these tend to have a fairly dense paking of turbines, so they should demonstrate limits of performance for downwind turbines". Please read the paper and some of the literature cited. (See for instance Christiansen, M.B., Hasager, C.B., 2005. Wake effects of large offshore wind farms identified from satellite SAR. Remote Sensing of Environment 98 (2–3),
251–268 15 October 2005). They identify a loss of 10% of velocity downwind of the parks during around 10 km, this means that if you put a park there (as bottom-up methodologies do) you will have a much lesser efficient parks. Top-down methodology try to overcome this error.
Take another look.
You claim 1200 TW x 0.083 = 100 TW as rate of kinetic energy in the ABL across the total Earth surface. Then you multiply that by 0.2 x 0.5, your two factors that restrict the surface area being considered, to get power being dissipated at the 10% of the Earth surface that is the class 3 or higher reachable land.
But this is entirely invalid because the 10% of surface area you've selected is precisely chosen because it is the land having the best winds, the most ABL kinetic power available, other than the likes of Antarctica. (Yes, I know it's windy there - that would explain the three 330kW turbines at McMurdo/Scott bases.) Now if we take your final 1 TWe, and find power per area of that 0.2 x 0.5 of the world surface you are considering, we reach 0.02 W/m2. That is not an "erroneous and invented average" - the surface area of Earth is what it is and your 0.2 and 0.5 area-limiting factors are what you have chosen. I am not inventing an imaginary size of our planet.
You may not have announced that rate of power per surface area 0.02 W/m2 anywhere, but it is clearly the amount you reach because the surface area of the planet is well known and those are the two area-restricting factors in your formula. And looking at real-world large wind farms (getting 3 W/m2), and real-world countries that have built wind turbines (Denmark getting 0.02 W/m2 onshore with lots of potential to greatly increase that), like I did, we see your limit cannot possibly be valid.
P.S. It is interesting you cite Christiansen and Hasager. They indeed show 10% reduction in wind speed immediately after a large wind farm, and in some (note some) cases another 10% peak around 10km downwind, but citing only this finding of their study seems odd. I disagree that up to 10% constitutes "much lesser efficient wind farms" and you did not mention their overall finding: "wind speed recovers to within 2% of the free stream velocity over a distance of 5 – 20 km".
Wind farms have a power surface of about 2-3 W/m2, true. But Denmark reach a power surface of 0.02 W/m2. That figure can be send upward but you still need a growth of 100 fold to reach your 2 W/m2 figure.
I can see the gap between 0.2 W/m2 and the actual value of wind farms 2 W/m2. However, that value seems to goes down when the scale is bigger, i.e. Denmark value 0.02 W/m2.
If the 100 TW value is the right one and is likely te stay the same, wind farms power by surface can only go down as more get built.
You keep referring to "f1", "f2", etc. without any notation of what they represent. I think you would have an easier time convincing people if you worked to make things clearer and easier to understand; saying "f3" and forcing readers to jump elsewhere to see what it means does not help.
No. The 1200 TW is the total, not an average.
Yes I meant to refer to 1200 TW as a total, and from that the authors multiply by 0.083 to get 100 TW in the ABL, also a total. Then they multiply by 0.2 for reachable land and 0.5 for the best half of that reachable land, considering only 10% of the Earth surface area where wind farms may be built. But that 10% is not chosen at random.
If I found a population of 100 people and added up all their heights, then chose a subset of 10 people not at random but matching certain criteria, who largely because of that criteria happened to be among the taller members of the group, I do not expect the total height of the 100 multiplied by 0.1 would be a reasonable estimate for the total height of my selected group.
No. 0,2 is not the reachable land and 0,5 is not the best half of the reachable land. 0,2 is the kinetic power dissipated in the reachable land and 0,5 is the kinetic power of the best half of the reachable land (the best land is much lesser than 0,5 -most places are of class 1 and 2 by far- but because have more power per area then the best half of the reachable land has 50% of the power).
Wouldn't wind farms in the reachable land increase the proportion of kinetic power dissipated in the reachable land and reduce the proportion in unreachable land? I.e, wouldn't wind farms steal energy from unreachable areas as well as from reachable areas?
To draw an analogy, this is statistically comparable to saying "most people are between 4 and 7 feet tall, so we'll choose an average of 5 foot 6, and use that as a base assumption of height in our study of ... college basketball players.
Retrograde puts it clearly, I was having trouble formulating it, thinking - Oh that way you could prove Mensa members ...are stupid! (average IQ = 100 by definition - Mensa members are selected on their stellar IQ...) but then there’s the real world where Mensa members can obviously be shown up as dopes.
So it is a measurement problem, or better: the *disjunct* between logic and quantitative manipulations (math) performed on some measure (or quantity, or proposition) defined in a particular way (the arbitrary and very wonky IQ is a good example) and real world facts / examples becoming muddled, in their perception by participants, till the both the forest and the trees disappear from sight. (oh right, they cut down wind..;)
The tension between the two is a genuine, worthwhile struggle. Having it polluted by pre-set ideological stances or inflexible opinions (e.g. against wind, pro or anti nuclear, etc.) or even some rather indirect political slant is inevitable I suppose. (?)
An interesting article though, and some good discussion, it prompted me to post again.
Noirette - then Noizette.
Energy Policy? A scientific journal? hmmm
> It just doesn't add up.
Arguments from incredulity aren't ... well, they just aren't.
Arguments by analogy are pretty bad too, but consider how we've exploited every other resource. We've picked the richest, most accessible concentrations first. Extrapolating from current production is a good way to go very badly wrong.
Notice that this post is just a summary of the paper; if you are interested in the details you should rather download the paper instead of ranting here. For instance, about the assumed 1200 Tw power content of the atmosphere, the paper states the following:
"According to several authors, the kinetic energy that wind contains and is dissipated
into other forms of energy varies between 340 and more than 1200 TW (e.g.
Gustavson (1979), 3600TW, Lu et. al., (2009) 340TW, Lorenz (1967) 1270TW,
Wang and Prinn (2010) 860TW, Peixoto and Oort (1992) 768TW, Skinner (1986)
350TW, Sorensen (1979 y 2004) 1200TW, Keith et al. (2004) 522TW). These data
are obtained using global thermodynamic models of the solar irradiation on Earth.
Some consider the entire atmosphere, while others restrict it to altitudes lower than
1000m.
In our study, we will take the one of Sorensen, (2004), P0 = 1200TW, because it is
for the entire atmosphere and also gives turnover times of kinetic energy."
which is, of course, questionable but not unfounded.
The other line of discussions, about if the upper atmosphere would pump in additional energy into the lower atmosphere, this is in fact very unlikely because several reasons. Except at convection places due to thermal fronts and precipitation, atmosphere tends to be stratified. The final tens of meters of atmosphere, the ones closest to land, form the so-called boundary layer, in which the strong winds above adapt to the zero-wind condition at surface; the depth of this boundary layer depends on the drag (including turbulent drag) of the surface, among other factors. As a matter of fact, what typically happens at the end is that the flow adapts to circumvent places with high drag, passing by the sides or above; this is what happens, for instance, in the forest (notice that if drag is very high, at the end the situation is like the place was solid rock for what it matters to wind). So what we need is to create wind fields sparse enough to avoid diverting the wind flow upwards. In that sense, Carlos de Castro et al.'s approximation makes sense; they consider that what is presently being dissipated in lower atmosphere is about constant, what can be an acceptable approximation if the energy dissipated in wind fields is small compared to the total energy content of this layer (and that's the case, 1 Tw in front of 100 Tw of equivalent average power).
This work should be taken as a first approximation to the problem, not the final and right answer. Doing things properly would imply taking a detailed general circulation numerical model of the atmosphere, including the additional drag of the wind fields and then observing how general circulation is changed depending on the configurations and extents of these wind fields. After understanding all that, an optimization strategy looking for the best possible configuration should be searched, and from that we will obtain both which is the best configuration for wind fields and the maximum energy to be extracted from wind. As you can easily understand, this is a whole research program, and even an urgent one, I would say. The reason for which this article is so important is because it has introduced a different point of view about wind potential beyond the naivest one, which is to take the wind potential of all sites on Earth as independent: that is the very lowest order approximation, which makes only sense if the energy extracted is several orders of magnitude smaller than the total available energy, what is false. Unfortunately, that is the only point of view considered so far in all previous studies. De Castro and co-workers make a step beyond, and we should continue along that way.
Regards.
"This work should be taken as a first approximation to the problem, not the final and right answer". YES!
And also, we show that the down-top approach is not correct (they violate the first principle). Our conclusion is than during more than two decades we do estimations with a bad scientific methodology. The technical estimations are the basis for economical and ecological estimations, from international energy agencies to Greenpeace or WWF. Our political purpose is not diminish this technologies (I personally like it) but to catch attention than we are doing political decissions in flawed grounds.
"This is a whole research program, and even an urgent one". I think also, because the limits are not far away.
we show that the down-top approach is not correct (they violate the first principle).
Actually, I haven't seen anything substantive that supports this statement. Most of what is presented resembles vague generalizations without regard to site advantages, careful examination of mixing of wind currents from the 200+ meter layers, and advancements in deep water approaches.
If there is something more substantive that you have not presented, please share it with us so that we can have at least some level of confidence in your claims.
Did you read the paper?
See also:
· Gans, F., et al., 2010. The problem of the second wind turbine—a note on a common but flawed wind power estimation method. Earth System Dynamics Discussion 1, 103–114. doi:10.5194/esdd-1-103-2010
· Wang, C., Prinn, R.G., 2010. Potential climatic impacts and reliability of very large-
scale wind farms. Atmospheric Chemistry and Physics 10, 2053–2061.
Authors that use bottom-up methodologies conclude that the potential (with mills of 100m) is around 100TW, they exclude deep-seas, Antartica etc., they exclude sites with very low wind velocities, etc. They exclude also high altitude winds. How is it possible that we can interact and dissipate almost the 10% of all the power of all the atmosphere (10 km high)? If we do the reverse calculations of the bottom-up methodologies we could conclude than much more than 5000TW is the power being dissipated in the atmosphere. This is because this methodology do not conserve energy. We can not extrapolate to the global escale the velocities in local sites as bottom-up methodologies do. In fact, some authors, especulating about high altitudes winds, conclude than 1500 TW is dissipated only in the jeat streams, more than in the entire atmosphere!
The molecule that carry a good velocity in New York is the same than carry a good velocity in Tokio some hours later. If we take this two velocities and sum the power, we do the bottom-up approach, but if you catch this molecule in New York with a windmill, then obviously you will not catch it in Tokio (energy must be conserved).
I have not read the paper, I have commented on what is presented here. If there is more to present, please present it. Since your paper is behind a paywall, it is for all extents and purposes unavailable to the average reader here.
Authors that use bottom-up methodologies conclude that the potential (with mills of 100m) is around 100TW...How is it possible that we can interact and dissipate almost the 10% of all the power of all the atmosphere (10 km high)?
First, you need to identify which authors you are referring to. Do they all refer to 100TW as the harvestable amount of window power?
Second, you need to identify why you chose 1200TW as the maximum wind energy value. Do the other authors you mention above agree with your choice of values?
The molecule that carry a good velocity in New York is the same than carry a good velocity in Tokio some hours later. If we take this two velocities and sum the power, we do the bottom-up approach, but if you catch this molecule in New York with a windmill, then obviously you will not catch it in Tokio (energy must be conserved).
I actually agree with this, though have not seen a convincing explanation from you on how you modeled mixing of wind energy from layers above the layer you examined (or will you refer to a specific modeling effort that directly supports your assertions on this matter? If so, please refer to the specific values from said citations). You also note that f3 describes the amount of wind energy that does not interact with the wind turbines, so the unharvested wind energy is still available for capture in Tokyo, as reinforced by layers above the 200m layer you focus on.
"First, you need to identify which authors you are referring to. Do they all refer to 100TW as the harvestable amount of window power?"
I do not NEED to identify which authors I am referring. I expect that people believe me in that things.
Very recent papers:
· Capps, S.B., Zender, C.S., 2010. The estimated global ocean wind power potential
from QuickScat observations, accounting for turbine characteristics and sitting. Journal of Geophysical Research 115 (D01101), 13. doi:10.1029/2009JD012679.
They give 39TW offshore.
· Lu, X., et al., 2009. Global potential for wind-generated electricity. Proceedings of
the National Academy of Sciences 106 (27), 10933–10938.
They give 78TW onshore. (This is free, if you do not believe me...)
In the literature some give economical, sustainable etc. potentials that reduce that amount. Others authors give other results but when refered to technical potential 100TW is the order of magnitude.
"Second, you need to identify why you chose 1200TW as the maximum wind energy value. Do the other authors you mention above agree with your choice of values?"
Please read before, other people paste here the lines of our paper explaing that. Miller et al. take 980TW citing only one paper. We give 8 cites and only 1270TW and 3600TW are bigger that the 1200 we Take. We take the one of Sorensen because is very detailled and also give turnover times (the only one that we find) that we use latter in the paper.
"I actually agree with this, though have not seen a convincing explanation from you on how you modeled mixing of wind energy from layers above the layer you examined (or will you refer to a specific modeling effort that directly supports your assertions on this matter? If so, please refer to the specific values from said citations). You also note that f3 describes the amount of wind energy that does not interact with the wind turbines, so the unharvested wind energy is still available for capture in Tokyo, as reinforced by layers above the 200m layer you focus on"
Then you agree with me that bottom-up methodologies are flawed. Yes, the unharvested wind energy is still available for capture in Tokyo. We do not modeled the mixing from layers above (and the reverse that you forgive). We reason refering to others as the model of Miller et al 2010 and Wang and Prim (2010) (I expect you could access this two papers). For instance, Wang and Prim (2010) with a general circulation model find that in order to generate 5TWe (therefore interact with around 20-25TW) the ABL power is reduced by 10%. We take the power of ABL as 290TW, that means a reduction of around 29TW similar, even less. That means that the friction at global escale is not compensated by the mixing of the layers above, but that the friction will cause that more energy is transferred to the layers above and not the contrary. The same is when we consider both papers: Wang and Huang (2004) show a 20% increase in the last decades to the ocean waves and McVicar and roderick (2010) less dissipation over terrestrial near surface winds. The most roughness in one area the most winds in other areas...
We take as a first aproximation (we and the referees thing that reasonable and even optimist) that 100TW being dissipated in the first 200m will be constant with or without mills. But, as I remarked here, it deserves more investigation.
You will need to be more specific in explaining just how the papers you cited by Capps and Zender, and Lu et al, provide measurements that are in line with your estimate of 100 TW in the ABL.
Capps and Zender: you claim "They give 39TW offshore". I see no mention of 39TW in the paper, but I do see mention of 37TW - however it is not in any way the same measurement as your 100TW global, instead it is their estimate of electric power generation possible from turbines in a particular set of offshore locations, to quote the paper: "Turbines with 100 m hub heights, 90 m diameter rotors and 3.0 MW rated power placed in wind farms throughout global, ice-free waters no deeper than 200 m and not visible from the coast could generate as much as 37 TW or 50% of total onshore power."
Lu et al: you claim "They give 78TW onshore." I don't see that number anywhere in the paper; the only dissipation estimates I can see are in the section titled "Wind Power Potential Worldwide," based on (admittedly oversimplified) uniform dissipation over the Earth's surface, stating 17.6 TW for the contiguous USA and 340 TW for the planet's land area. (The lower 48 USA has 1/20th of the world's land area, so they clearly refer to 340TW for land not for the global surface area.)
I think the claims you've made from these papers must be from a misreading of them.
retrograde: "You will need to be more specific in explaining just how the papers you cited by Capps and Zender, and Lu et al, provide measurements that are in line with your estimate of 100 TW in the ABL".
The contrary, because I use my estimations as a prove of why their methodology is invalid.
retrograde: "Capps and Zender: you claim "They give 39TW offshore". I see no mention of 39TW in the paper, but I do see mention of 37TW - however it is not in any way the same measurement as your 100TW global, instead it is their estimate of electric power generation possible from turbines in a particular set of offshore locations, to quote the paper: "Turbines with 100 m hub heights, 90 m diameter rotors and 3.0 MW rated power placed in wind farms throughout global, ice-free waters no deeper than 200 m and not visible from the coast could generate as much as 37 TW or 50% of total onshore power.""
I copy the abstract from a draft copy of Capps: "Global o shore wind power is as much as 39 TW (54% of onshore)and is maximized for the smallest and least powerful of the three turbine speci cations
evaluated".
And the important think: (I copy from the conclusions): As much as 0,40% of available 80 m wind power is available to existing technology while wind farms of the future could be exposed to as much as 2,73% of 80 m available wind power". Please do the maths: the 2,73% of 37TW is 1355TW, therefore, the "available 80m wind power" is GREATER THAN THE ENTIRE POWER OF THE ATMOSPHERE! It is obvious that some is very wrong in this methodology.
retrograde: "Lu et al: you claim "They give 78TW onshore." I don't see that number anywhere in the paper; the only dissipation estimates I can see are in the section titled "Wind Power Potential Worldwide," based on (admittedly oversimplified) uniform dissipation over the Earth's surface, stating 17.6 TW for the contiguous USA and 340 TW for the planet's land area. (The lower 48 USA has 1/20th of the world's land area, so they clearly refer to 340TW for land not for the global surface area.)"
I copy again from the abstract: "The analysis indicates that a network of land-based 2.5-megawatt (MW) turbines restricted to nonforested, ice-free, nonurban areas operating at as little as 20% of their rated capacity could supply >40 times current worldwide consumption of electricity, >5 times total global use of energy in all forms". Take the global use of energy in all forms...
So although your own conclusions are in strong disagreement with the Capps and Lu papers, from each of them you derive a measurement that is not directly comparable with your estimate of only 100 TW in the boundary layer, and use it as if it is supporting your estimate. That is simply bizarre.
Can I assume the "1200 TW" from Sorensen is from some recent edition of Bend Sorensen, "Renewable Energy: Physics, Engineering, ... "? If so, it is unusual that you take his 1200 TW without also mentioning the passages in that text that are clearly in direct conflict with your assumptions.
For example, on the 1200 TW which is 2.3 W/m2, Sorensen notes that there have been direct estimates of frictional losses two to five times this amount: "For consistency, the frictional losses must be of equal magnitude, which is not consistent with direct estimated (4--10 W/m2)."
And on the proportion of kinetic energy dissipated in the atmospheric boundary layer, which you claim to be only 1/12th or 0.083, Sorensen has this: "Although the frictional losses of kinetic energy are not confined to the surface layer, a substantial fraction of the losses takes place below a height of 1000 m."
And finally the section titled "Restoration of Wind Profile in Wake and Implications for Turbine Arrays" where he makes mention of transfer of wind energy from higher layers.
Excluding these transfers makes your results meaningless. By the assumptions you make, the innermost turbines of any large wind farm would yield substantially less power than the outermost ones that can spend time closest to the wind. But a simple look at capacity factors of large rectangular arrays like Horns Rev shows this is not the case.
I don't see how it is possible to believe both your results, and the actual generation statistics from large real world wind farms currently in existence.
No retrograde. First: I take 290TW for the ABL not 100TW, 100TW is the power in the first 200m. ABL has not a defined altitud but usually is higher (around 500-1000m). Effectively the more near the surface the more frictional losses. 1200TW is the kinetic dissipation in 20000m, of course 1/100 of the atmosphere (the first 200m) do not take 12TW, but 100TW.
Of course (I do not write the contrary) at local escale behind a real park the power is replenished from above and also from the left and the right in a few km. This, as I reasoned several times here, means that bottom-up methodologies are flawed and is not in contradiction with our estimation. Please read the rest of the discussion here and if possible read our original paper.
Sorry but you are mixing pears and apples in your math, the power you are citing is related to the energy continuously "wasted" in heat by the atmosphere winds, it is a small fraction of the wind accumulated energy, and it is NOT the entire power of the atmosphere that is an unacceptable physics nonsense.
The atmosphere stationary energy regime available for energy harnessing is huge (250000TWh) and continuously renewed and maintained by the sun.
The wind power equipment are unable to affect his magnitude, the wind energy extraction could affect only the air temperature downwind the wind farm of fractions of degree difficult to measure (do the math even for 1 GW farm). The potential for high altitude wind equipments is to have access to this energy reservoir little in advance before the beginning of the wasting process, maintaining a good level of the quality, quantity and availability of this harnessable energy.
The f3 parameter, that you assigned to the KiteGen concept is a clear misunderstanding of the technology, that we define a parachute syndrome.
For instance, Wang and Prim (2010) with a general circulation model find that in order to generate 5TWe (therefore interact with around 20-25TW) the ABL power is reduced by 10%.
I've sifted through the Wang/Prim paper, and cannot find that specific value, especially in the layer up to 200m. They do chart wind energy impacts at the bottom 3 layers (0-30m, 30-60m, and 60-90m) in figure 4, and there is one sentence that you might be referring to, though it refers to precipitation;
Where do the authors provide the data and/or analysis that support your 10% claim above for layers up to 200 meters? Even if the above were correct, extracting 5 TWe is 5 times the amount that you claim is theoretically possible, yet they show that it is indeed possible. How do you reconcile such a conflict?
Also note that the authors are hesitant to make any solid statement about wind energy transfer between layers;
In figure 4 you could take (from run L) the velocity loss and with the average velocity loss from different altitudes you could calculate the power loss. 5TWe (exactly 4,55TWe) is the sum from the different regions of the world for the run L.
They can not resolve the detailed vertical wind profiles, OK, but they do a first aproximation of that. Here I write that this needs more detailed simulations.
Do you mean simply looking at the colored sections of the map and guessing at an aggregation and seat of the pants averaging of the data?? And that's how you arrived at "10%" reduction in wind energy?? I can't believe any scientist would even dream of making such a wild SWAG!
Oh, please. Figure 4 has a graphic an two maps. OBVIOUSLY I take the graph, especifically the black line. Inour paper we do not arrive at 10% we write "more than 10%, from the graph I could demostrate that is more than 10%.
I expect here a little bit of polite. It is time consuming to take time to defend such things that try to attack my honor as scientific.
It would help if you would be clear about what you are referring to (i.e., map versus graphic). And to refer consistently to what you are claiming (i.e., on Sept 7th at 4:12am you state "the ABL power is reduced by 10%", even though this value is related to a model that extracts 5TWe of electricity from global wind resources, which is 500% more than you claim is theoretically possible).
Frankly, you make many statements that are not backed up by empirical calculations (and that includes almost all of your f1+f2+f3+f4+f5+f6 values) and ask people who are trying to understand your claims to calculate the values for themselves by eyeball averaging curves on charts.
Your paper is a start towards a ROM top down modeling effort, but IMO would have a long way to go before it would pass muster at a rigorous scientific or engineering journal.
ATM
Notice that this post is just a summary of the paper; if you are interested in the details you should rather download the paper instead of ranting here
This post is making extraordinary claims that don't hold up to a few simple sniff tests. This is a good place to rant.
The reason for which this article is so important is because it has introduced a different point of view about wind potential beyond the naivest one, which is to take the wind potential of all sites on Earth as independent: that is the very lowest order approximation, which makes only sense if the energy extracted is several orders of magnitude smaller than the total available energy, what is false.
We presently do not take the wind available at one turbine location as independent, that's why turbines are spaced at 5-10 rotor diameters. What the paper is claiming is that a very large wind farm would significantly reduce wind speed within the geographical area and have a down wind effect extending for hundreds of kms rather than 1-2 km. Each turbine in a wind farm extracts about 50% of the energy of the swept area, BUT, because of the spacing and rotor height, only a very small (<5%) of the wind is intercepted by the swept area. Where does the energy come from? Slightly lower wind speed at ground level within a farm so, now the ground intercepts slightly less energy and the turbines slightly more.
Another sniff test,
Accepting 1200TW total wind energy, 1TW is <0.1%, is the author claiming that extracting 0.2% or even 1% is going to have a significant down wind effect.
"is the author claiming that extracting 0.2% or even 1% is going to have a significant down wind effect?". No.
In fact 1TWe is around 4-5TW kinetic, this is around 4-5% of wind power interacting with mills of the total power being dissipated in the first 200m, not two much but not insignificant.
You do not take the wind available at one turbine location as independet but do that at global scale. Mills in parks are spaced (we take this spacing into account) because they try to not reduce more than 2,5% the efficiency of the park. We do not claim that a park reduce significantly the wind extending hundreds of kms, but even 2 km will have a significant effect on the limits for parks at global scale that bottom-up technologies ignore. They take the spaced of 5-10 rotor diameters but apply to every piece of sites of class 3-6 in accesible areas. They take wind velocities in a site, then take wind velocities at other place 2 km behind, then sum the power of this two sites. This is an error. If you claim than the wake effect is not so important beetween parks, then you could do a row of parks wtih lesser an lesser efficies, and if large enough then the wind will go to other place and will dissipate in other place (take the electrical analogy).
I see a row of parks in Almería (Spain) and they are spaced some kms among them (surely two improve the efficiency of each park), with the bottom-up methodologies this space is erased, but this is not realistic even at regional scale. Therefore, industries know perfectly well the first principle.
If your calculations are correct, then the Swedish wind mills are in trouble because the upwind Danish wind farms take a lot of energy out of the wind. Is there any real-world data showing such an effect?
In fact 1TWe is around 4-5TW kinetic
Really? I would have thought that a joule was a joule was a joule. Sure, if we literally convert from electricity to kinetic energy we will lose 50%-80% of the power in the conversion, but does that really apply here??
this is around 4-5% of wind power interacting with mills of the total power being dissipated in the first 200m
But that's not the whole system. The whole system is 1,200TW. And, the 1TW we're discussing is indeed "several orders of magnitude smaller".
Only 1 in 4 or 5 of the kinetic energy of the winds that go to a wind park is converted to net electricity... Some of the kinetic energy is loss in heat and some pass. The whole system do not apply because we never catch with mills the most part. Our source is around 100TW and we could interact directly with around 5% and transform 1%, is not so bad and is reallistic. To interact with around 100TW from a source of 100TW (as bottom-up methodologies do) means that huge and irrealistic energy transfer from above could add to the source (but most part of the source of the kinetic energy is near the surface not the contrary).
Only 1 in 4 or 5 of the kinetic energy of the winds that go to a wind park is converted to net electricity... Some of the kinetic energy is loss in heat and some pass.
I would estimate that for every joule converted to kWhs there is no more than .2 joule of heat, including internal losses within the mechanical and electrical equipment of the windfarm. Would your estimate of heat loss be higher than that?
If some of the kinetic energy passes through the wind farm without being absorbed, then of course that energy is still in the system.
So, that would suggest 1.2TW would be extracted by windfarms, versus 1,200TW in the system.
Our source is around 100TW
That's based on your partition of the sub200m wind kinetic energy, which is in dispute. The overall wind kinetic energy under consideration is 3 orders of magnitude higher (with one estimate is as high as 3,600TW).
huge and irrealistic energy transfer from above
That would be one source. Others include transfer from oceans to land areas; capture of over-ocean energy at coastal areas before arrival on land; higher than average absorption in land and coastal areas with wind farm farms caused by lower than average absorption of wind kinetic energy by ocean surfaces (please note that the subtraction of 60TW of wave energy depends on the previous assumption of independence of wind power below and above the 200m altitude); and a higher than average absorption of wind kinetic energy in a small proportion of land and coastal areas - those already recognized as favorable to wind energy.
My gut feeling is that installed windpower in the developed countries will max out perhaps around double what it is today. If so that's 0.1 TW well short of 1.0 TW. The reasons are economic and political rather than physical. They include NIMBYism, phaseout of subsidies, exhaustion of prime sites, cost of increased connection and eventually the cost of increased complementary measures such as gas backup or energy storage.
For example Australia has about 1.9 GW installed windpower. I'm saying I doubt that will ever get past 4 GW. Already legislation is making it more difficult to build new wind farms in some States. Meanwhile the utilities themselves want the renewable energy targets abolished, just stick to the carbon limits. Developed countries like Japan and Germany that claim to be aggressively pursuing new wind power may lose their way due to these other factors. Perhaps there is some deep connection between the physical limit and the practical limit but as far as I can see they will never get close.
Yes, we tend to think that we will approach automatically the technical limit, but there are ecological, political and economical constraints. I am a little bit more optimistic, and I think we will approach around 0,5TWe, an order of magnitude of expansion and a very important contribution to the global electricity consumption (but only winds will do not save us of peak oil as naively some people think).
How excited should we get about a power generation system that:
1. Relies on current leading-edge technology and resources (including oil) to build, operate and maintain;
and
2. Has a mean time before failure of about 20 years.
?
If we are to invest in inventing any new stuff, it has to be 'legacy' kit that will operate as near to 'in perpetuity' as possible once oil has hit the bottom of the supply curve. Such a legacy will live for generations beyond the end of oil. A modern wind turbine will have failed and become useless long before most of us are gone; so what's the point?
We have limited usable resources, and even more critically we have limited time to use these remaining resources; including the resource of 'smart high-tech thinking'. We can waste it on short-term trash, or we can work on true Legacy Resources to leave to future generations. Our choice.
So you beg the question - what energy conversion/production system operates near to "in perpetuity"?
Wooden windmills and waterwheels made from locally grown timber are not a silly start for an '..in perpetuity..' energy system. The engineering limits on these devices are defined by late 18th century Dutch wind turbines, and they pump a lot of water, grind a lot of grain and turn a good shaft for other purposes. We need to plant the right sort of slow-growing timber and dedicate and protect it for the right purposes so it is there when it is needed; same concept as the Protectors of the Oaks for English Church timbers.
If we could link those to some energy storage system like geared falling mass and other simple media then we will have an off-the-shelf mechanical energy solution to pass on with pride. Fiberglass top end metallurgy and modern electronics all have too brief a life to be of real use a few generations down the back of the Hubert curve.
"Fiberglass top end metallurgy and modern electronics all have too brief a life to be of real use a few generations down the back of the Hubert curve."
I don't think that's really been realistically established. There are some incredibly stable electrical circuits, robust semiconductors, and various plastics, fiberglass fibers and resins that can be locally produced and replaced with no more trouble than the massive woodworks and labor forces that made an old church steeple or windmill.
Stainless steel is simply a wonder, as are Aluminum and Glass! There will very likely still be places where they are produced even with a very deep collapse, and the knowledge of working these materials, no less than our traditions using Brass, Iron and Bronze have been recorded and duplicated so much around the world, that I highly doubt that knowledge will disappear, seeing how we've recovered knowledge from before several prior collapses that existed on very few copies, paintings, imprints, etc..
T-street might think our whole experiment has failed.. but we've managed to pass along our patterns, skills, stories and languages for many thousands of years now.
Take a big breath. This might hurt a bit..
Oil can be synthetised, albeit at a significant cost, but certainly $200 per barrel can be though of.
Having wind slowing down because of all the turbines is a problem i'd like to have.
Although interesting I think this problem is somewhat irrelevant because there is no way you are going to get that many turbines up and running in most countries due to population and environmental factors.
That being said, a reduced population, reduced consumption and adding in solar and some nuclear and that 1TW is perfectly acceptable for a single energy source. I also suspect that we could get that higher in the future given what has been said in the comments.
The focus of this paper on global energy somewhat distracts from a more near term issue in that wind farms are being constructed in rather small areas. We may be a long way from changing the global wind field with wind farms, but in areas such as Texas were many wind farms are being built we may closer than we would like to seeing interference among them.
Earth surface area is 5.1x10^8 km2. Actual radiative forcing caused by CO2 is 1 W/m2. If we extract more energy than this form the atmophere, we will affect the climate in a way equivalent to CO2. This upper limit is 5.1x10^14 W or 510 TW. This is an absolute limit whatever renewable technology you use. However, it can be easily 10 times smaller since energy production is concentrated on 10%.
As a complement of information a similar top down analysis published last years gave an upper limit of 15 TW.
http://www.earth-syst-dynam-discuss.net/1/169/2010/esdd-1-169-2010.html
It amazes me how many comments are killing to the messenger for bringing bad news to the community of renewable illusions.
This is the first time, to the best of my knowledge, that I have seen a top-down analysis for global wind power potential. What is published in TOD is just a summary of what has been published in Energy Policy, after having passed through strict peer reviews.
All the thousands of studies about potential are, most likely, much more flawed, but I have not seen so much criticism in them, like I have seen here.
This is probably due to the way the human mind works: we prefer to listen or read things that fit with our own mindset –and our reptilian brain mindset is always looking for solutions, exits and escape ways- even if they are clearly unrealistic, that if they seem to be more rational, but they clash with our mindset, because they close an exit door.
Obviously, wind power has been presented, from the very beginning, as the most promising alternative, together with solar, to replace fossil fuels…and of course by keeping our way of living.
In this sense, this article is a big setback, because it concludes that all the wind global potential power will, in the best of the cases, cover 25 percent of the present electricity consumption.
Most of the comments here, when confronted with this harsh reality, still try escape forward to the high altitude kite solutions and so or even to install wind farms in the high seas and oceans.
Why don’t we come to reality and before criticizing this article for not having considered the high altitude wind generation, wait to see if at least one kite solution or similar works for a number of years with a sensible EROEI and stable generation and without societal problems?
I suggest to be a little bit more serious when thinking about the technofixes in deep shores or floating windmills or generators connected with kites at several Km. heights. This is what it needs proofs of seriousness before it is given for granted and accounted as potential. In fact, in taking 200 m heights the authors seem to be very optimistic, because the vast majority of wind generators have 80-100 m masts with 40-45 m. blades or smaller.
Almost all the studies on wind energy potential were made, until now, in a bottom-up form, which is at the end much more flawed than the top-down. Because it is very flawed, for instance, to install an anemometer in the Gibraltar Strait area and when they get the results of 2,200 hours a year, to extrapolate that in all the area the 2,200 are granted. This is working when the wind fields are in the range of MW, but it does not imply AT ALL that when going to GW, some unexpected problems may arise, like for instance, winds drifting away by the minimum effort laws if the friction of the whole gigafield is big enough.
The same happens, when experts place anemometers in the Gulf of Cadiz, which is 100 km. form the Gibraltar Strait and extrapolating the results, without considering that a gigafield in the Gibraltar Strait may interfere and reduce the expected arrival of energy.
Some other comments:
1. Why citations are needed for the 1,200 TW of total global wind energy at all levels and in all latitudes? They are cited in the article and besides, if somebody believes that they are flawed, they should prove the contrary.
2. If we are apparently very worried because the possible Climate Change and Global Warming because the increase or change of 1/10,000 in one of the several components of the air on Earth (from 280 to 380 ppm in CO2 that is ONLY one of the components of air), I do not understand those believers thinking that they could easily capture, intercept and transform 15 TW or even much more, out of the 1,200 TW of the air in the planet. This is 1/100 of all the Earth’s wind potential. Why in this case the believers think that there is free lunch in producing such a change at global, planetary level, without consequences for the climate, the ocean streams, the growth of the forests, or many other unexpected repercussions? There is no precaution principle to apply here?
3. I do not really know why Engineer-Poet says that the takeaway of this article is “go nuclear” Could you be more specific where the authors have stated this?
4. With respect to those calculating all the energy in the winds to discard this thesis, I would ask if they have already discounted all the immense amounts of energy which cannot be captured (that below 8 Km/h like the existing many hours in a year in big plains or over 90 Km/h, like the existing in heights of 5,000 m. height or in tropical storms or tornados and hurricanes).
5. Global electricity consumption today is 20,000 TWh (BP Statistical Yearbook 2011)
6.
Spain has installed 20 GW and we know very well what happens in a country with 500,000 km2 territory whose best windfields have already been occupied. Wind fields have been placed in the best possible areas. We started with 2,200 hours/year and are now desperate to find 1,900 hours fields. As I have said before, the proved effiency in Spain in winfields is much higher that that of Germany, with 28 GW, but still insufficient. Generation today is 16% of the total elecgtricity consumed/demanded. And the program is slowed down and almost flat. Many say because political issues, but politics are always linked to economics and economics are usually linked to real world efficiencies. If no subsidies, no installations. And when steel, copper, concrete or other costs are going up, even the improvements in desgin take the prices somehow down, the balance is quite stable and if the installations have to increase price to be offshore or decrease efficiency because the windfield is below 1,900 hours, then the economics do not fit well.
All the thousands of studies about potential are, most likely, much more flawed
I cannot simply assume a wholesale dismissal of all of these other articles based on a weak, overgeneralized 'analysis'.
in taking 200 m heights the authors seem to be very optimistic, because the vast majority of wind generators have 80-100 m masts with 40-45 m. blades or smaller.
What is important is the evolution of turbine heights, instead of counting the ones installed in the 80s and 90s, so 200m is appropriate for land based turbines, though does not take into account the advantages of mountain ridges.
The same happens, when experts place anemometers in the Gulf of Cadiz, which is 100 km. form the Gibraltar Strait and extrapolating the results, without considering that a gigafield in the Gibraltar Strait may interfere and reduce the expected arrival of energy.
The above article doesn't actually address that point, and dodges the point that mixing from the next layer up will 'recharge' the 200m layer to a degree. Has the author performed any 3D fluid dynamics modeling of such interference to justify the amount of interference to be expected, or does he rely completely on Wang and Prinn (2010) findings? If the latter, what specific data and findings were extracted from that article?
I would ask if they have already discounted all the immense amounts of energy which cannot be captured (that below 8 Km/h like the existing many hours in a year in big plains or over 90 Km/h
I would turn that question around and ask how the author above arrived at any such specific figures, or whether a SWAG was simply proffered.
Why citations are needed for the 1,200 TW of total global wind energy at all levels and in all latitudes?
Because this is a key factor in the simple formula presented, and every key factor should have sufficient support.
They are cited in the article and besides, if somebody believes that they are flawed, they should prove the contrary.
We are not the ones proposing a scientific claim - we are asking what the process for identifying and selecting the values for the key factors were chosen, which is the most basic of scientific inquiry.
Global electricity consumption today is 20,000 TWh
You won't find many people here who think that BAU will be in any way sustainable, so projections in demand would automatically be assumed to decline...unless one were a cornucopian.
And we don't discount solar, hydro, and other forms of electricity generation - I don't know anyone who thinks that wind should be used to the absolute exclusion of all other energy production. You have considerable ongoing experience in solar generation, so we would expect you to consider that as a source as well.
Note that a different paper in Energy Policy 'shows' that we will be able to acquire all of our electricity generation needs from renewable sources by 2030 - do we assume they are correct since they went through the Energy Policy peer review process?
http://www.physorg.com/news/2011-01-percent-renewable-energy.html
If you read the paper you will find not only Wang and Prinn being cited. See also:
· Keith, D.W., et al., 2004. The influence of large-scale wind power on global climate. Proceedings of the National Academy of Sciences USA 101 (16115–16120),2004
· Wang, W., Huang, R.X., 2004. Wind energy input to surface waves. Journal of Physical Oceanography 34, 1276–1280.
· McVicar, T.M., Roderick, M.L., 2010. Atmospheric science: winds of change. Nature
Geoscience 3, 747–748. doi:10.1038/ngeo1002.
See the original paper for explanations.
We conclude that we can not diminish the wake effect at global scale. We do the reverse calculation from bottom-up methodologies and conclude that they do not conserve energy and therefore are flawed.
We think that bottom-up methodologies must try to demostrate that they conserve energy.
We do a top-down preliminary assessment because we think (and try to re-demostrate)that bottom-up methodologies are wrong. Our methodology and assesment could not be exact or good, it is open to disscussion, but at least respect the first principle.
A peer review process is not infalible, of course, most papers than we criticized were peer reviewed.
Mark Delucchi work is flawed if bottom-up methodologies are flawed, peer reviews of Delucchi work do not know probably the discussion about this concrete criticism. Our paper claim that is an error to use as presently this methodology, and our reviewers deal with that. Is not exactly comparable.
Of course the discussion will be open, but here, until know, nobody try to demostrate why we are in an error when cite others and do our own calculations showing than bottom-up methodology is flawed. But if we consider than the estimation of the limits of wind power is important, and bottom-up methodology is not the right one, then, why do not try a top-down approach? If you do your top-down approach with the same technical assumptions than Jacobson, Archer, Caldeira, Capps, Lu etc. then you will arrive at much lesser than 1TW (electric). Then, one or both methodologies are flawed.
I see a paper with bottom-up methodologies than conclude: "gross potential outputs were calculated to be... 3368 TW for wave power". But all the entire wave power calculated is around 60TW. Again a demostration that the bottom-up approach is flawed and do not conserve de first principle.
I cannot simply assume a wholesale dismissal of all of these other articles based on a weak, overgeneralized 'analysis'.
That is probably why you must believe that the thousands of studies published by the economicists about the good health of the world economy could never end in the chaos we have these days. Or as we say here: “three trillion flies cannot be mistaken: eat sh.t”
What is important is the evolution of turbine heights, instead of counting the ones installed in the 80s and 90s, so 200m is appropriate for land based turbines, though does not take into account the advantages of mountain ridges.
I think that what is really important is to stick to the facts and realities and understand that in a finite world, nothing, absolutely nothing, can grow indefinitely, including wind generator heights. And with respect to the mountain ridges advantages, have you ever seen where they have been installed in Spain? Precisely, many of them, in mountain ridges in the top of the slopes between plains and plateaus or in the wind corridors like the Gibraltar Strait.
Why citations are needed for the 1,200 TW of total global wind energy at all levels and in all latitudes?
Because this is a key factor in the simple formula presented, and every key factor should have sufficient support.
They are cited in the article and besides, if somebody believes that they are flawed, they should prove the contrary.
We are not the ones proposing a scientific claim - we are asking what the process for identifying and selecting the values for the key factors were chosen, which is the most basic of scientific inquiry.
Perhaps they did not identify so clearly here the citations. The original paper in Energy Policy quotes for this precise figure of 1,200 TW of total energy contained in the winds of the planet to several authors, varying from Gustavson (3,600 TW), Lu et al (340 TW); Lorenz (1,270 TW); Wang and Prim (860 TW); Peixoto and Oort (768 TW); Skinner (350 TW); Sorensen (1,200 TW)and Keith et al (522 TW.
Apart from that, if you still do not trust this figure (I agree with you that the figure of total kinetic energy contained in all the winds of the planet is essential to any study), I can offer you Josep Puig and Joaquim Corominas figures (La ruta de la Energía, 1990) where they assess 1,200 TW for winds, as a subset of the 172,500 TW of the solar energy radiation on Earth, from which all the winds derive. Now, if you have better figures, please let us know. If you need more support, please go to the Enciclopaedia Britannica (Macropedia, Climate and Weather) and see the percentage attributed to “turbulent transfer of heat from surface to atmosphere" and others on the total radiation. I hope that there are no discussions about the size of the Earth and the surface offered to the sun, to calculate how much energy is projected on the planet at 1,359 W/m2 (outer space)
And that of the upper limit of all kinetic energy of the winds is effectively a key figure. All the kinetic energy in the winds of the planet at all heights (up to 30 Km high) and in all latitudes (Northern and Southern Poles, oceans and seas (3/4 of the total surface), inaccessible mountains, national parks (or you want also to fill the Yellowstone with windmills?), etc., etc. represent 1,200 TW, being very optimistic and positive.
Then, if this key figure is finally accepted, and we reach the first mathematical conclusion that capturing, intercepting and transforming 1 TW would mean to divert, brake, slow down or curb 1/1,200 of all the winds in the planet with technofixes. So, we are concerned about changing 1/10,000 of the composition of a component of the air in the planet (280 to 380 ppm of CO2 in the atmosphere) and here we still have many people arguing that diverting, braking, slowing down or curbing 1 TW is ridiculous and that we have potential to divert 100 TW.
Does anybody here really believe that we have the technical possibilities to access to 1/1,200 of all the winds of this planet?
I wonder how is it possible to find so many readers in this page that simply say, to this only figure:
• I suspect that the analysis is actually more wrong than you posit above
• Again, an arbitrary, seemingly random value is set forth as yet another premise with no support.
• 1 TW from all the wind in the world. That's pretty sobering.
• The deficiencies in the quoted analysis aside, I think the takeaway message is "go nuclear".
• It just makes assumptions about this based on...apparently nothing.
• I suspect there may be a flaw, He excludes all the areas we won't get wind from (deep seas etc.), then invokes using up the global resource. I would think the only way you take too much global wind, is if you take wind from all the areas of the world.
• Exactly my thinking. This must be the most obvious error in the piece. Betz law and the 30% interaction with blades also seems like double accounting, but I may be wrong. Also, I agree with the folks that claim it just isn't a reasonable result. 22x is obviously too little.
• I always believed that the very optimistic projections were unrealistic. However, you effectively push back because the analysis doesn't quite pass the smell test.
• Sure Mankind uses a large amount of electricity but compared to renewable's such as wind,solar,wave etc our consumption is negligible.Any one of the major renewable's alone could easily power our needs 100 times over.Only those that have a vested interest in seeing renewable's fail will speak,talk,write,persuade etc against em.
• It just doesn't add up.
• This article seems to be a real stinker.
Come on, a little bit more of reflection and scientific mood on what we can do with the basic elements as the Greek understood them (water, air, fire and land)
Pedro wrote:
That is probably why you must believe that the thousands of studies published by the economicists about the good health of the world economy could never end in the chaos we have these days. Or as we say here: “three trillion flies cannot be mistaken: eat sh.t”
Comparing science to economics is not an effective metaphor, as the latter relies far more on black arts than the former.
I think that what is really important is to stick to the facts and realities and understand that in a finite world, nothing, absolutely nothing, can grow indefinitely, including wind generator heights.
This is a red herring, as no one even remotely suggested that was the case. Rather, your suggestion that the average of the current wind turbine installation set wasn't 200 meters was countered by one where the newest wind turbines are indeed averaging close to that height, and future average heights might indeed surpass this, which actually supported one of the key factors of the article. Also referring the mountain ridge installations in Spain does not exclude the need for the article to address height and other factors in wind turbine sitings, versus assuming some undefined average.
The original paper in Energy Policy quotes for this precise figure of 1,200 TW of total energy contained in the winds of the planet to several authors, varying from Gustavson (3,600 TW), Lu et al (340 TW); Lorenz (1,270 TW); Wang and Prim (860 TW); Peixoto and Oort (768 TW); Skinner (350 TW); Sorensen (1,200 TW)and Keith et al (522 TW....please go to the Enciclopaedia Britannica (Macropedia, Climate and Weather) and see the percentage attributed to “turbulent transfer of heat from surface to atmosphere" and others on the total radiation.
So there still is not explanation for why 1200TW was selected, other than a value was grabbed out of a mix of varying projections. I sincerely hope it was not based on anything in the Enciclopaedia Britannica...
here we still have many people arguing that diverting, braking, slowing down or curbing 1 TW is ridiculous and that we have potential to divert 100 TW...
I haven't seen anyone here saying we would divert 100TW, though I haven't read every comment up to the last few minutes. However, you and Carlos seem to say that harvesting 100TW is ridiculous, so the emphasis should be on you to demonstrate why all the others are wrong, and there is still quite a long way to reach that point with the facts and analysis we have heretofore been presented with.
Does anybody here really believe that we have the technical possibilities to access to 1/1,200 of all the winds of this planet?
Come on, a bit more reflection and scientific mood on what we can do with the basic elements as the Greek understood them (water, air, fire and land).
Carlos wrote;
See the original paper for explanations.
So we receive the brushoff when asking for support for some of your claims. Don't expect us to give much in the way of confidence to said claims, then.
We conclude that we can not diminish the wake effect at global scale.
I don't think anyone argues with that, but the $64,000 question is "To what extent does the wake effect have on downwind wind farms?" You haven't shown us much on this except to discuss energy conservation, without addressing or citing anything specific on the magnitude of those effects within the context of sufficient 3D fluid dynamics modeling.
If you do have a cite and specific values, please share them with us so we can evaluate your claims.
Our methodology and assesment could not be exact or good, it is open to disscussion
This is promising.
peer reviews of Delucchi work do not know probably the discussion about this concrete criticism.
Or perhaps they do and give it far less weight than you do. And perhaps they've seen measurements downwind from windfarms and are more informed on this than yourself. We have to be careful about making too many assumptions.
nobody try to demostrate why we are in an error when cite others and do our own calculations showing than bottom-up methodology is flawed.
I'd love to see the calculations you make on the mixing of energy from the layers above 200m. What exactly are those calculations?
I see a paper with bottom-up methodologies than conclude: "gross potential outputs were calculated to be... 3368 TW for wave power". But all the entire wave power calculated is around 60TW. Again a demostration that the bottom-up approach is flawed and do not conserve de first principle.
One example where (you believe) the bottom up approach is wrong does not invariably paint all bottom up approaches as wrong as well.
I believe this subject merits attention and careful examination of the evidence, though I don't believe (with what has been presented to us) that we are close to an answer yet.
Will Stewart wrote:
So there still is not explanation for why 1200TW was selected, other than a value was grabbed out of a mix of varying projections. I sincerely hope is was not based on anything in the Enciclopaedia Britannica...
If my previous comments of the Carlos de Castro Article as follows:
The original paper in Energy Policy quotes for this precise figure of 1,200 TW of total energy contained in the winds of the planet to several authors, varying from Gustavson (3,600 TW), Lu et al (340 TW); Lorenz (1,270 TW); Wang and Prim (860 TW); Peixoto and Oort (768 TW); Skinner (350 TW); Sorensen (1,200 TW)and Keith et al (522 TW....please go to the Enciclopaedia Britannica (Macropedia, Climate and Weather) and see the percentage attributed to “turbulent transfer of heat from surface to atmosphere" and others on the total radiation.
Plus another quote from two professors of energetic resources in the University of Barcelona also stating 1,200 TW for all the kinetic energy contained in winds does not satisfy you, then I can hardly help.
By the way, you are the first individual I have known despising the Britannica as a serious source.
The selection criteria may well be “I have chosen one of the highest values of the references considered of the people that has devoted a lot of time to search for all the kinetic energy contained in the all winds of the planet, despite the differences among them (geosciences have these things).”. That’s all.
Even better. Chose the 3,600 TW of Gustavson for all the world wind kinetic energy and see if the final, the important, the key conclusion changes very much.
Now, it is your turn to illustrate me on how professor de Castro et al are wrong in choosing 1,200 TW for their calculations. Give us some credible references that can dismantle these above references in several orders of magnitude.
How much you imagine humans could capture/intercept/divert/curb, transform out of this figure?
With all respects, I am afraid you are lost, like many others, in introducing downwind effects for the wind farms, 3D dynamics and other classical subjects, of the typical bottom-up analysis, and you focus on the trees that are hiding the forest. 1,200 TW is the forest. See how much you can harvest from there or show us a bigger, more credible Sherwood.
Give us some credible references that can dismantle these above references in several orders of magnitude.
I would instead have selected a range of values, as there is implicitly quite a broad range in the values Carlos drew from. One answer with so many assumptions about variables often is better supplanted with sensitivity analysis, where a range of possibilities is identified. And a difference of 50% would have made a significant change to the outcome of the estimate - your insistence on 'several orders of magnitude' is an extremely superfluous request.
you are the first individual I have known despising the Britannica as a serious source.
While a fair reference for primary and secondary (perhaps even undergraduate) students, I don't necessarily consider it the best reference for contemporary, peer-reviewed science. YMMV, of course.
How much you imagine humans could capture/intercept/divert/curb, transform out of this figure?
Imagination should never replace solid scientific investigation. How many stars in the universe could you imagine? How many atoms in a grapefruit could you imagine? This does not represent a rational, dispassionate scientific approach.
Since you did not respond to the point about contemporary wind turbine heights, I'll assume you understand and concur with the point.
With all respects, I am afraid you are lost, like many others, in introducing downwind effects for the wind farms, 3D dynamics and other classical subjects
And with all respect, I believe the author and yourself are likewise lost if you do not address 3D fluid dynamics in the context of estimating energy reduction downwind of wind farms - to pretend it is not needed represents a gross oversimplification of the actual problem space. I believe the real reason it was not performed was because it would introduce far more complexity than Carlos chose to undertake (or else it was not sufficiently considered). Yet to ignore mixing effects is to lose sight of the trees...
Trying to avoid and escape the main point of the article with ‘sensitivity analysis’ technicalities.
Get the wide range of references offered by professor De Castro: 350 to 3,600 TW of total kinetic energy in the world winds. This is only one order of magnitude range. Do simple 'sensitivity analysis'. And go to the conclusions that will range between 0.2 to 3 TW of total usable (‘seizable’) energy from the world winds.
That is, between 1 TW and 15 TW of installed power (there are at present 0.2 TW installed power in the world at the end of 2010. BP Statistics 2011), working, in the best cases at 20 percent load factor.
Germany, a world power in wind, had an average of 24.86 GW of installed power in 2009 producing 38.4 TWh; that is a poor 17.6% of load factor or merely 1,540 nominal hours of work per year and Spain, with 17.6 GW installed power in average in 2009 with 37.2 GWh generated, with a load factor of 24%, using both first the best available wind fields, because engineers and promoters are not idiots.
The 0.2 TW installed power worldwide at the end of 2009 were generating about 2% of the world electricity consumption (20,000 TWh).
Draw your own conclusions as whether there are recognizable upper limits in the electricity to be generated by wind in the horizon, and at much lower levels than those usually drawn by the biased industry, multinational NGO's or blind apologists (guts, smells, feelings, etc.) in general, in the classical bottom-up analysis.
Or otherwise, present better, more credible references than professor de Castro, if you have them, instead of finding excuses in the technicalities of “sensitivity analysis”.
Trying to avoid and escape the comments of others about the lack of Carlos' formula taking into account mixing of wind energy from above 200 meters.
I have no problem agreeing to disagree.
No! No! Please! Pedro,
Castro loose his credibility because he is amazingly confusing ENERGY with POWER like a first year student, and you are following the same destiny if you insist with this bold and ideological thinking.
Castro is repetitively claiming that the kinetic ENERGY in the atmosphere is 1200TW<<<<<???
The right figure is about 250000 TWh (*), Terawatthour nor Terawatt, the atmosphere is a huge kinetic energy accumulator like a flywheel.
This special flywheel is continuously refurbished in energy by the sun with a power of 100 - 300 TW and continuously loose 80 TW with the ground orography and the self friction do the rest, up to balancing the apportion with a very strong negative feedback control.
This is a huge advantage for the tropospheric wind power equipments, because we can "plug" the generator everywhere on the planet having locally available a consistent portion of the whole accumulated resource to exploit, without looking for the smaller replenishment flow.
This gigantic accumulator is another huge advantage for high altitude wind exploiting, because this finally close the intermittency issue about renewable sources.
If you want adopt, in your analysis, top down approach you have to look for top - down figures, instead to recover conservative data from bottom up and previous approach, and in any case is required a more holistic attitude and better cognitive performance.
If we want convert this energy in power, I assume for mind exercise, is mandatory to define a time span:
Mankind definitively needs 15 TW (e-heating + e-mobility + e-power_services + e-agriculture)
Atmosphere alone (without sun replenishment and w/o losses) could represent 250000TWh/15TW = 2 years of global energy drawing the full 15TW.
Annihilating all wind energy in a single second the power must be 250000*3600 TW,
or 250000 TW in one hour,
or 10000TW in one day, this should show the boldness and inconsistency of the 1200TW assumption (w/o the 8 days).
Like a light bulb the power is a property of the utilizing device not of the energy source.
Sorry for the stupid examples but it is really stupid what I've just read here.
(*)the mass of the atmosphere is about 5E+18kg the mean wind speed at a mean (mass compensated) altitude (50kPa) is about 20m/s
Kinetic Energy = 1/2*400*5E+18 = 1E+21 J = 270 000 TWh
"This special flywheel is continuously refurbished in energy by the sun with a power of 100 - 300 TW and continuously loose 80 TW with the ground orography and the self friction do the rest, up to balancing the apportion with a very strong negative feedback control."
I've been thinking about this article for a few days now, and I'm not sure that what Gail the Actuary said is wrong. A top down approach seems to be appropriated, and what you've said here seems to support the use of a top down approach.
Lets think about the atmosphere like a flywheel. A certain amount of energy is stored in the atmosphere. Also a certain amount of energy is continually being added to the atmosphere, and a certain amount of energy is continually leaving it. If more energy continually leaves the atmosphere then the amount that enters it the atmosphere will eventually have no stored energy left. From this we can gather that the upward limit on wind power as a renewable energy source is no greater than 100 - 300 TW. Reasoning further we can establish that wind power as a renewable energy source is significantly less then 100 - 300 TW. Not all the energy that leaves the atmosphere will be turned into electricity. Some of it will be lost to ground orography and self friction. Given this reality it could almost be said that wind gathering technologies are in competition with the ground orography and the self friction for the 100 - 300 TW. In considering how much of this 100 -300 TW can be captured for human use the limitations that Gail the Actuary talked about are valid, and the 1 TW upwards limit is not unreasonable.
This appears true. The distribution of wind shear will be moved upward from the ground, and the energy captured by turbines will be reflected as less friction.
That doesn't follow; humanity uses a lot more than 1% of the Net Primary Productivity of plants. Besides, only 15 TW is required. That's reasonably close, a mere 5% of the higher figure.
I hope your right. I suppose even if the upper limit is 1 TW it is still a lot better then nothing.
This special flywheel is continuously refurbished in energy by the sun with a power of 100 - 300 TW
That's much smaller than the claimed 1,200TW. It's very, very small compared to total solar insolation of about 100,000TW.
This seems like a key point. Are you sure? Can you provide sources?
This figures appeared in older studies, prof de Castro here cited a figure I had in mind, abut 60 TW for the ocean wind adsorption that is a confirmation of the order of magnitude.
I should be happy for the new studies that are growing the estimates, but the dramatic variation of the outcomes reveal that this concept is a dependent variable when compared to the atmosphere highly constant energy contents.
A Top-Down approach have to answer mainly to one question: The immense and pretty constant wind energy observed in the atmosphere is maintained by a linear or retroactive phenomena?
I've studied all was available on the topic, and I am confident there is a strong global feedback effect that stabilize the atmosphere energy content, and all the present and future wind power equipments are unable to modify the status.
Total human energy consumption is around 400 quads/yr, or about 13 TW of fuels. Divide by 3 for the equivalent as electricity. 10 TW is about 1700 W/capita over 6 billion people, which is adequate to bring vast numbers to a rather comfortable standard of living.
And I think the reason we are squabbling over the estimate. If max wind is 6%, as the article claims, then we know its only a small BB, and shouldn't get too excited about it. If it is 30% of global needs, thats a pretty impressive size wedge, even if it isn't a magic bullet. And a factor of five uncertainty isn't unreasonable for such a study.
I expect you read at least my responses here. The example of the waves is an other one, not the only one I give here. Please, really do you not see that if an assessment give 3368TW when the entire power is 60TW it is flawed, why do you write in parentesis "(you believe)", don't you? If a bottom up approach gives an absurdity because the methodology employed then ALL the bottom-up approachs needs attention because at least are prone to the same errors, and the errors is at the core of the approach: extrapolate local power measured to the global escale without consideration of energy being extracted.
In OTEC literature:I find that bottom-up methodologies give from 5 to 605TW as the reachable technological power (5 being sustainable, more restricted), but 100TW is the total exergy dissipated in the entire ocean. Again, do you believe in bottom-up methodologies?
The error is in the methodology of bottom-up assessments. I think I presented here enough evidence of that and that all the evidency is in the same direction: bottom-up grossly overestimate the technical potentials of this kind of renewables (is not the same for solar, of course). Please do not ask me for the details of OTEC an other assessments, is a secret ;-) (we want to publish them). If you do not believe me search the literature.
You make a plausible case for contrasting top down estimates with bottom up estimates. Given the large difference with the Miller et al estimate, I believe there are a number of techniques to top down modeling, and that each formula and input value should be carefully scrutinized. I believe very broad assumptions should be treated as such, with a range of values for each input variable factored into an overall range of outputs in a form such as is found in a sensitivity analysis approach.
Yes, but is published in Energy Policy not in an engieener journal. Bottom-up estimations give only one number. My experience is: if you write: 0,2-10TW people authomatically tend to think, OK 10TW is not bad... And I wirte: f2<0,2, f3<... etc. Therefore f2·f3·f4... probably is <<. I mean: 1TWe is an optimistic assessment (at least against the criteria published and not if people think in technologies that are dreams at present) if 100TW is correct for the first 200m and if this number not change so much from the mixing (my hyphothesis). I thing that the mixing from above do not even compensate from the lost due to disipation and the tendency of the winds to flow to not reacheable sites. I agree that this deserves more attention. But if my hyphothesis is not correct and the transfer from above the 200m is considerable in any case the reallity is far away from bottom-up methodologies.
The key concept of this paper is that there is finite limit to the amount of energy that can be extracted from the wind. That should not be astounding, however there is much existing literature which simply assumes installing large numbers of wind machines over wide areas with no consideration of the influence of the machines on the structure of the wind field. As the paper says this is completely ignoring the conservation of energy. This error is fundamental that I could scarcely believe that it had been promulgated in published literature. Nonetheless it is there and this paper is quite correct in pointing it out. While it is possible to argue about the specific factors that have been chosen, the central thesis is clearly correct, and must be taken into account in any realistic evaluation of the potential for wind energy.
Well, on a theoretical level just about everything is finite. On the other hand, what matters is if we're anywhere near that limit, on a practical level: airplane designers aren't worried about the limit imposed by the speed of light.
In this case, I can't see 1TW as significantly depleting a 1,200TW system.
We get to the truth bit by bit. I too suspect that the 1TW global limit is low. On the other hand if you were to consider building 1TW of capacity on say the US Great Plains, the energy balance considerations of this paper need to be taken into account. The Wright brothers didn't worry about the speed of sound.
They didn't, but if their conclusions are correct, nuclear (esp. FBR/LFTR) is the only remaining major energy source available at reasonable cost which can scale in the near term. I say this not as a direct comment on the paper, but as a systems guy.
As Rod Adams said, if the USA had continued to build nuclear plants at the rate of the 70's, the USA would not be burning coal for electricity today. Right now the "Great Green Hope" is wind, but it's actually a much older and less-successful technology than nuclear (the first megawatt-scale wind turbine on the US grid was built before the first controlled nuclear chain reaction). If there are other options on the table, I'd like to know what they are and what they can be expected to do over the next 20 years.
Oh, that is YOUR conclusion.
Can you please illustrate how the nuclear power can scale up in a near term with examples and statistics of the last 30 years? Or by extrapolating the most furious deployments in the 60's to 80's, that will merely give time in the next 30 years to replace the 430 operative ones that have to be decommissioned in the period the new ones have to be installed -10 years average from decision to switch on for each plant-?
Or are we thinking again in a Marshall Plan or hyperManhattan plan to multiply 10 times those rates of the 60's to 80's?
Or the uranium resources available as per the Red Book to feed all tis imaginarium?
How it comes that nuclear power is so economic, if when they have the doors opened to develop and install nuclear plants in the USA or in Spain, nobody gets into the business, unless dad State provides enough securities and backing guarantees to entrepreneurs?
Please observe that I have not used Fukushima as an argument.
See France perhaps.
Let me say this in advance: I'm glad you asked.
It's interesting that you select the last 30 years, because it's been just about that long since the anti-nuclear movement got rolling in a serious way with e.g. MUSE. That momentum is now waning, as people realize that the scenarios of mass deaths have not materialized even from Chernobyl, and major personalities in the green movement such as Patrick Moore and James Lovelock have shifted their stance to pro-nuclear. The last 30 years will, I hope, be seen as a historical aberration.
In the US, plants which were shut down have been re-started, and construction is resuming on units which were mothballed. This trend is already moving.
430 plants over 30 years is less than 15 per year (assuming the same capacity, which is a bad assumption).
It would not take a very high rate of construction to build out a new system in the USA (which is what I will limit my analysis to because I have the data for it). For instance, the USA has enough transuranics in spent nuclear fuel to start approximately 40 GW of fast-breeder reactors. If these were 300 MWe S-PRISMs, the quantity required is about 133 reactors; at the rate of 1/month, building the vessels and such in a factory and shipping complete to the installation site, building out would take about 11 years (followed by a trickle of new plants to consume the on-going flow of SNF from the LWR fleet plus the growth in the fuel supply from breeding). To take care of the whole world, construction would have to speed up to one unit per week. This is roughly the construction pace of low-volume airliners, which are similar in size and complexity.
The fuel supply for S-PRISMs is not an issue. The USA is sitting on almost 500,000 tons of depleted elemental uranium. At a consumption rate of 1 ton per GW-yr, this inventory can supply US electrical consumption for over 1000 years, or total energy demand for over 300 years. The S-PRISM does not scale rapidly, but at GE's projected breeding ratio of 1.22 for a core with axial breeding blankets, the fissionables supply would increase by about 2%/year. This is on the order of the rate of increase in oil extraction which fed the economic expansion of the 20th century.
At the end of 30 years, S-PRISM starts will roughly equal the total output of the end-of-life LWRs which fed them (figure 70 GW), plus about 1 GW for each 60 GW-yr of output from the LWRs still operating (figure 10 GW), plus growth (figure 45% over 19 years from end of the initial ramp). That comes to about 110 GWe, plus about 20 GW of LWRs still running.
FBRs scale too slowly to do the job alone. The Liquid Fluoride Thorium Reactor (LFTR) can do the rest. LFTR can be started on a charge of enriched natural uranium and switch over to 233U bred from thorium. At a fuel consumption rate of 0.9 ton/GW-yr and a fissionable inventory of 1 ton/GWe, less than 2 years of LEU would be needed before the LFTR switched over to thorium. LFTR has faster natural growth (breeding ratio up to 1.07 and much lower fissionable inventory). At a growth rate of 5%/year, the LFTR fleet could double every 14 years. Starting 225 GW of LFTRs over 12.5 years at 300 MWe/unit is 60 units/year or 5 per month, also on the scale of airliner construction rates (the B787 rate is 2-10 per month). The growth rate of 5%/year would continue construction at the rate of around 40/year at the beginning, doubling output to 450 GW by about year 25 of the 30-year period and increasing to about 560 GW by the end.
Note that these two systems can feed each other. The spent LEU from LFTR startups contains some Pu, which can be used to start more S-PRISMs. If the self-scaling efficiency of S-PRISM is sacrificed, it can breed excess 233U instead of 239Pu and each GWe of S-PRISM capacity can start another GWe of LFTR every 5-6 years. That's about 7 GWe/yr of new LFTRs based on 40 GWe of S-PRISMs (ignoring growth from LWR fuel), or an additional 200+ GWe of new LFTRs over the 30 years from program start.
Those are two technologies which are reasonably well understood. Others may do better. If e.g. molten-chloride FBRs are developed, I don't know what they'll be able to do. The combination of on-line reprocessing (no inventory stuck in fuel cooling and refabrication) and purging of xenon from the core should improve the scaling rate a lot.
More like Moore's Law. Everything gets smaller (mining rates, waste stockpiles, physical system sizes) except the power output. Going from a billion tons a year of coal to a few hundred tons/year of thorium plus uranium from inventory is a huge reduction.
S-PRISM requires no new uranium. Running 36 GWe average of LFTRs on LEU over 12.5 years to establish the initial 225 GW fleet takes around 10,000 tons/year of uranium. Natural growth takes no uranium, just thorium.
Because "dad State" has a history of changing its mind every 4 years, or whenever certain pols get paid to throw spanners in the works. If the state pays a price for changing its mind, those changes are less likely and the investment is quite a bit safer.
That's good, because the relatively benign effects turned George Monbiot into a supporter.
I see he wrote that back in March, and uses only body-count as his yardstick.
He ignores the wastelands, and compensation, and insurance issues this raises.
Those domino effects will matter far more, in the long term, than any semantics over body counts. as far as we know, no one has yet received a lethal dose of radiation. Wow, so that means we can ignore the rest ?!
Rather misses the point, as he is not trying to sell a house in Fukushima.
The (surviving) houses in Fukushima are not at risk; they can be decontaminated too easily. Particles can be detected and removed, topsoil can be covered or replaced.
The real issue is farmland, and how much Sr-90 is tolerable. There are solutions to that too; grow a few crops of something which takes up a lot of calcium (which strontium mimics) and throw it away, then add lots of lime to the soil to make the strontium less likely to be taken up. All the while, Sr-90 is decaying. A "wasteland" which is twice the limit for crops falls under the threshold in 30 years. That's the beauty of these things; they go away just by ignoring them.
France decided to replace it's mainly oil based electric power in 1973, due to the oil crisis. In 1992, it had reached 75% nuclear. That's 19 years.
1985, according to WNA nuclear reactor database, saw the commercial operation start of some 42 reactors. Nowadays, each reactor is bigger and we should be able to build even faster after a ramping period.
Economically extractable mineral resources never "last" more than a hundred years, because you won't prospect more than that. But we can pay a hell of a lot more for uranium, so reserves can be expanded an order of a magnitude, at least.
Because coal is cheap and because the doors aren't really that open - the remaining regulatory burden on nuclear is overwhelming. If it is not partly compensated by guarantees, it's a no-go.
Because coal is cheap and because the doors aren't really that open - the remaining regulatory burden on nuclear is overwhelming. If it is not partly compensated by guarantees, it's a no-go.
Ah, I see, but regulatory burdens do imply an extra cost isn’t it? Traffic lights cost me some extra gas in the car in ticking over position and I may disagree and blame on regulators that if they remove them, I could drive more efficiently. Specially if dad State is going to cover and ensure all the accidents and clashes for lack of regulations in the crossroads.
Sure, and if you had traffic lights every five meters with 5 minutes tick-time, driving would be even more safe. And why not make it so? We can have motorcycles and let them ignore traffic lights, and thus the problem is solved! Sure, we have regulated that motorcyclists need helmets, so we've done something there too.
In such a framework, we shouldn't be surprised that motorcycles dominate, and we shouldn't be surprised about a high level of traffic casualities, and we shouldn't, perhaps, blame cars for their inferior penetration. This is the case with nuclear vs coal/ng now. We typically regulate new nuclear out of existence, but let coal go relatively free, even though coal is the greater killer by far.
This is simply a matter of finding an optimum regulatatory environment. Human psychology and its influence on democratic institutions obviously stops us from finding such an optimum. The distant threat of climate doom and the slow grind of coal cancers has less psychological weight than the spectacular accidents of Fukushima, Chernobyl and TMI. Not much to do about this, actually, we've only to wait until conditions change.
Oh, I see. Now you blame on the own industry regulations and on the governments that did the permits to install the 440 operative nuclear plants of posing NOW too many hurdles to the nuclear industry. Apparently you know much better than them where is the fulcrum of the level of due guarantees for the nuclear plants and who has to support them. Or better than the Traffic Departments to decide how frequent the traffic lights have to be installed, to find an optimum.
Now put in money the amount of the Chernobyl issue or Fukushima and let the industry pay for the present and future damage. I am not defending the coal industry for the reason that I do not believe that a shit can give an alibi to another shit, so you are free also to include environmental prices of coal to the price of coal fired power plants.
Yes, precisely. I do, and I do.
I believe it can, when there are no real alternatives.
I think his "logic" is fallacious; it amounts to "if everything has flaws, we should do nothing."
Wind is limited mostly by physics and engineering. Nuclear (esp. the radically different reactor types which would eliminate most of the things the anti-nukes claim to be worried about) is limited mostly by government obstruction. What's easier to get out of the way... hmmm....
There are no regulations or government obstructions standing in the way of better reactor design. The French, Iranians, North Koreans and Chinese are willing to build just about anything, to name a few countries.
Nuclear is limited by cost, having no solution to the waste problem, and being a dangerous process under the control of humans. No matter how good a system you think you've created, there will always be a Homer who can screw it up.
Of course it is. How the heck are you going to get a new design certified, even?
What? The French are very particular. The Iranians and the North Koreans have built like one or two reactors each, and are not even relevant in this context. The Chinese are ramping so fast and so much that they don't want to put all eggs in one basket. And China is a proof of my point, they are "willing to build just about anything", and thus they do it rapidly and cheaply. The US is looking at five times the cost, partly because of regulatory burdens.
The waste problem is solved. (If you don't know that, you don't know much about nuclear power.) Sure, humans can screw it up, and so can faulty designs. That should be acceptable, as nuclear accidents are a smaller problem than the drawbacks of alternatives.
You are making some interesting claims which, for me, require proof.
Regulations for nuclear plants have been very streamlined over the last several years. The cost of nuclear comes basically from construction and financing costs. Please show some proof that regulations add more than a small fraction of the overall costs.
We have, as far as I know, no solution for used nuclear fuel except to store it in pools or encapsulate it. Both temporary solutions. We do not have the ability to refine/reuse that fuel in a cost efficient manner. We have no solution for the non-fuel nuclear waste, nor a way to decommission worn out reactors. We are letting them rot in place.
I see absolutely no reason to accept another Chernobyl or Fukishima. Not even a Three Mile Island or Davis-Bessie or Browns Ferry. There is nothing acceptable about meltdowns or even near misses when the safer alternatives provide cheaper power and can be brought on line much faster.
There is so much to say about this, but unfortunately, being an interested Swede I don't have all the details and don't have the time to dig it all up. I'll hand-wave a bit, and fully expect you to dismiss it out of hand: First, you regulate electric utilities, keep electric utilities fragmented and unable to accumulate funds to construct nukes. Second, you demand design certification and probably have lots of over-the-top worker certifications and so on. Then I guess you demand lots of paperwork, lots of inspections and so on, and transfer the costs to the build. Then, there is a certain political risk with building nukes. What if the scene changes and the plant isn't allowed to start? All this adds to risk and adds to costs. If the Chinese can do it for $2 and you need $10, when most of the costs should be hardware, then that has to have a cause. What, if not more regulatory overhead?
I mentioned the Swedish KBS-3 method. It is so safe that it's ridiculous. As a Swedish taxpayer, I'm actually a bit mad the method is so over-researched and overdimensioned.
Of course you do. You have just chosen not to. (Ok, virgin uranium is a bit cheaper, so depending on definition, you're right about it not being "cost-efficient".)
What are you talking about? Yankee Rowe, Main Yankee and Connecticut Yankee have, AFAWK (As Far As Wikipedia Knows), all been dismantled and restored to green field status. It's just so that dismantling obviously becomes cheaper and easier if you wait, so many does just that.
To me, it's obvious that intermittent sources (wind/solar) can't scale very far, and that biofuels doesn't suffice and is less environmentally sound to use than enduring a few nuclear meltdowns. But perhaps you are thinking of coal and NG as cheaper, faster and safer?
The first ten percent wind may be relatively cheap, but for more, when you need to lower NG plant utilization, need better transmission and get low spot prices when the wind really blows best, it gets more expensive. Above 20% penetration, when the spot price of the best wind days is often zero or negative, what do you do?
You won't get anywhere trying to use the Chinese price to project what nuclear could be built for in the US. Try using numbers from Olkiluoto which is being built by Areva, a very experienced reactor construction company.
China pays beans for labor. Last time I checked a carpenter/skilled worker makes about $100 per month, an engineer makes about $200 per month. Those are hourly wages (including overhead) in the west.
Around half of the cost of a new reactor in the west is financing. China is paying cash out of pocket, so double their price to see what a new reactor in the west should cost.
Then look at the open bids for new reactors in Ontario and San Antonio. They came in around $10 billion for a turn-key, all-in build. Turkey asked for a guaranteed kWh price and received a bid of $0.21/kWh. Those are real numbers for building reactors outside of command economies. Those prices are not due to paperwork, they are due to real construction costs and real financing costs.
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Wind? Part of the answer, part of the grid mix.
Here, look at the simulations of summer and winter grid behavior based on actual data...
http://www.stanford.edu/~ehart/AWEA_Poster_Hart_final.pdf
Those are short term simulations, only five years from now. Use your imagination and build in some tidal (it's already working), more solar and wind and some storage to eliminate/greatly reduce the coal and natural gas.
Solar is getting cheaper, on the way to cheap. Storage we can build when we get to the point we need it. That's several years from now before we need additional storage. EVs and load-shifting will deal with input peaks, providing profitable markets and allowing larger builds. The western grid can absorb up to 30% wind and 5% solar (before EVs) until it needs more storage.
Transmission is an infrastructure that we are going to have to bear. We built railroads for coal, we'll have to build transmission for wind. Once built, those transmission lines serve us for many, many decades, to price them out for a 20 recovery is incorrect.
Anti-nukers are always referring to Olkiluoto, which is a botched project with a first-of-a-kind reactor with great delays, much of them due to problems with regulators. However, China, Japan and South Korea seem to be able to build on time and on budget. France have been doing it as well.
If half the cost of a western reactor is financing, perhaps this is a problem that needs to be adressed if a society needs long-lived investments?
Perhaps you should check Chinese labour costs again. They are rising rapidly and differ wildly depending on location.
$10 billion? Was that for a pair, or for one? South Korea recently sold four turn-key APR-1400 to UAE for $20 billion.
Yes, that's the typical defense: "The mix will fix it." It won't. Wind will remain an alibi for coal, or, at best, an extension of NG that replace some coal. All the while we are moving closer to a climate doom that could be avoided with nuclear power.
If half the cost of a western reactor is financing, perhaps this is a problem that needs to be adressed if a society needs long-lived investments?
Probably. The same logic applies to wind, solar, and all the other high capex alternatives to FF.
"The mix will fix it." It won't.
Ahem...sure it will. Heck, every source depends on the grid. Nuclear certainly does.
True. The Combined Operating License eliminated the approval step after construction is complete. This prevents legal shenanigans such as preventing a completed plant from starting; if it is certified as being constructed to spec, it has an automatic go-ahead. (Needless to say, this kind of obstructionism led to huge cost overruns as utilities had to pay interest on bonds for finished plants they could not start.)
The COL created a flurry of activity in the US nuclear industry. You can track the activity of the permits at the NRC Combined Operating License applications page. I count applications for 28 reactors on it.
And horrendous regulatory costs, consisting of checking and re-checking everything and documenting it. In the aircraft industry, there's a saying: "The airplane isn't ready to fly until the paperwork weighs as much as the airplane." Nuclear is probably worse, because the NRC does not have any consideration of the health of the industry or the consequences of the alternatives in its charter.
All the transuranics can be turned to energy in e.g. an Integral Fast Reactor. The fission products become less radiotoxic than the original ore in about 500 years.
There is a lot you don't know about, starting with pyroprocessing.
Would you rather see 400,000 per year die of pulmonary effects of coal as in China, or the entire world's climate shift so that whole ecosystems die off and billions starve as food can no longer be grown where the good soil is... or was?
Refuted here, so I won't repeat myself.
Integral fast reactors - are there any in commercial use or is this a "might work"?
How much pyroprocessing is ongoing today and what are the costs? How effective? What is the fuel requirement?
Now, I'm all for research. I would like to see some money spent to see if we can solve the problems with nuclear, but I'm more interested in getting fossil fuels off our grid and off our roads. That means using what we have up and running today, not what we might perfect sometime in the future.
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The choice is not coal or nuclear. That is a false argument pushed by the nuclear industry. Renewables with storage are clearly a third option.
Do you want to claim that nuclear is safer than wind or solar?
Can you provide a reliable set of figures which shows that new nuclear is less than the $0.05/kWh for wind or the $0.15/kWh and falling rapidly for solar?
Can you show how a new nuclear plant can be brought on line in two years or less - wind farm time or in a few months - large solar array?
How would you deal with the lack of forges for containment vessels? How about the lack of trained and experienced engineers and technicians? How would we get from having problems staffing the reactors we have now to some sort of super build out?
Can you identify several hundred locations in the US where new reactors might be built? Be sure to pick places where local populations would permit one in their backyards and make sure there is adequate cooling water available.
The project to build and prove IFR was killed by the Clinton administration in concert with John Kerry in the Senate in 1994. Refunding Japan's contribution to the project cost more than running it to completion; it was done specifically to close that road.
You can find papers on the results of pyroprocessing at the ANL web site. They have been doing small-scale tests with the fuel taken from the Experimental Breeder Reactor II. The IFR project was set to prove the process at industrial scale, but the termination ended that effort. Politics, not chemistry. Pyroprocessing shares a lot with the fuel cycle used in the Molten Salt Reactor Experiment (MSRE).
That would be light-water reactors, for the most part.
The storage capable of storing even a week's worth of wind power (CAES) requires natural gas to re-heat the air. That's not renewable.
If you compare deaths per megawatt-hour, nuclear is far safer than wind or rooftop PV.
Whoa, you're comparing whenever-it-blows wind to baseload nuclear power. Add storage costs plus other required feedstocks for wind to meet the same availability spec; they won't be trivial. Also don't forget to eliminate the 400% NRC tax, which we can remove whenever we get the political will.
I'll do it as soon as you show me how a wind farm or solar array can continue generation at 100% through nights, cloudy weeks and stationary high-pressure systems.
Oh, that's easy. Build IFRs and MSRs. Their coolants are liquid sodium and molten salts respectively, and they require no pressurization. No pressurization, no forged pressure vessels, no containment buildings required to hold ruptures of steam systems.
Molten salt reactors in particular are self-regulating for the most part (the core goes sub-critical past a certain temperature as the fuel expands), and should require far less expert intervention than today's naval-derived light-water devices.
Make 'em dumb enough that staff don't have to be hot-shots. The MSRE was a great example of this; the project didn't have the budget for 24/7 operation, so the last Friday shift drained the reactor into the dump tanks before leaving and the first Monday shift pumped the salt back into it and fired it right back up.
There are dozens of existing reactor sites, some decommissioned reactor sites, and hundreds of sites for current or decommissioned coal-fired plants. Many probably still have the transmission line rights-of-way and cooling water.
Cooling water may not be required. With some sacrifice in thermal efficiency, dry cooling towers or open-cycle gas turbines can be used instead of conventional steam turbines. The very high operating temperature of molten-salt reactors is particularly suitable for this option.
This assertion is so wrong as to be risible. Here's one expert appraisal just to start you off: "NRC Regulation is directly responsible for pricing up US nuclear reactors by 400% relative to the cost of nuclear in 1973 at the end of the AEC regulatory era."
NRC rules and its enabling legislation require the nuclear industry to pay to train NRC personnel in the matters they are to "regulate". IIRC (my search efforts aren't turning up a reference) GE has calculated that just the NRC training for a new reactor type like the S-PRISM would cost $1 billion and take 5 years. That's 5 years and $1 billion, before any construction proposals could be submitted for review by the new personnel. Worse, they don't need any justification for demanding niggling changes (which can cause safety issues, like TMI Unit 2) or just plain saying "no". Would YOU invest money with that kind of risk?
The Chinese have purchased a Russian BN-800 (LMFBR, 880 MWe) and announced that they intend to pick up with MSR research where the US left off in the early 1970's.
Due to the anti-nukes behind the creation and operation of the NRC, these technologies will reach market literally 2-4 DECADES after they could have, and the USA will be the last to get them instead of the market leader.
*saving for reference* Thanks.
As much as I support the nuclear power industry. The public was not ready at all for that kind of technology, especially when you combine the word "experimental" and "nuclear" in the same sentence.
The Monju suffered major public relation problems following a sodium fire. Whether it was dangerous or not (probably not), the industry couldn't explain themselves following the public uproar.
Whatever you build, you must be ready to explain yourself following problems, mistakes. That is, assuming the political cost of doing such thing. You better be right or else you are likely to lose the public trust... and your job.
The NRC is simply taking their time, at least until the market conditions are politically/socially favorable, they just don't want to take risks for the industry.
Funny, I thought the whole point of putting up these articles was to have them discussed and critiqued by a range of people and professions. His article is being treated with the same (if not less) skepticism than the previous article on floating solar panels.
This is as it should be.
From willstewart's comment above:
The strangle hold that scientific publishers have on publicly funded science is a sad state of affairs in my book and one of the reasons I have devoted so much time to The Oil Drum. Disappointingly, scientific careers and street cred still come primarily from "refereed publications" and not from a presence in the blogosphere.
I think the authors of this paper deserve at least a little credit for taking the extra time to create a condensed version of their paper for publication on TOD and for participating in the discussion. Unfortunately, we cannot present too much of the original article in this space without risk of copyright infringement. Thus the disconnect between the readers' requests for more information and the authors' response of "read the paper".
There is no immediate solution to this problem but I would encourage everyone weighing in (commenters and authors) to understand that we are operating at the interface between two very different cultures: fast moving, free wheeling, frequently off-topic but always free internet debate vs. slower, more methodical, hierarchically controlled and too often behind-a-paywall scientific discourse.
TOD readers are a very intelligent, very insightful bunch. But some comments can veer toward ad hominem. Lets try to keep that to a minimum. I would like to see more more articles of this nature that summarize recent scientific publications. TOD is a very unique forum for vetting the ideas and results presented. I sincerely hope that readers can have a little understanding why authors do not wish to duplicate work they have already done. Similarly, I expect authors to understand that referencing an article that exists behind a paywall can sound a awful lot like "Screw you." to a large fraction of the TOD readership. Everyone needs to do a little more work at this science-internet interface but the end result is worth it IMHO.
If anyone is interested in some recent commentary on scientific publishing, the following posts are notable:
Is scientific publishing about to be disrupted (Jun 29, 2009)
Why Hasn't Scientific Publishing Been Disrupted Already? (Jan 04, 2010)
Best Hopes for free, open and civil scientific discourse!
Jon
Jon, thanks for this thoughtful perspective.
OK, here's a start at taking a stab at the science-internet interface...
http://www.earth-syst-dynam.net/2/1/2011/esd-2-1-2011.pdf
http://www.earth-syst-dynam-discuss.net/1/C84/2010/esdd-1-C84-2010-suppl...
Indeed. As a layperson trying to get a grasp as to the validity of the conclusions of this paper it seems that the experts in the field have yet to reach a consensus as to the true upper limits of energy that can be extracted from wind without causing serious damage to the climate and the ecosphere... How am I supposed to make any sense of the following?
See before. Miller et al reinforce our results.
Miller et al also follow a top down approach, but their conclusions are starkly different from yours;
Note they are modeling 10 layers, whereas Wang and Prim only looked at the bottom 3 layers (up to 90m). Hence, their inclusion of layers above the wind turbines lends credence to the comments by others here that migration of energy from layers above the wind turbines must be taken into consideration.
Please, read before. ¡!
In our paper:
"...referred to in Table 1, and is only comparable to the estimation by Smil (2008) ( <10 TW), except for the physical–geographical potential estimated by Miller et al. (2010), also using a
top–down methodology, which is 17–38 TW (our physical–geographical potential, applying only f1, f2 and f6, which is comparable to Miller et al. (2010)’s methodology and calculations, would be <40 TW). This means that technological wind power potential imposes an important limit on the effective electric
wind power that could be developed, against the common thinking of no technological constraints by economic, ecological or other assessments".
Miller et al. +f3+f4+f5 that they do not take into account will give 0,5-1TWe, even less than our limit.
Miller et al. paper reinforce our results not the contrary.
They most certainly take f3 into consideration, the power extracted by wind turbines was also included in the modeling runs;
f4 relies too heavily on assumptions that land with class 3 winds is as important land with class 5 and 6 - as the power in wind is related to the cube of the wind speed, the higher wind sites obviously hold the lion's share of extractable wind energy, even if they were a low percentage of the land at class 3 and above. So this factor is not carefully or empirically analyzed in your paper.
f5 you have estimated at .75 (without any real support), but even if that were the case, it would only drop Miller et all by 25%, which would still give 13 - 51TW.
And looking at their simple momentum balance model (which is their shorthand method for understanding the maximum extraction of wind energy), they still support over a order of magnitude higher estimate than your paper;
Factoring in the mechanical to electrical conversion rate (let's be conservative and say 85%) will still give over 17TW.
In any case F4 is not 1 as you are assuming in your recalculation. And sorry but class 3 winds have aproximately the same power than superior classes (less power per area but a lot more area), we follow the Archer and Jacobson results. Therefore 17TW/2 = 8,5TW
F5=0,75 (an optimistic one), therefore 8,5*0,75=6,4TW
Factoring the conversion rate (0,85 to me is not so conservative if you take EROEI, maintenance, faillures, transmision lines etc.): 6,4·0,85 = 5,4 TW
For Miller et al. the accesible wind is in the ABL that is bigger than 200m accesible to real mills, ABL power is 290TW not the 100TW we take this into account = 1,86.
Miller et al do not disccount the wind that is lost beetween mills and behind blades that is more than half...
In an other way: I paste Miller (higher results):
2. 900 TW ≈ total wind power generation rate in the global atmosphere (Lorenz,
1955) is the upper limit available for wind power extraction (Gustavson, 1979);
3. 450 TW ≈ 1/2 of this wind power is dissipated in the atmospheric boundary layer
(Peixoto and Oort, 1992)
4. 113 TW ≈ 1/4 of the global surface is non-glaciated land making it most accessible
for extraction;
5. 38 TW ≈ 1/3 of the available power can be converted to mechanical power that
drives the wind turbine as shown by Garrett (2007), an extension of previous
studies from almost 100 years ago (Lanchester, 1915; Betz, 1920).
(the important think is that this very simple estimate invalidates bottom-up methodology)
ABL is higher than the mills.
They supose that all the surface non-glaciated is accessible and that all that surface will be covered with mills without any distance among them.
I have not assumed f4 is 1, I merely quoted one of your key references directly.
By jumping from reference to reference, it is not easy to follow your train of thought. You seem to agree that a range of values may be valid, from 6.4 to 38 TW.
the important think is that this very simple estimate invalidates bottom-up methodology
You are getting closer to making that case, though I believe there is more refinement necessary to address some of the comments from reader/reviewers here.
In the picture below, what would you surmise that f4 would be?
I believe I have vacation pics of that wind farm. SSE of Silicon Valley just off I-5, if I'm not mistaken.
While I have no idea of the existing situation, in the pre-internet age it was traditional for authors of scientific papers in most fields to send offprints of these papers to anyone who requested them.
Has this tradition died?
Can the authors of this paper do this for TOD readers who are interested?
carcas at sid (dot) eup (dot) uva (dot) es
Europe's On- and Offshore Wind energy potential is 75'000 TWh.
This is about 18 times Europe's electricity demand.
That is another bottom-up study. That is the big difference with what has eben published here.
When I see European or national wind power potential maps or solar irradiation maps, I believe we are not being serious.
At lest with sun, in the experience we have in Spain with 4.3 GW installed power and 5 big differentiated areas by the Administration and very long experience in irradiation for decades and with solid data bases, the differences are not very high between a place and a neighbouring one. In some cases, there are occasional fogs, mists or other local factors (i.e. very windy areas in installations with two axis trackers) that reduce the nominal original considered irradiance in a map in a 10%.
But in the wind sector, these maps are for beginers and believers. A wind farm placed in the top of a ridge may generate as expected and 200 m. below this level in the slope, at 500 m. distance, a similar installed power may generate half of this amount. Therefore painted maps are to create illusions of many available square miles or kilometers. The promoters know that even placing anemometers along the precise edge of the ridge for a couple of years is sometimes not enough to be sure.
Accesses are another pain in the neck for many sites with potential. It is curious that this study has taken the distance to a grid (usually in Spain wind farms connected to 120 kV power lines or higher) as a limiting factor, despite that here some have laid 20 Km new power lines to get into the grid. These are the costs (energy costs; I am talking about EROEI) that are hardly accounted.
The Northern Africa West coast and Canary islands are excellent because the trade winds. But Canary islands have a lot of urban, expensive soil; another important percentage of national parks and an orography impossible for many other paerks. The sea bed is so abrupt that there are almost no prospects for offshore parks. The islands have also important limiting factors in the percentage of intermittent, stochastic energy that is admitted within each autonomous (in generation) island.
I have been discussing with the Moroccan authorities to take wind and solar energy from Morocco to the Canary islands (submarine cable connected to the Moroccan national grid) to improve the "cushion" and there are important political (i.e Western Sahara or a cable as long as unfeasible), financial, technical and economic constraints.
Desertec has beautiful drawings of energy flows coming from northern Africa to Europe to satisfy zillions of homes. Still in the drawers. Not even the tariffs have been agreed upon. The part of the cake of the land owners is not negligible. The portion to be left locally makes some projects not feasible. The power lines, apart from needing HVDC huge and very thick cables, as to imaging a gigantic jump rope for all the vessels and submarines crossing the gibraltar Strait to play the game. Then, they have to meet the reluctancy of Spain and France (specially France), to give rights of way for this energy to arrive to Germany and the rest of Central Europe, where the big demand is, and also to decide how much they want to keep for themselves and how much tthey want to invest for that. Or for Italy to give rights of way to Germany of the energy generated in Tunisia, being Germany one of the most important promoters, not to talk on the energy lost in the way, the dependency issues of sometimes unstable countries. It resembles me very, very much to the war games with the Russian gas passing through so many countries in its way to the wealthy Western Europe.
I am amazed when I see people calculating so easily in bottom-up form, with the theoretical data.
I'm amazed when people make studies that basically claim that wind hardly exists.
(Since mountain ranges, forests, cities etc. create orders of magnitudes more friction than the number of wind farms in the study mentioned above ever could).
And I'm amazed when people make studies that basically claim that existing wind farms produce far less energy than what they in fact produce and are getting paid for.
And as far costs are concerned: Wind farms must be pretty competitive otherwise they wouldn't exist: http://www.greentechmedia.com/articles/read/how-did-wind-beat-the-price-...
Germany one of the most important promoters, not to talk on the energy lost in the way, the dependency issues of sometimes unstable countries.
Which is why Germany is looking for oil and gas in Bavaria, instead of importing it?
Besides Germany does not need Desertec anyway:
http://www.umweltrat.de/SharedDocs/Downloads/DE/02_Sondergutachten/2011_...
http://www.umweltdaten.de/publikationen/fpdf-l/3997.pdf
I'm amazed when people make studies that basically claim that wind hardly exists.
(Since mountain ranges, forests, cities etc. create orders of magnitudes more friction than the number of wind farms in the study mentioned above ever could).
This article talks about 1,200 TW for kinetic wind energy worldwide. It can hardly ‘harldy exists’
Mountains, forests, cities, etc. create friction, as ever since Earth has mountains, forests, cities, etc. exist. That is why we have forests (wind helps to move leafs, interacts with oceans and seas to create waves that create marine life, stabilizes climate, etc., etc., etc.
That is why we have (probably we had) with these frictions, among other natural things, like the sun rays, the evaporation, etc. the wonderful world we have today.
If we recognize that the human attempts to capture energy with wind generators are targeting the wind power to replace in the medium term a significant percentage of the dwindling, limited and depleting fossil fuels or uranium (about 10 billion Toes/year now), as per the own wind industry and apologists are claiming, then we are talking about the need to install, not the 0.2 TW of today in wind power (2 percent of the world electricity), but something probably between, let us say 40 percent of the world electricity and/or 30% of the primary energy. This is if we believe that wind energy is something else than Micky Mouse games.
And this will require between 5 TW and 12-15 TW of wind installed power, working at 20% load factor (if possible). This represents between 1 TW and 5 TW of captured energy from wind IN A NEW, DIFFERENT FORM than the natural friction with the Earth surface natural elements.
And this is a newcomer interference of between 1/1,200 and 15/1,200, which is a butterfly effect much bigger (10 to 130 times) than the effect that today worries to thousands of specialists in Climate Change and Global Warming, for the introduction of an extra 1/10,000 of a single component of the air: the CO2 from 280 to 380 ppm.
That is why, not to enter in the feasibility and materials and financing and many other things required to put 10 TW wind power in place.
Calculate the area of all those wind blades.
Calculate the surface of one side of every tall building we've stuck up in the wind.
Explain to me why the breezes still blow....
!!!???
In fairness to Pedro, the influence of the blades extends over the entire disc of rotation, not just their own projected area.
IN A NEW, DIFFERENT FORM than the natural friction with the Earth surface natural elements.
So you are basically claiming that not only water in a small glass can supposedly be 'memorized', but even a tiny fraction of air diluted in a vast atmosphere can supposedly 'memorize' the entire atmosphere:
http://en.wikipedia.org/wiki/Water_memory
Well, go ahead and proof it, since:
Extraordinary claims require extraordinary proof!
Though your meaning is quite obscure, I take it your intention is to express doubts about the liklihood of AGW? And your entire reasoning amounts to something like "Well, an extra 100 ppmv of a gas added to earths atmosphere doesn't sound like very much to me"?
So clarify for me, exactly WHY should we read your opinions on a technical topic? LOL
The meaning is quite clear, for those who want to understand.
The change by anthropogenic means from 280 ppm to 380 ppm of CO2 in the composition of the air in the planet, has mounted a huge paraphernalia of thousands of scientists analyzing and observing that this minor change could seriously affect to Planet Earth in a severe, irreversible form (Climate Change and global Warming). Being CO2, in its turn just a 0.035% of the total air composition.
By mentioning this, I am not, by any means, expressing doubt on the likelihood of the Anthropogenic global Warming. Very much on the contrary. What I try to leave crystal clear is that minor changes (meaning by minor change to increase the CO2 in nature in 1/10,000 being CO2 in its turn 0.035% of the air) in the composition of the natural environment in which we live, may cause huge, irreversible disasters.
So that the precaution principle has to be always considered, when analyzing anthropogenic transformations of global nature. And wind parks to the extent of transforming, capturing, dissipating, deriving, diverting, braking slowing down 1/1,200 or even 10/1,200 of the NATURAL patterns of the air in the whole planet, won’t very likely go without consequences.
There have been numerous posts here dismissing the effects of 1 or 5 or whatever TW of wind installed power, on the basis that our human constructions are already transforming, capturing, dissipating, deriving, diverting, braking slowing down the winds of the planet without apparent consequences.
They were usually being quite groundless for lack of documentation.
It is not the same friction that of a keel, designed to have minimum friction, than the propeller of ship or vessel, designed to have the maximum friction to propel.
As it is not the same friction the rotating blades of a windmill than a round glass covered skyscraper in Florida designed to resist hurricanes with force 5.
The arguments on frcitions on human constructions are groundless because nobody, to the best of my knowledge, has calculated how much anthropogenic friction is causing a five stories apartment block line, brick made and oriented to the dominant winds 8or opposed to them or in a given angle) in the place, or the friction of the shanty houses with corrugated roofs in Rio de Janeiro slopes. It is not clear how much friction changes in a suburb filled with detached houses in Oregon, named “Evergreen Oaks” and if it is more friction or less than the previous existing oak forests, destroyed to build the condominium (Howard Kunstler. The End of suburbia. Not literal, but stating that suburbias take the name of the natural places they are to destroy)
In any case, there must be an obvious diversion, friction, transformation of the natural flows of wind caused by the anthropogenic activities or human constructions, which has left our world as it is today: a lot of deforestation –Who said that deforestation has decreased friction only a little bit? Half of the forests of the world have gone already. John Perlin: A Forest Journey. The Role of wood in the Development of civilization-, huge erosions, desertification, growing footprint consequences, etc..
But dismissing the additional effect of several TW of wind power, is like pouring 100,000 tons of shit in a dump and as we do not observe direct or immediate consequences, conclude that we can freely pour another 100,000 or 100 million tons more. Who know how much?, but it does not matter. We do not know how filled is the glass, but always anticipate that our drop will never burst out.
That is the message for those who want to listen. Precaution principle and understand that the world is limited and we are reaching the limits in many different ways.
There is a difference in the application of the precautionary principle to wind power and the burning of fossil fuels. Any effects on wind patterns last only as long as the obstructions remain, and any new powerplant (solar, fission, fusion, unicorn farts, whatever) can replace wind farms. The effect of burning coal or gas lasts for a thousand or more years after the act.
I haven't heard of unicorn fart power before. How does that compare to dilithium crystals?
I believe one is a Cochrane transform of the other.
What's amazing is your breezy dismissal of obviously viable Desertec, on the basis of such "insurmountable" obstacles. Really? Why are these submarine cables any greater a problem than the ones going from Spain to Majorca? Sweden to Denmark? The only issue of cable size is trying to get ENOUGH generation started initially to supply an economic amount to even one HVDC cable. Seriously, HVDC is not the limiting factor. And solar thermal in good insolation areas needs only the economies of scale involved in a series of projects totaling 3 to 8 GW in order to become more economical than Natural Gas. See Sargent & Lundy Engineering's independent (and very thorough) analysis. "Assessment of Parabolic Trough and Power Tower Solar Technology Cost and Performance Forecasts - Sargent & Lundy LLC Consulting Group - Chicago, Illinois"
http://www.nrel.gov/csp/pdfs/34440.pdf
Your whole rant is full of similarly unsupported nonsense.
Are you serious? Any data apart from a biased article on how good the parabolic through solar plants are going?
Here there is some data from a country which has plenty of parabolic trough plants and is exporting this technology to the US and installing plants there:
2010. Solar Thermal energy in Spain (best insolated country in Europe):
Installed base (grid connected or feed-in mode): 532 MW
Energy sold: 692 GWh
Operative installations: 13
(Data: Official sources: Comision Nacional de Energía CNE: http://www.cne.es/cne/Publicaciones?id_nodo=143&accion=1&soloUltimo=si&s...)
Some other data from the industry (Prototermosolar, Spanish Association of the Thermoelectric Solar Association) in July 2011
Operative: 19
Under construction: 20
In Promotion: 22
Totalling 2,535 MW
Real world Efficiency –Load Factor-(not marketing paperwork or brochures) of the operative ones as per the official, ministerial, independent sources: 14.8%
They are allowed to account as “renewable” up to 15% of the back up gas fired power plants attached up to 15% of the production to give stability to the plants and to avoid the melting salt deposits used as an energy buffer for clouds and nights (usually 3 to 4 hours autonomy) to solidify in the nights.
Some solar thermal plants have been denied permits in Spain because they demand water flows of 6 litres/second in very good insolated areas, but where there is already a battle for water scarcity and Spain is the 4th. country in the world desalinating water. If this water has to be used to refrigerate the system and clean the mirrors and is in fight with the agricultural production, already desperately asking for fresh water, then we are making a bread like a Holy Form (Spanish saying) or killing flies with guns.
In Morocco, the problem is similar or even worst. Also several plants have been denied. In other places, multinationals simply take rights to the water and deprive agriculture of basic supplies in favor of modernity.
It is not as simple as your own rant that is going to be “more economic than gas” (when we will see in an energy forum people talking about energy EROEI, net energy, efficiencies and so, instead of comparing apples of economy with pears of energy?
Combined cycle gas fired plants in Spain are doing a great, great favor to the renewables. They grew from zero in 2003 to 25.2 GW of installed power in 2010. They were originally designed and built to reduce the CO2 emissions in a coal intensive country to comply with Kyoto Protocols. The plans were to be operative at least 5,000 hours/year. (57% load factor). Due to the priority given by law to the intermitent renewables to enter into the grid, the combined cycle gas fired plans were acting as swing producer. The more they injected, the less they could work. Today, they are working with 25% load factor (25.2 GW producing 64.9 GWh/year). Promoters are blaming and claiming to the renewables, because they are very much in the red, but they cannot apply to chapter 11, because the government does not allow, as they need to be installed as back up for renewables, just in case. Is this the type of economic cost efficiency you are comparing when confronting gas with renewables? Has anybody entered into an EROEI equation o renewables the extra costs of these idle combined cycle gas fired power plants, to make an electrical network feasible, plants that, by the way, degrade much faster than normal because forced to frequent switch on and offs, for which they are not designed?.
I see what you did there.
The source you cite shows solar thermal installed base at the end of 2010 was 532 MW, but at the end of 2009 it was only 232 MW.
One will indeed reach a false answer of 14.8%, clearly much lower than the actual capacity factor, by using the 692 GWh generation DURING the year and the 532 MW installed base at the END of the year as one's numeric inputs.
For any form of generation with very slow annual growth the error in this approach would be small, but in this case the installed capacity more than doubled during the year so the error is very large.
Good catch. Using the 232 MW nameplate capacity, the 'actual' capacity ends up being 34%. Hence, the true answer is somewhere in between, only available by determining when each new system became fully operational in 2010.
You are very right. Sorry for the error. I am trying to get data from CNE of previous reports, which have been modified later and I still do not know if they first did not account the percentage of backup gas allowed to be considered as 'renewable' where the efficiencies were significantly lower and in the last reports they include it as 'renewable'. I have made an official question to CNE onn the subject, but their previous reports disappeared from the web
Solar thermal is close to dead anyway since (waterless) PV has simply gotten too cheap by now.
Even one of the biggest solar thermal player has meanwhile switched from its core technology/business to PV:
http://www.mydesert.com/article/20110819/BUSINESS/110819002/Solar-Millen...
http://www.bloomberg.com/news/2011-08-18/solar-millennium-says-technolog...
Silicon PV-Modules are available from $1.10 /W (and prices are still falling)
and thinfilm PV-Modules are available from $0.85 /W (and prices are still falling):
http://pvinsights.com/
Needless to say that Morocco could produce enough power with (waterless) wind farms to essentially power entire Europe anyway: http://www.riaed.net/IMG/pdf/L_energie_eolienne_au_Maroc.pdf
(Not that there's any need for this, given the fact that Europe itself has enough renewable resources and efficiency potential anyway).
And as far as your Spanish combined-cycle-gas-power-plants-capacity-factor-concerns and Kyoto protocols are concerned.
Spain can still reduce coal power and solve both problems: https://demanda.ree.es/generacion_acumulada.html
Besides, combined cycle power plants have low capital costs and short construction times and can still be run profitable even at low capacity factors (as opposed to new nuclear for instance).
The German combined cycle gas power plants have a capacity factor of 36% and are primarily needed for balancing demand (unfortunately people consume up to 3 times more power during day time than at night):
http://www.bdew.de/internet.nsf/id/42E50819A5083E88C1257877002D00AB/$file/Energiemarkt%20Deutschland%202010.pdf
Where can I buy some of that $0.85 PV? I note that World's biggest solar power farm opens By: thinkSPAIN If you do enough base studying to get around the confused authors muddling terminology, you find that a 20 MW Solar PV farm is costing Euro150 millions, about $200 million, or $10.00 per watt.
Len,
I read teh article as 30MW: " capable of generating 30 million kilowatts an hour. "
If we used purchasing power parity, I'd say that's about $170M. Still more expensive than we'd expect.
Wikipedia says it's 20MW, but that it opened 4 years ago. I think it's age helps to account for most of the difference...
We are in the year 2011 and not 2007!
PV-module prices have been in free fall since!
Here's thinfilm supplier where module prices start at $0.88/W:
http://www.alibaba.com/product-gs/454020864/amorphous_solar_panels_Thin_...
Here's a crystalline supplier who sells modules for €0.84/W:
http://www.alibaba.com/product-gs/434755672/Poly_Crystalline_Silicon_Pho...
Here's a German offer for a small complete PV-System with crystalline modules for €1199/kW including 10 year warranty:
http://www.gehrlicher.com/de/home/wholesale/summer-sale/#.TmnFDUfzj2A
And if you are really stingy you can also just buy solar laminates with crystalline cells for $0.50/W per pallet:
http://www.sunelec.com/solar-laminate-c-47.html
As I said: Solar thermal is close to dead...
I would suggest not being so fast in extracting conclusions about solar PV energy based exclusively on present market prices.
Prices were in the range of 2 Euros/Wp and when the demand raised in Spain so abruptly, went up overnight to 4 Euros/Wp when the presurre for installing before September 2008 mounted. Then, when the factories collapsed, when the government admitted they could not go forever with more subsidized installations and this took many factories, without having amortized even 10% of the expensive and sophisticated manufacturing, assembling and testing recently acquired machinery, the clearance sales dominated the market and prices went down to 1.2 Euros/Wp.
Further hints that the growth is slowing down not only in Spain, but also in Germany and other subsidizing pioneers, has brought prices to the levels you mention.
Another important factor to push prices down is the impressive last two years relocation and outsourcings of manufacturing and assembly (and even research) plants from Europe and US to China, which has put to its knees to factories like Evergreen, Solaria and many others in Spain and everywhere in the developed countries. China plays policies which have to do very little with prices related to costs. Their strategic aims focus more on market share capture and control at any expense, than in short term or annual term benefits and they may well be selling below costs, even with their ultra low cost labor and recent moves to capture rare earth deposits worldwide, for that reason.
And finally, some sensitivity analysis I have made with my data base has coincided with a big, big solar PV EPC firm with which I have closely worked in 2010, in the sense that if you think in solar PV systems, instead in modules and include all the extended boundaries for energy and economic embodied costs, the cost of modules represent 1/3 of the total turnkey project in feed-in form. So, the lowering down of module prices will have an asymptotic minimum that for instance makes a breakeven point in thin film with respect to crystaline, when prices of a turnkey project reach as low as 2.5 Euros/wp. This, for the need of more mechanical and electrical infrastructure, more trenching, ducts, concrete, etc. on per MW basis than with crystalline.
If modules could go to zero one day, the EROEI and the economics costs of the turnkey projects will reach a minimum, from which they will not go down any more, that will have nothing to do with the cell technology improvements. Not to mention, on the impact of the turnkey projects if all other extended boundary costs, like taxes (always increasing taxes; ask Spanish promoters), prices of lands, of the rights of ways for evacuation lines, of the evacuation lines themselves, the concrete, steel, aluminum, copper, trenching, cabling, nuts, bolts, tempered glass, operation and maintenance, with their pickups, cranes trucks, etc., administration expenses, premature and unexpected amortization of manufacturing equipment, etc, etc., etc. which are inherently very dependent on fossil fuel costs, increase. Or does anybody believe that a solar photovoltaic or solar thermal powered plant is only cells, and modules and perhaps an inverter or parabolic mirrors, synthetic oil flowing through a molten salt deposit and a turbine?
All I'm saying is that solar thermal is close to dead because PV modules are meanwhile close to the costs of mirrors.
PV manufacturers produce over 20 GW this year. They cannot afford to produce millions of modules below production costs. (This may be an option for VW and its Bugatti Veyron but definitely not for a mass product).
Germany and Spain may install less PV in the future but other countries such as China certainly aren't:
http://uk.reuters.com/article/2011/05/06/china-solar-idUKL3E7G5546201105...
Anyone said
And as far as your Spanish combined-cycle-gas-power-plants-capacity-factor-concerns and Kyoto protocols are concerned.
Spain can still reduce coal power and solve both problems:
Oh, very smart. Apparently, the Spanish industry and government had not noticed such a clever idea. Perhaps you could convince them, as they are struggling since years to see who in hell is going to pay for dismantling coal fired power plants and for the increasingly idle combined cycle gas fired power plants and for the increasingly switched off wind parks. Decades debating who will in the hell pay for the pump up hydro installations to back up renewables and they did not notice how simple was the solution.
Coal being the only independent source of energy, even dirty, is one third of the coal that Spain consumes from its own mines (horrible brown lignite), apart from wind, solar and hydro. Despite of having 17% of the total national electric demand from wind and already 3% from solar PV+thermal and a variable amount from hydro, depending on the seasonal year, of 7 to 20% of the electricity, still this makes Spain a 90% dependent country from foreign PRIMARY ENERGY sources, including nuclear, which I consider (contrary to the Ministry of Industry) to be an imported source of energy, because even it makes a 20-22% of the national electricity demand, we are not producing a single gram of uranium inside the country, we have no enrichment factories and we lack essential technologies that come from abroad.
as they are struggling since years to see who in hell is going to pay for dismantling coal fired power plants
Of course, people in Spain could also just buy overpriced houses (several order of magnitudes more expensive than dismantling a coal fire plant) from each other and not work at all (unemployed rate is already at 20% anyway, so what).
As long as the housing prices go up, there's really nothing to be worried about (and bankers will assure you that this is always the case)...
Decades debating who will in the hell pay for the pump up hydro installations to back up renewables
So, you are basically saying Spain is currently working fine with its renewable penetration of well over 20% without even building up pumped storage.
Btw, Switzerland (5 times smaller than Spain) is currently adding 4 GW pumped hydro mostly to pump French nuclear power at night and on weekends and not to store renewable power but simply because its good for business.
Also, Switzerland without any serious renewable program is trading more electricity (yes more electricity) than the entire country consumes: http://www.bfe.admin.ch/energie/00588/00589/00644/index.html?lang=de&msg... (and just by trading electricty it earns over $1.5 billion per year.) And Swissgrid says it's not enough - 1000 km of more electricity grid is needed: http://www.drs.ch/www/de/drs/nachrichten/schweiz/272052.swissgrid-forder...
Spain could also consider building up its electricity connections with France, Portugal and Morocco (of course it doesn't have to be as much as (new-renewable-free) Switzerland).
Thanks again, anyone.
I suggest that you candidate as consultant for the Spanish authorities and electric operators, if it is so easy. Housing prices going up was a thing of the past. Perhaps banksters offering credits for 120% of the market value could help in solving the problem by buying back now instead of sending the unpaid mortgages to auction and take the houses for less than 50% of what they themselves had assessed as “market value”, leaving the former owner in the street and still with a debt to pay. Liquidating the mortgage by giving back the house to the bank, only works, perhaps in the Us, but in Spain the dispossessed still have to pay for the different between the auctioned price and the contracted price. Slaves for banks for the next 25 or 50 years. Unemployment is not only 20% at national level; it is 45% for youth.
What the Swiss do with pump up to help the French with their nuclear power, if they are desperately to find stabilization in the night valleys with such a heavy base load, is for the Swiss and for the French. Sure they are getting paid and well paid. The 4 GW is a little bit more than the pump up capacity installed in Spain, basically for nuclear night valley stabilization, not to help renewables. They also paid for that. But nobody wants to pay (or include in their budget or in the energy investments) for pump up for renewables. As you see it so easy, the Spaniards would very much appreciate your ideas and suggestions.
As for the connections with Morocco, they are being upgraded, but Morocco consumes 20 TWh/year and already exchanges (basically imports from Spain) already 4 TWh. If the Desertec dreams or North African generations for European consumptions develop, we shall see. But now it is not much Spain can do there.
With Portugal, Spain has already 3TWh/year of exchanges (also mainly exports from Spain). CNE has already integrated with this Portuguese counterpart and has a higher throughput for exchanges.
And with France, ask the French, why they are reluctant to increase the interconnectivity being requested from the Spanish side for more than one decade. And it is not because the orography difficulties or environment issues in the Pyrenees. Two can never agree if one is not interested. You can ask any official in the Spanish ministry or in REE to see what is happening in that border.
That is why I mentioned in other post the difficulties for North African projects to sell solar PV or wind energy to Europe, specially to Central Europe with thousands of Km. of rights of ways through several nations with their own open or vested interests.
With Portugal, Spain has already 3TWh/year of exchanges (also mainly exports from Spain)
Obviously Spain could do much better, if a country like Switzerland which consumes 5 times less electricity than Spain can trade over 60 TWh/year with all neighboring countries.
You do realize I hope:
a) Natural gas fired electricity generation even from locally produced conventional wells is in fact not likely any better for the environment than coal.
Switching from coal to natural gas would do little for global climate, study indicates
b) Even worse to use imported LNG from countries with poor regulation on methane leaks during exploration and the picture gets worse. Add in the up to 50% CO2 which is commonly produced from natural gas wells during production, separated and exhausted to the atmosphere near the wellhead. (See Japanese documentation of their wells offshore in Indonesia).
c) Worse yet, consider the high energy usage, and therefore high up front GHG emissions, of drilling and fracking operations to produce tight gas, now the only remaining "great hope" for natural gas outside of Russia, and soon enough there.
You Natural Gas investors give me a pain. Call clearly accurate studies from knowledgeable indepentent engineering firms "biased" with no statement of justification. Complain like crazy if solar doesn't include every minute overhead input to its production figures, but do your own GHG emissions calculations using only the carbon content of stoic combustion in pure oxygen to calculate your own, ignoring fuel use in exploration, at the wellhead separation, purification and "sweetener" plants, pipeline compressor emissions to compress and transport the gas often thousands of kilometers, and added compressors to put off-season production into and out of storage caverns, and obviously constant leakages (GIVE ME A CREDIBLE NUMBER with reference) of methane to atmosphere at every step in the processes. Nuts.
Len,
That study is kind of odd, as it counts reductions in sulfates and other aerosols as a negative!
With this kind of analysis, any alternative is going to look bad, because it reduces coal's particulate production!
I'd like to see a head-to-head comparison of alternatives: e.g., nat gas vs nuclear, or NG vs wind.
Another factor to consider is that climate change is reducing the total amount of wind on a global scale, and making wind more extreme and less predictable. The wind surveys we use for siting wind farms today will be obsolete in the future. The (relatively) steady, moderate, and predictable winds that are ideal for wind power generation will not be that way in the future.
Wind is a nicer solution that coal, oil, or nuclear, but wind by itself will be not enough.
The reductions are expected to be small over the next few decades. We can worry about other things.
When/if wind speeds to drop a bit we can add longer blades or switch to more efficient turbines.
Wind alone could be enough. But a mixture of inputs works better. The more varied the inputs, the lower the overall variability which means less storage/backup would be needed.
Am I missing something or are the authors arguing that sailboat races for example would decrease wind kinetic energy to a measurable effect if the boats were too closely spaced due to wind dissipation? Hmm... That doesnt smell right to me. The layer of wind on the surface is small relative to the thickness of the atmosphere.
Also generally when you multiply several factors together you need to propagate your errors. Then we can talk about the final figure and its significance. There is no bounding of these figures and error propagation or degree of certainty. It makes this exercise hard to follow without confidence levels.
In boat racing terms when another boat crosses upwind of you it's known as stealing your wind, and the effect can be felt over a surprising distance. The turbulence caused lasts even longer, so even following in the lee wake can be felt.
The vortex shedding from aircraft wings has a similar property. That's why air traffic control has to organise the order that planes take off based on size. A Cessna would have to wait for up to 5 minutes to take off after a 747 to allow time for the vortex to dissipate/move downwind.
Wind turbines want nice smooth air flow over their slow moving blades, so they suffer noticeably when the flow is disturbed. A couple of kilometres downwind from a big farm may be back to the original airspeed, but if it's not back to a laminar flow then any turbines positioned there will be less efficient.
A similar issue is putting a limit to turbine size. The stress range on the blade tips from high speed laminar flow wind at near 200 meters compared to slower and more chaotic flow near ground level is close to the structural limits. We now have the technology to actually manufacture turbines that are bigger, but they'll just shake themselves apart.
... unless the hubs are placed higher to put the blades above the worst turbulence.
... or unless active control is used to reduce stresses (as has been done on airliners).
Actually, what you describe does indeed happen in sailboat racing. The upwind boat positions itself to put the downwind boat in "dirty" air, and the downwind boat actively tries to avoid being put in that position. It's part of the strategy of racing.
TOO LATE - Good reply above
I think that the fact which confuses most of the readers is that the effect of dissipation in the wind farms could be so important to undermine energy harvesting at other, even distant, locations. This is not intuitive as it has never happened, but that does not mean that I couldn't happen if we go ahead and increase the scale of wind farms beyond a tipping point. Looking at the wake of a present wind farm is not the point because there is still a large pool of wind energy surrounding that will flood the area; the problem is when a number large enough of such farms are distributed around the world. I think that we all agree that for a number large enough of wind farms a global-scale effect of wind weakening should be observed even if the farms are rather distant from each other, so the point at the end is trying to guess how large is this number or, equivalently, how much wind energy can be dissipated until the effect precludes further harvesting. At the end, that calculation should proceed much in the way De Castro et al have done, just trying to better fit the different ratios involved in the product and, of course, the available energy budget. So at the end the criticism is not as much about the methodology as about the experimental parameters (f1, f2, etc). As none of us know those values with accuracy we should first be cautious in criticizing this work, a work that anyway opens an interesting new way to explore the problem of the total wind potential of Earth. I insist in using GCM coupled with simulated wind farms to observe the effect. On the other hand, I know some nasty effects can arrive when too much wind energy is harvested: I'm presently participating in a European project that will study the impact of off-shore wind farms on Marine Protected Areas, particularly as upwelling and resuspension on nutrients in sea can be inhibited by the loss of wind drag at sea surface.
Besides, I want to insist that topographic elements, if they have too much drag (as mountain ranges or thick forests) are in fact almost solid with regards to wind circulation and the flow just surrounds them, displacing up the atmospheric bottom boundary layer. In fact, we have not many real examples in the Earth of a structure not too dense but with large enough drag, producing an effect comparable to wind farms.
Concerning the paper, the complaint about "it is beyond a paywall" is a bit silly. Have you thought about contacting Carlos de Castro (easy to find e-mail, you know, he works at Universidad de Valladolid, Spain) and requesting an electronic copy from him (that he has the right to distribute under personal requests)? In fact, I got my copy in this way.
Regards.
Thanks AMT.
My e-mail is: carcas@sid.eup.uva.es (please the criticism in the oildrum)
Regards.
I believe we are far from harvesting wind and solar in the most efficient ways,I mean were basically in the infancy stages now.Surly wind turbines and solar panels are but a beginning and not the status quota.We need to access wind and sun up where its many times more powerful.We will continue to advance all renewables and in the future what we have today will be obsolete technology.If we had started when we should have we wouldn't be having this discussion on weather or not wind can power our needs.I guess we have to start somewhere huh.
The real question isn't can we but rather is there time left to do so.
Reading the reactions here, it seems that many people don't realize how much electric energy is still being wasted in places like the US, and are also forgetting that amount availabe from hydropower, which continues to grow.
82m Germans use 640TWH, while 310m Americans use 4400TWH., implying waste in the US of roughly 2000 TWH.
There is 3300TWH of hydro power worldwide.
We don't need wind and solar to replace 17000TWH. We need quite a bit less than that.
Good points. Cut the most wasteful users (mostly US) rate of use by a quarter, cut European (and others at that level) rates of use by half, and you still have a quite comfortable lifestyle that is well within the range of what renewables we have now plus what could reasonably be geared up in the next couple decades.
The one thing I agree with about the article is the implication that we can't just expect to grow forever with renewables. The earth does have limits, and we need to start living well within them...I would say before it's too late, but it is looking like it may be too late already.
It says a bit more than just that renewables can't enable indefinite exponential growth. To anyone mathematically literate that is a tautology. He places a firm (and rather low) cap on the resource, that would seem to be lower than some national energy plans in place today. That later fact, if his analysis holds up, is important.
LEDs are becoming quite affordable. Macy's is replacing 1 million halogen bulbs with LEDs and will save $1 billion in ten years. LEDs last 7x or more longer than halogens which means less bulb costs and maintenance costs.
And a lot less electricity.
Expect all other retailers and commercial buildings to follow suit. That will happen just as fast as manufacturers can crank out the bulbs.
Residences will tag long.
We'll be saving electricity and energy making and distributing billions of bulbs. These are major energy savings which will cause no decrease in lifestyle.
Hello Bob, thanks for the news about Macy's. Truly saving energy is much easier than trying to generate more. I read online that Macy's was seeing a one year payback on the new bulbs. Your 1 billion dollar savings seems too high ($1,000 per bulb), but whatever it is it will be substantial over the 10 year life of the LED.
I hope to see more comercial establishments in malls use the more efficient LEDs.
$1000 per bulb? That's $100/bulb/year, power and maintenance.
At 2500 hrs lifespan and 16 hrs/day use, the halogen bulb would have to be replaced 23 times over 10 years. Estimating $5 for bulb and labor, that's $115. 57600 hours times 100 watts is 5760 kWh, or $576 at $.10/kWh (more at NYC or Japanese rates). That's pushing $700 per bulb right there, without including savings from lower A/C costs and assuming they're actually turned off at night. I'd believe $1000/bulb savings from LEDs.
According to a web site Macy's maintenance people average over $40k per year. Add at least 25% to that for employer overhead. Changing out a bulb might average 15 minutes for the guy to get in place and do the job? Going to be higher than $5 for bulb and labor.
That's assuming that the bulb can be changed with a 'stick'. If it takes a ladder safety regs might require a second employee. (Pure guess.)
This would be a Preventive Maintenance kind of program, in which all of the bulbs are changed at once. That's far more efficient and cheaper.
With halogen bulbs do you think they would change out an entire floor as soon as the first one failed? In places where I've worked it's been more the case of submitting a work order and having maintenance showing up with their ladder.
Perhaps things are done differently in large retail.
Large, well managed organizations replace their bulbs all at once, at a point in the wear cycle at which only a small % of the bulbs from the last cycle have burned out. This is part of a proper Preventive Maintenance program.
Ad hoc replacement is annoying for the people on the floor who need the light, and expensive: the labor savings of PM is much greater than the minor cost of premature replacement.
Also, the cost of hiring a cherry picker/access platform needs to be taken into account when dealing with large commercial premises, a ladder just won't cut it. Plus stock and displays may need to be moved for access. If you are going to do all that you may as well do a whole bunch of lights.
NAOM
Not trying to be argumentative, but all this does not sound like $5 per bulb change.
That's why you do a whole bunch at a time. You spread the cost over a large number of bulbs. You also need to remember that many will still be in step ladder range too and, if done at the same time, come into the costing. Remember that these stores need to do all this to change bulbs anyway so, by cutting the number of changes, there can be considerable savings.
NAOM
It would depend on the quality of management, and labor costs. The equipment cost would be trivial - they'd have an in-house self-operated scissors-lift.
These days I doubt Macy's is still using union electricians to change bulbs, so the all-in labor cost would probably be no more than $20/hour. I would expect they could do change at least 15 bulbs per hour, for a cost per bulb of about $1.33/bulb.
Hi Nick,
Group re-lamping is common practice in the case of fluorescent lighting systems where rated lamp life ranges anywhere from 20,000 hours for older T12 systems to now as high as 55,000 hours (Osram Sylvania's Octron 800XP/XLT8s). Typically, this occurs at 80 per cent of rated life. Thus, a retail store that operates 4,000 hours per year, say, might be group re-lamped once every eight years to ten years.
Halogens, on the other hand, are spot re-lamped due to their shorter lifespans and because they're generally used to highlight displays that must always look their best. Halogen lamp life falls between 2,500 and 4,200 hours. Again, assuming 4,000 hours operation per year, the halogen lamps in this same store would require re-lamping every six to ten months, a prohibitively costly proposition both in terms of materials and labour. Secondly, at 80 per cent rated life, 20 per cent of the lamps will have already failed and that number of failed lamps would never be permitted in the retail trade.
Cheers,
Paul
Interesting. So switching to LEDs would allow operations to switch from spot replacement to group replacement.
That makes it a lot less expensive when one includes the cost of moving displays.
Hi Bob,
I suspect spot re-lamping will remain the norm. As you know, LED lamps are considerably more costly than their linear fluorescent and halogen counterparts. For example, a Philips 800 series 17-watt EnduraLED PAR38 will set you back some $65.00 whereas a halogen-IR PAR38 is perhaps one-tenth that and an 800 series T8 is one-tenth that again. Given this fairly steep premium, there will be a push to extract as much useful service from each lamp as possible. If you were to group re-lamp at 80 per cent of rated life, you're potentially forfeiting up to two years of additional service, or more in the case of lamps that were added after the fact to replace those that failed prematurely.
With respect to the labour component, larger department stores will have a maintenance engineer on staff or they'll employ a third-party such as Sylvania Lighting Services to manage this on their behalf. At the smaller mall locations which likely account for the bulk of the sockets, the store manager and his or her staff will likely perform this task and so the labour cost is effectively nil.
Cheers,
Paul
It looks like LEDs are rapidly dropping in price.
60 watt equivalent for $15. That's a 50% drop from earlier this year.
http://www.greentechmedia.com/articles/read/lighting-sciences-15-led-bul...
Overall we should see a noticeable drop in electricity used for lighting.
LEDs are dropping in price, but the quality can be a bit hit and miss and is true of most things in life, it's largely a case of you get what you pay for. And, no question, you pay a premium for Philips products but, in return, you're assured of good performance, long life, a solid warranty and a firm commitment to honour it.
That said, Philips' L-Prize 60-watt replacement generates 910 lumens, consumes 9.7-watts, has a CRI of 93 and its lumen maintenance at 25,000 hours is a whopping 99.3 per cent and, if what we read is true, it will sell for $22.00 when it goes on sale next year, dropping to $15.00 in year two and then $8.00 by year three. It doesn't get much better than this, although things are advancing so rapidly who knows what to expect three years hence.
Cheers,
Paul
This is a fascinating example of economies of scale.
On the one hand, small retail locations don't have the management time to think about such things, and don't have enough staff to easily get clear savings from labor or energy savings on small items, like lighting.
On the other hand, even for larger organizations lighting labor and energy costs aren't large enough to attract the time to figure out that that labor savings are worth achieving even if you can't directly lay someone off to capture clear cost savings! After all, those retail managers and maintenance personnel could be busy doing something useful, instead of doing one-off relamping.
------------------------------------
I'm struck by the very large variance in bulb life. That appears to be very low manufacturing quality assurance. What happened to 6-sigma quality??
You lost me with that post. The discussion started with Macy's switching out a million halogens with a million LEDs and saving a hundred million dollars a year. Macy's figured out that they can save a bucket of money while 'laying no one off'.
That news is spreading and other retailers are almost certain to follow suit. Competition is fierce in retail.
The news will spread down to the small store level. Employees move around, stores get advertising literature and trade literature, people visit the web and talk to friends. Utility companies seeking to lower their peak demand problems will run information programs.
Changes will happen quickly in those small chain stores. There are something like 30x as many Subways as Macy's. Subway owners/managers will get the word from on high.
Finally, as large users switch away from halogens regular buyers are going to notice that shelf space for halogens is shrinking and the stock getting dusty. Only the real-slow-on-the-uptake are going to be unaware in a couple of years.
Fred running the used TV shop is going to decide it's worth a couple extra bucks to buy a LED next time and avoid dragging out his ladder once or twice a year to change the halogen that spotlights his 'deal of the week'.
I agree.
I was simply talking about Preventive Maintenance, and how I suspect that most organizations with a decent number of lights would save enough labor by relamping all at once that it would be worth their while.
Business, even small business, is much more aware of energy costs then residential consumers, so they'll switch reasonably quickly.
Still, it's often surprising how slowly even large organizations move to new things - people have large investments in training and expertise from daily practice (which can take 10 years to really fine-tune), and don't switch to new things lightly.
It's not a quality issue as such; rather, these are very different technologies and their service lives reflect this. A standard tungsten-filament lamp has a rated life of 750 to 1,000 hours whereas the nominal life of a tungsten-halogen is generally three to four times that. A good quality ceramic metal halide (another popular choice among high end retailers) lasts anywhere from 12,000 to 20,000 hours and linear fluorescents as we noted are fast approaching 50,000 hours and beyond. Although it's technically possible to manufacture an incandescent or halogen lamp that lasts 20,000 or 40,000 hours, the trade-off is greatly reduced lumen output -- ever notice how long-life incandescents are notably dimmer than their standard counterparts?
Cheers,
Paul
I'm not thinking of the difference in service-life between different technologies. I'm thinking of the variance in service-life within a single tech as shown in your chart. Remember what you said:
Secondly, at 80 per cent rated life, 20 per cent of the lamps will have already failed and that number of failed lamps would never be permitted in the retail trade.
That seems way too high.
Sorry, my mistake. Rated lamp life is based on the point at which 50 per cent of the lamps in a test group have failed and 50 per cent remain operational. Some will die early on for whatever reason whereas others with solider past their demarcation, but the mortality curve for halogens pretty much follows what's shown above (the shape of this curve does vary by lamp type). As for the whys and wherefores, I'm afraid you'll have to ask someone more knowledgeable. My guess is that most consumers accept, perhaps begrudgingly, that this is the way it is, and that if you want 100 per cent of your fixtures to be operational 100 per cent of the time, or something close to this, you'll have to haul out the step ladder more frequently than you may wish.
Cheers,
Paul
Sure.
I'm just thinking that the slope of the curve should be much higher, with a much smaller % having failed at 80% of rated live.
Manufacturing prides itself on it's improvements in such measures in recent years through aggressive use of statistical QA. Six Sigma and all that.
Just wondering...
I would guessed that the overall % of halogen lighting in industrial/commercial buildings is pretty small.
LEDs are likely to create some significant savings at the residential level where 11% of all electricity goes to lighting. I doubt too high a percentage of bulbs have been switched to CFLs, so the LEDs are going to be making big differences as we phase out Incandescents and halogens.
Love the low hanging fruit of efficiency. It helps to clear a hurdle if someone lowers it for you....
I'm trying them at home. Oddly, they have a roughly 1.5 second delay on lighting up, something that LED's didn't traditionally do.
CFL or LED having that delay? The CFLs have a soft start built into the circuit to cut down on current surge when they start up. Less current rushing through the capacitors etc leads to a longer life. The LEDs will have some sort of switched mode power supply in them so I would expect a soft start there to cut the current surge through the components. Also, with high powered LEDs, a slow ramp of current would cut down on thermal shock, again, beneficial to life.
NAOM
I'd say it's closer to half a second. Just changed all my bulbs over. Though maybe it depends on the make you use.
Because the previous occupant had used 40w bulbs to save a little energy over the 60w ones, not only have I reduced my power consumption, but have now got brighter rooms.
Now I just need to avoid Jevons paradox and it's a win, win, win situation.
Sorry, but was that for CFL or LED. I use CFL and would agree with the 1/2 second but I have noticed they do vary with brand. There is one that I use rarely, an old one, that takes some time to ramp up.
NAOM
Actually, you have the classic case of Jevon's in modern times: light levels rise, while power consumption falls even faster.
I've found that some LEDs create huge amounts of radio-frequency interference up through the FM broadcast band. Very irritating. It should have been eliminated with proper design.
Halogen still dominates the retail and hospitality sectors. There are an estimated 550 million halogen lamps in service in the United States alone.
Cheers,
Paul
Macy's is roughly halfway through switching out their 1 million halogens for LEDs.
They've stated an expected savings of $1 billion over ten years, $100 million per year.
Look for that 550 million halogen number to start rapidly falling. 549 X $100 million is serious money.
And thanks for that 550 million halogen number. If we assume that each halogen pulls 50 watts and it is getting replaced with a 16 watt LED then we've got a 68%/32 watt electricity savings per bulb.
Wonder how many hours per day/year the average retail and hospitality bulb burns? Eighteen? Close to 365 days a year? That would be 6,570 hours of saving 32 watts per bulb. 210kWh per bulb. 115,500 GWh per year.
3,949,694 GWh total US electricity generation in 2009. A 3% electricity savings in retail and hospitality alone. Lots of Incandescents still left in residences which use 11% of their electricity for lighting, the saving is going to be higher there.
(Feel free to fix my math. Half coffee and rusty math skills on this side of keyboard.)
I imagine many of those halogens are in residences.
It could be sometime before we start to see a widespread move away from halogens. First costs are a major hurdle for many businesses both large and small even though the lifetime NPVs are extremely good. Others remain sceptical of the claimed life expectancy and are taking a more cautious wait and see approach. I run into this from time to time, which is rather surprising given that we use only quality products backed by a strong manufacturer's warranty (Philips) and Efficiency Nova Scotia will pay up to eighty per cent of the total cost (materials and labour) and the remaining portion can repaid over twenty-four months interest-free on their NSP account. Here we're practically giving away the lamps and installing them on their behalf and the response is "no thanks". I don't understand it and would be hard pressed to explain it, but it's happened to me more than once.
Cheers,
Paul
I would guess that businesses get approached with "can't fail" opportunities to make/save money all the time.
Once a Macy's or a few "Macy'ses" produces results skepticism should drop away. Let the word get out that your competition has a $100 million advantage that's letting them underprice you a penny or two and things will change.
--
Wonder how they would react were you to offer to give them a small test installation? Put LEDs in only part of one floor and summarize the replacement data for a couple of years? Give them no replacement LEDs or keep very tight control over theft so that it would be very clear as to the number of units switched. The electricity savings, you're already crunching those numbers.
I have a client that operates 1,000 stores across Canada under several banners. Initially, we started replacing their halogen PAR38s with Sylvania Powerballs (self ballasted ceramic metal halide lamps) and although these lamps are certified for recessed fixtures they soon began to overheat, randomly cycle on and off and die prematurely; the ones in the track heads which account for the bulk of the lamps installed thankfully work fine as the open back gimbals allow for good heat dissipation. Osram were (and I'm trying to put this in the kindest way possible) less than helpful. We subsequently switched to Philips' EnduraLED PAR38s and have been extremely pleased with the results, and the feedback at the store level has been universally positive.
So the question that remains is what to do with the Powerballs in the recessed fixtures. I've recommended that we swap them out for the Endura but my client wants to use the Philips equivalent of the Powerball which we know can handle the job. The cost of this Philips ceramic metal halide lamp and the EnduraLED after rebate are within a few pennies and so price is not an issue. There's also enough physical separation between the tracks and the recessed fixtures and the light they generate is so similar that you could easily use both lamp types in the same store without risking visual distraction.
The long and the short is that the client is not convinced that LEDs will live up to their promise. Although the EnduraLEDs have been good performers so far, they still consider LEDs to be an unproven technology and, in their words, "once bitten, twice shy". I've done everything humanly possible to assure them that LEDs are the way to go and Philips have been extremely supportive in this, but they're just not there yet.
Here's a copy of my most recent e-mail to their head office:
Again, no dice.
Cheers,
Paul
Looks to me as if you've done more than enough. It's his money and if this is the way he runs his business someone else will eat his lunch.
I really doubt many companies will be this hard-headed.
Part of resistance to change is Return on Time Invested. I'm often surprised how slowly even large organizations move to new things - people have large investments in training and expertise from daily practice (which can take 10 years to really fine-tune), and don't switch to new things lightly.
The world is 7000m and use 17000TWH, do the Germans waste 440TWh and the US 3800TWh?
I bet a lot of people but the African nations goes over that limit.
This calls for a diverse calculation. Has anybody done it?
1... Develop a world map of surface wind velocity squared.
2... Estimate surface coefficients of friction for major surface types, ocean, plains, mountains etc.
3... Calculate the time dependent wind force applied over the surface of the earth by wind.
4... Integrate force times wind velocity (power) over a year to get total wind energy per year.
All done. See for instance public ERA40 reanalysis at ECMWF (hey, I think you ought to have something similar in the United States ;) ) The European Environmental Agency has several reports about wind potential using those data. May I point that De Castro et al. have used those data also?
I don't understand why some people tend to assume that the obvious points have not been taken into account; sounds like arrogance..
I looked at it; I see no calculation like the one I described. It looks like they have the data to perform step 1. They have not performed step 1, 2, 3, or 4.
Did you actually find the calculation I described; provide a link.
Why the attitude AMT, did you miss my second sentence;
or just being rude?
The article is very interesting. One thing I rarely read about is the high cost of maintenance of the individual turbines. They are exposed to all sorts of stress, temperature change, shock, animal intrusion etc. On the old wind farms in the banning pass of California less than 50% of the turbines are operational. On the newer farms there is still about 20% that are inop for reasons not known but I suspect many are maintenance issues. My point is this, if we build a farm and assume that it will produce 100% for life expectancy of say 20 years, experience has shown that won't happen without extremely high maintenance costs. Not trying to inply that its a great source of renewable energy but it is probably one of the most high maintenance of all the renewable's
Right- all WTs will eventually go the way of the Dodo and I, for one, believe this fact is not yet fully understood by the taxpayers. In a few years time Denmark and Germany will have to start rollover_programs - old WTs for new ones on a gigantic scheme - under the banner "Remove 1 old Watt for 2 new Watts". But at what cost?
Also as you note, whenever I see some WT farms on the telly for this or that reason ... quite a few of them stand still in a random 'maintenance' direction....
believe this fact is not yet fully understood by the taxpayers.
Wind turbines typically belong and were paid for by private investors (not taxpayers).
Needless to say that cars go to the Dodo much sooner and there are many more of those than wind turbines. Car owners have no problems getting their cars recycled. Why would wind farm owners have problems getting their wind turbines recycled (full with valuable copper and steel)?
quite a few of them stand still in a random 'maintenance' direction.
Again wind turbines typically belong to private investors. Why are you concerned about their losses?
Technology improves over time.
Some manufacturers are moving to direct drive turbines as gear trains are the most problematic parts of turbines.
Maintenance certainly is higher than for solar panels. But wind is still the cheapest form of renewable energy even when one includes maintenance.
What Bob said.A bit more information on the next techno step for wind:
GE Research Article,
http://tinyurl.com/3c5xwxv
This article needs to add consideration of the uncertainties in their estimates. They put a lot of focus on the number 1TW, but the uncertainty in this number is unknown and there is good reason to expect that it is so large that the number is of very little use at the moment. A thorough analysis has to include the range of reasonable estimates for each parameter and the resulting range of available wind power.
Agreed, that's what I was thinking throughout. (Missing error bars)
Perhaps it is in the original paper?
as a physicist this is the first reaction.
When I studied physics at first year we measured the sum of the internal angles of a triangle and it was different from 180 but compatible with it taking in to account the error bar.
Everything measurable should have an error bar.
Then when you have a formula with several components, each component adds its error with a formula know as "error propagation".
so you can start with an estimate of let's say 1200 in the form of [340-3600] or if you think that 1200 is for some unknown reason the most probable estimate in the form 1200 [+2400 - 860].
In the end you'll still have 1 TW as final result but at least you can have a good estimate of the attendibility of your estimation
There are a great many cascaded assumptions, which make the final range of this estimate, rather broad.
However there is, buried in this, a valid point, irrespective of HOW much possible TW there may be :
I've analysed this from a different direction, and you get broadly similar flag-falls. Even if we do assume kinetic averages are very large, the cyclic nature of wind mean the average power cannot go above some % of National Grid use.
That may be above 6%, but not by much. 2x, maybe 3x ? ie No one would claim 60%-Grid makes sense.
The other natural growth limit, is a practical and finance one.
At present growth rates, somewhere between 10-20 years, will see annual added GW, approach the 5-7-10 year addition-trend-in limit.
Suppose for an example, we decide 14% of Grid is a ceiling for wind, then adding more than say 1/5 to 1/10 of that in a single year, will give too much boom-bust, and so be less efficient. Build rates will sensibly taper off, 5-10 years ahead of the capacity limit.
This does give a logistical limit, (nothing to do with kinetic ceilings), and it is not really that far off, not when you look at that Build-rate effect.
This will give a year of Peak-Wind, in added-GW terms.
That may be above 6%, but not by much. 2x, maybe 3x ? ie No one would claim 60%-Grid makes sense
How did you get to this conclusion?
Spain, that is basically operating like an electric island in the Iberian peninsula, without almost interconnections with France, Portugal and Morocco, TODAY has 17% of penetration of the total national electric demand form wind energy. But it can handle with a good management of the grid (see http://www.ree.es/ingles/operacion/curvas_demanda.asp), peaks with over 50 percent of the consumption being covered with wind power.
Of course, this is handled because we have about 25 GW of backup combined cycle gas fired power plants, able to switch off and on, as per the wind variations, to help to keep the grid stable
I agree with _jg. I once did a plot of wind growth as a function of wind penetration for different countries listed here. (The penetration values are a bit approximate, as I was lazy by assuming the same capacity factor for all and by using only one year's total electricity production figure for each country.) I just updated the graph with 2010 figures, and I still find it quite striking. Even more so if one would discard the 19-21% figures that are all Denmark, a small country with extreme imports and exports of electricity.
The next few years will be very interesting, however, statistical samples for high penetrations are still very few. As you may notice, only five countries are significantly above 5% penetration. It may take three years or more for other countries to enter the 10%+ club.
I think your graph is flawed as a tool for understanding; a growth rate of 1% of total generation per year is 100%/year at 1% penetration, but only 10% at 10% penetration and 5% at 20% penetration. That gives you a y = 1/x curve.
If you graphed wind growth rate vs. fraction of total (not wind) generation, it would be much more obvious where limits start to kick in.
Perhaps, but wind has ramped some 30% per year, and the graph at least shows such ramping isn't very likely above 15% penetration. Perhaps not very surprising, though. The graph you are asking for would look like this:
However, here it is even more obvious that we have too little data yet. It seems it will take at least another five years before we have meaningful statistics.
Yes, but the peaks show why the averages struggle to get above a certain level.
Right now, Spain illustrates my point. Averages are below my 3x6%, they might make 4x6% long-term-average, but does anyone expect the wind long term average to get to 60%+. (10x 6%)
Spain's own targets are well below that.
Even now, to allow this level, there is significant redundant power capacity being cycled;
If you keep adding wind, eventually the only way to raise wind's _average_ numbers is to discard wind power at peak times. That further raises the cost of wind power, not lowers it.
- but the more important point I was making, is that current wind build rates, will bump into these practical ceiling globaly.
Spain is merely ahead of the pack, and already nicely shows the tapering effect I mentioned, as coming :
Added GW 2008-2009: 2.40848GW
Added GW 2009-2010: 1.52725GW
jg_
Yes, but the peaks show why the averages struggle to get above a certain level.
If a country has 18% energy generated by wind, a 10% growth rate is still going to result in 36% wind in less than 10 years.
The important figure is the world wide growth in wind at about 30% pa for the last 20 years. Many new countries are starting to add significant wind even if a few such as Denmark are "only" increasing capacity by 5-10% per year. If this was nuclear or NG fired capacity we would be calling a 10% growth rate booming expansion.
If you keep adding wind, eventually the only way to raise wind's _average_ numbers is to discard wind power at peak times.
two other ways are to use pumped hydro storage, or connect to a much larger grid when peak wind output will rarely exceed 70% capacity. A third way would be to use surplus wind power for example charging EV or heating domestic hot water.
Actually, the 2010 figures broke the trend with only 22% global additions.
Your alternatives either doesn't scale very well, and/or is expensive, unfortunately.
We'll see how Germany does now when they are going to retire their nuclear plants and introduce more lignite, NG and wind.
In 2010 China installed 29 GW of new renewable capacity (18.9 GW of new wind) and 17.5 GW of new solar hot water capacity (instead of installing electric/nuclear powered water heaters) and only 1.6 GW of new nuclear:
http://www.ren21.net/Portals/97/documents/GSR/GSR2011_Master18.pdf
Your alternative either doesn't scale very well, and/or is expensive, unfortunately.
As usual, you present raw nameplate capacity figures, but omit the fact that wind nameplate should be divided by three to be even remotely comparable to nuclear capacity.
And sure, wind is somewhat easier to ramp initially, but nuclear scales better and is less expensive, at least in China, fortunately.
China's nuclear ramping is impressive (30%-ish annually), but that is so far mostly visible in construction starts (since commercial reactor starts lag some five years behind construction starts). China's wind ramping is even more impressive, more like 100%-ish, but has less ultimate potential, unfortunately.
And sure, wind is somewhat easier to ramp initially, but nuclear scales better and is less expensive, at least in China, fortunately
Actually, because nuclear is more costly than renewables such as wind, hydro, biomass and solar hot water, China installs less nuclear than renewables, unfortunately. http://www.ren21.net/Portals/97/documents/GSR/GSR2011_Master18.pdf
China's nuclear ramping is impressive (30%-ish annually)
Actually, according to IAEA China initiated 0 GW of new nuclear construction this year, unfortunately.
At the same time China is not only ramping wind, solar hot water, biomass, waste incineration etc. but also PV:
http://www.pv-tech.org/news/china_revises_pv_installations_targets
Your alternative either doesn't scale very well, and/or is expensive, unfortunately.
China doesn't agree with your cost claims. As I said, wind is easier to ramp but has less potential.
And yes, it stopped ramping construction due to Fukushima. If you believe that stop will remain for long, then we'll simply let time prove you wrong. Regarding your link claiming Chinese PV installations of 10 GW to 2015 - that's a pathetic amount.
China doesn't agree with your cost claims.
Of course it does:
In 2010 China installed 29 GW of new renewable capacity (18.9 GW of new wind) and 17.5 GW of new solar hot water capacity (instead of installing electric/nuclear powered water heaters) and only 1.6 GW of new nuclear, because its obviously too costly: http://www.ren21.net/Portals/97/documents/GSR/GSR2011_Master18.pdf
Because nuclear is too costly, the Chinese nuclear electricity share is also below 2% even though China has been operating nuclear powered submarines since the 1970's.
Of course, one could also suggest, that China is ruled by Greenpeace and on the other hand France is Greenpeace-free. However, this is highly doubtful.
And if you read the PV link, you would have noticed that China plans to install 50GW of PV until 2020 besides all other renewables.
Anyone, you copied that first paragraph from a few comments up the tree, and cited the same link, and this is your standard operating procedure. In my humble opinion, you are conducting systematic forum abuse. You add repetitive noise, spam with links and are generally disingenuous.
You say China plans 50 GW of PV until 2020. That isn't worth more than some 10 GW of nuclear. China plans 80 GW nuclear by 2020, 200 GW by 2030 and 400 GW by 2050 (of which half shall be fast reactors). Then they have actually planned for 1400 GW fast nuclear reactors by 2100. Why would it plan that if renewables were more cost efficient?
The first four AP1000 they are building now is expected to cost less than $2000/KW, and later should be less than $1600/KW. Does wind match that? Perhaps, but at a third of the capacity factor. And would it matter if wind matched? No, since nuclear replace coal, while wind is merely extending natural gas and hydro. Different applications, different scope.
China plans 50 GW of PV until 2020. That isn't worth more than some 10 GW of nuclear.
Both nuclear and wind produce at night, which is less valuable. Solar is complementary to both.
The first four AP1000 they are building now is expected to cost less than $2000/KW, and later should be less than $1600/KW. Does wind match that?
Sure, even accounting for capacity factor, in China. Don't forget, everything is cheaper in China.
You might want to keep an eye on what China is doing.
Just a short time ago China announced that they were slowing their rate of building nuclear. They said that they might return to previous plans after they review safety issues. (And one would assume costs.)
At the same time China greatly ramped up solar and wind installation. With the falling price of wind generation and the plummeting price of solar it could be that China is redoing their math.
No one saw the rapid decrease of solar a few years back, all projections were made on a more modest rate of price decrease. The enormous price drops we've seen in the last couple of years are resetting plans.
(France, the other building of reactors, is getting into wind and solar in a meaningful way. Might be that they've recrunched their numbers. After all, they have some brand new numbers on how long it takes to build a reactor in Europe and how much it costs.)
To me, it seems they have slowed wind down. The latest bid I have is 100 GW 'till 2015, and as they already have 42 GW end 2010, that is quite little. Actually, it assumes they will slow down from the 16 GW addition they had in 2010 to 12 GW/year in 2011-2015. If this is so, nuclear will keep producing more than wind in China now and for the forseeable future.
I read the target as a minimum goal, not a cap. When it comes to wind, China has a history of reaching its target early and then setting a new, higher target.
China started to rapidly build hydro and solar hot water more than a decade ago, and its rapid nuclear expansion plans in 2004. Wind and solarPV much later. Its clear that China is expanding all as fast as possible and running into capacity constrains for all but solar PV.
All are needed to have any hope of reducing coal-fired. Nuclear and renewable seem now to be cheaper than coal at todays world prices.
Its hard to predict what will happen in 20-30 years, but at least in the next decade renewables will continue to be much more significant than nuclear, but the actual mix of renewables will probably shift to solar PV until daytime peak demand is met by solar.
I see no reason why nuclear, wind and solar PV cannot all contribute at least 20% of electricity demand, so all have a long way to go.
400 GW by 2050 (of which half shall be fast reactors)
Given the fact, that China hasn't even initiated one conventional reactor construction this year, this seems highly unlikely, unfortunately.
and later should be less than $1600/KW
This is your claim and not backed-up by facts, unfortunately.
Why would it plan that if renewables were more cost efficient?
Obviously, fact is that China builds and invests more in renewables than nuclear, unfortunately.
The Chinese nuclear electricity share would also not below 2% even though China has been operating nuclear powered submarines since the 1970's. If nuclear was really as cheap as you claim it to be, the nuclear share would be much higher than 2% and China wouldn't currently invest and build far more renewable than nuclear capacity.
Unfortunately, you seem a bit childish in your argumentation.
You link to a 116-page PDF without bookmarking or noting a page or figure number. This is closer to obfuscation than a reasonable attempt to provide supporting data.
I will note that Figure 1 on page 17 shows that, worldwide, nuclear energy provides 80% as much as all renewable electricity and 4x as much as wind. It barely mentions nuclear energy in China. Michael Dittmar's link 2 years ago noted a number of plants starting construction, mostly in China.
Which must be why China has 16 reactors under construction to add to the 11 in operation, and plans to build many, many more. China announced a molten-salt reactor development project on Jan. 25 of this year... obviously, because nuclear is too expensive.
Want to buy a bridge?
China has 16 reactors under construction to add to the 11 in operation,
And those 11 under operation produce not even 2% of the Chinese electricity (again China has been operating nuclear submarines since the 1970's but hasn't had any windfarm development until very recently).
Besides that China hasn't initiated any new reactor construction this year: 16 reactors under construction may be equivalent to about 3 reactors going online per year.
This is simply much less than the renewable capacity which is currently being added in China every year.
If nuclear was as cheap as some claim it to be, the opposite would be the case.
China announced a molten-salt reactor development project on Jan. 25 of this year... obviously, because nuclear is too expensive.
The rest of the world has several development projects with fusion reactors... Is this your proof that fusion reactors will produce cheap electricity?
Strange, most sources cite 26 under construction in China. That would some 6 reactors per year, which would be like 20 GW wind, which is more than the wind buildout, projected at 12 GW/year.
I disagree with Neil 1947 observations. Even it is always interesting to look into the rear view mirror to the evolution of global wind installed power in the last 20 years, it is a wrong methodology to extrapolate that the world will automatically follow the growth path of the subsidized and generally well economically endowed pioneers.
As ASPO dos with the patterns of depletion of many oil deposits and fields in regions and countries in the world to extrapolate to the world the approximate pattern to the global peak oil, in wind generation, it is also essential to extrapolate the raise BUT ALSO DE FALL (nothing grows indefinitely) of the pioneers in the growth patterns, to learn on how much the rest of the world will presumable behave.
The problem here is that our records on pioneers are recent and hardly show the slow down of their progresses, for whatever the reason, although we have some hints form Germany, Spain and Denmark, be them for saturation of geography of good wind fields or because the economic crisis limiting the subsidies or nay other reason.
And of course, also to consider that in many countries in the world, the lack of financing and the lack of even most basic infrastructures (among them electrical networks) will not allow to automatically extrapolate those of the forefront to the rest of the world. Much on the contrary, take a brief view of what is happening in the world with the brownouts and blackouts and you will see that investment perhaps should rather go to critically maintain many electrical networks to avoid their definitive collapse than to experiment with subsidized wind farms.
Some remarks here:
I do not know where jg_ data bases come from. I quote the official data bases of the government institution, Comision Nacional de Energía (CNE) in his last released report June 2011 Added wind GW in Spain:
2008: 1.786
2009: 2.520
2010: 0.806
Half of 2010: 0.369
I agree that adding wind power in a given isolated electrical network reaches a moment in which more and more parks have to be switched off the net more hours in peak times, when base load (in Spain basically nuclear and coal fired power plants than can not be switched off on short advice or notice as per the wind variations). And this raises, like the case of Spain, many claims of the wind power plants owners that they are complying with the initial, theoretical number of nominal hours a year they were expecting in their business plans as per the on site preliminary studies.
But on the other hand, there is another indirect ways for wind power to raise wind average: the decrease in the national demand of electricity because the deep economic and financial crisis. As renewable energies have priority to enter into the network by law, this automatically increase the penetration percentage.
That may be above 6%, but not by much. 2x, maybe 3x ? ie No one would claim 60%-Grid makes sense.
Note: It's primary energy not electricity.
1 TW * 8760 h = 8760 TWh which is roughly 50% of the world's electricity consumption. (And I agree 60% wind doesn't make much sense currently).
Of course one must also ask:
1. Why does wind power have to substitute that 65%-portion of the primary energy which went through the cooling towers?
2. If fossil heating systems would be replaced by heat pumps, why would wind power not benefit from the fact that a modern heat pump (flexible demand) requires only 30% of the input energy of a fossil furnace?
3. If cars would be electrified (flexible demand), why does wind power have to substitute 75% of the primary energy which is currently lost in the exhaust and cooling system?
By the way in March Spanish wind farms covered 21% of the electric demand:
http://www.windpowermonthly.com/news/1063600/Spanish-wind-record-month-M...
Flexible gas and hydro power plants are primarily needed to deal with unsteady demand and these flexible plants were mostly already there before most wind farms were installed.
Luckily Spain has wind power to back up hydro when there's a drought:
http://www.reuters.com/article/idUSL1579694720080415
The wishful thinking seen in many of these comments is amazing. It's hard to imagine how many long time readers can still hope for the kind of complex society we have at present. Get real, please. Sustainable societies will look nothing like our current societies and won't need anything like the amount of energy, so let's stop wishing that wind, and other renewables, can continue our way of life.
Here we have one piece of research about the limitations of wind. Another was reported on in New Scientist a while back. We need to encourage studies that try to honestly look at the sustainable amount of energy that we can extract from earth's energy systems, without causing unintended consequences. For me, that means looking at the energy issue from the other perspective - not how much can we generate but how much do we need for lifestyles that are sustainable? Energy is but one aspect of sustainable societies. There are all sorts of other limits and critical boundaries which we are already exceeding or close to exceeding.
This site concentrates on energy but energy isn't the only factor in our predicament and there is no "solution" to energy that doesn't involve other factors in some way. Wishful thinking is not a solution.
I wonder what you mean by "our way of life"?
If you mean that we will live with less lighting in our homes and places of work, I doubt it. Most likely we'll live with the same amount but produce it with ~25% of the electricity we now use. Incandescents -> LEDs/CFLs.
If you mean that we will walk significant distances rather than ride, I doubt it. Most likely we'll move from petroleum based transportation to electricity for both personal and moderate distance public transportation.
If you mean we'll downsize our TVs and de-power our electric toys, I doubt it. We'll just make better versions which run on a fraction of the power the old ones used.
If you mean we'll huddle, cold in our homes, I doubt that too. We'll use better insulation/efficiency measures along with more geothermal heating and heat pumps.
Now, I'm not too worried about collecting too much solar power. Rather than let the Sun hit our roofs and radiate off as heat, we'll grab it with solar panels, turn it into electricity, let the electricity do some work, and then that captured solar energy will end up as heat at the end of our diversion.
The same for wind, wave, tidal and hydro. We'll use some of each, but not enough to throw the Earth off balance.
Still jobs to do, a need to figure out sustainable solutions for some of our consumption, but no obvious "can't do" issues. Just opportunities for bright, inquisitive minds.
Perhaps....or perhaps a scenario by the Bundeswehr will be closer to actual events;
http://www.energybulletin.net/stories/2011-06-13/review-bundeswehr-repor...
I'm disappointed to see something so deeply unrealistic from the German military.
I guess the US military has no monopoly on fear-peddling.
The US military is busy greening up its act.
It's installing wind and solar at bases. It's developing portable solar for forward deployment.
It just announced a huge program for rooftop solar on its residences in 33 states. Total build out will double the amount of rooftop in the US and help drive prices even lower.
And it's flying jets on biofuel.
Interesting that the German military would be so backwards when the German people are leading the way with renewables....
"The US military is busy greening up its act."
I hope this was intended as a joke, but I fear it wasn't.
Their business is killing people and destroying things. No window dressing will ever make that basic occupation 'green.'
OK, I'll reword it.
The US military is busy greening up its power systems.
The US military seems to not adopting the doomer outlook of the German army....
And how much will all this cost? $100,000 to $200,000 per family? Only the well off can afford this.
LED bulbs? Small money up front followed by significant savings.
Better insulation? Modest money with reasonably quick payback.
An EV? A few thousand dollars more than a comparable ICEV but much lower 'fuel' payments which will mean about the same monthly expenses until the vehicle is paid off. Then a few hundred dollars more in pocket.
A more efficient TV/electric toothbrush/gameboy? About what they would pay for the replacement anyway, except this replacement will be cheaper to power. This is already happening, consumer goods are getting more efficient. Your new power bricks are not the phantom loads your old ones were.
A geothermal heat pump? Some medium money up front but paid off by savings in fuel oil costs.
Some improvements in efficiency will come along with normal replacement. Other changeovers will finance themselves.
A solar array on the roof? Payments to pay off the array rather than to buy the electricity that the panels provide. For the 6 - 10 years it takes to pay off the panels and then a few decades of almost free electricity.
I don't see any expenditures over what would normally be spent and significant savings some short years after switching. The least well off are the ones who should benefit most, they don't have money to waste on buying extra energy.
Never heard about Jevon's Paradox?
Never seen the IEA WEO's where to each increase in GDP there is a linear very well correlated increase in primary energy consumption, globally speaking?
It is the system what has to change, not the technological gadgets or technofixes. What somebody called "our way of living" and somebody else questioned on what that meant
Jevon's Paradox?
Sure...who cares? If consumption can't increase, it won't.
IEA WEO's where to each increase in GDP there is a linear very well correlated increase in primary energy consumption
1) correlation is not causation - Ayres' research shows that primary energy inputs only account for 13% of change in GDP.
2) this study is highly unrealistic - withdrawing 1.2TW will deplete an overall wind system of 1,200TW??
3) we have plenty of other sources: solar, nuclear, etc.
Sure, I've well familiar with Jeavon's Paradox.
Just as soon as I can get my hands on some LEDs I'm building on 4x as many rooms to my house so I can leave more lights on.... ;o)
Each increase in GDP... How do you deal with the fact that California residential electricity use has been essentially flat since the 1970s? CA has learned how to do the same as everyone else while not drawing more power.
We could change the way we live and fix a lot of our energy problems. Now go down to the local mall, pub, whatever and take a good look at the people there. Think you could talk them into drastic changes in their lifestyles?
The way out is to find ways to keep our lifestyles roughly the same while transitioning away from fossil fuels. We do that by installing renewable energy generation and at the same time cut usage through efficiency. People will not readily accept making uncomfortable changes. They will choose short term comfort over long term survival.
I would venture that we can change the way we live and fix ALL our energy problems. Which begs the question, if solutions are just a matter of lifestyle change, are the problems REALLY problems?
Or are just a bunch of people pissed off that they can't guzzle gas, or coal fired electricity, or whatever else they WANT to do just because they feel it is some natural right as (fill in your citizenship).
I think it's unfair to blame the consumers.
The producers are the ones blocking change: oil, car, coal companies.
I sort of don't agree with either of you.
While we could solve our problems by changing our lifestyles, that is extremely unlikely to happen (unless forced).
People, in general, do not sacrifice today for tomorrow. Most people get close to retirement age before they start saving for retirement and there's overeating....
Corporations will give people exactly what they are willing to pay for. Want SUVs enough to purchase them? Car manufacturers will crank them out. Want EVs or super-efficient ICEVs? Car manufacturers will switch over their assembly lines.
Now something I do agree with is the role of oil and coal companies in slowing the transition. You can start with the coal-funded Tea Party and move through all the opinion pieces on why wind and solar don't work and how EVs will never gain range or drop in price.
And don't forget the fossil-fueled legislators who block green legislation and continue subsidies for oil companies.
Corporations will give people exactly what they are willing to pay for. Want SUVs enough to purchase them? Car manufacturers will crank them out. Want EVs or super-efficient ICEVs? Car manufacturers will switch over their assembly lines.
Car companies would like you to believe that they just make what people want. But, the role of car companies in shaping public policy is actually much clearer than for oil companies.
Start with GM tearing up mass transit right after WWII (as documented in court files). Continue with GM's ex-CEO (Charley "engine" Wilson) as SecDef building the heavily subsidized interstate highway system in the 50's. Follow with intense opposition to strengthening CAFE regulations in the 80's and 90's. Create further delay by killing the Clinton administration push for hybrids (PNGV), and replacing it with the great hydrogen red herring in 2001. Finish by killing the EV-1, RAV-4 EV, etc.
Yes, car companies attempt to drive the market through advertising. But they manufacture what sells. When fuel prices soared a couple years back they cut way back on truck/SUV manufacturing and started bringing out more efficient models.
The EV1 and Rav4 EV were introduced before battery technology was up to the job. And the price of oil dropped.
Hydrogen looked like the route away from oil, but then battery technology improved.
We're entering a new era where fuel is going to get more expensive, and then get more expensive.
Meanwhile, demand for the Prius sank to the point where Toyota had plenty on the lot (completely opposite to the situation from '04-mid '08 or thereabouts), and there are consumers who insist they MUST have a 1-ton 4x4 pickup and won't consider buying a CF bulb.
There's plenty of blame to go around.
demand for the Prius sank to the point where Toyota had plenty on the lot
Are you sure? I thought the decline in sales was primarily due to supply-side problems.
If demand fell, the cause is probably Toyota's recent quality problems. An example of the difficulties caused by domination of a market by a single manufacturer.
Toyota had a temporary sales problem for all its cars as a function of the reported sticky accelerator problem. (Reported, but in all/most cases operator error.)
Toyota recently sold their one millionth Prius in the US and have sold over two million worldwide.
Nick wrote:
1) correlation is not causation - Ayres' research shows that primary energy inputs only account for 13% of change in GDP.
Then try to do the work that the world makes today with 12 billion Toes/year consumption with human bare arms. Do a more precise cite of Ayres. IAE shows an almost straight line for the world when depicting in many WEO’s (i.e. WEO 2009. Page 59) with the GDP in the horizontal axis and the primary energy consumption in the vertical axis in a large number of years analized (i.e. 1971 through 2007)
2) this study is highly unrealistic - withdrawing 1.2TW will deplete an overall wind system of 1,200TW??
You did understand nothing. Withdrawing 1.2 TW will deplete 1.2 TW in an overall 1,200 TW wind system; exactly the same than increasing 280 ppm to 380 ppm of CO2 increases only 1/10,000 the CO2 content in the atmosphere of the planet, which has 0.036% of CO2 content in its turn. But this does not mean that 1/10,000 interference on natural global contents must not have a global importance and provoke irreversible consequences on the whole planet. And you are talking of interfering 1/1,200 of the overall wind planetary system and some others even 1/120 as if it was so easy and viable.
3) we have plenty of other sources: solar, nuclear, etc.
Yes, and helium 3 for nuclear fusion and wind kite generators at big heights, but we should first await a little bit to see how much of that can really be harnessed in a proven, commercially, feasible, social accepted form.
Bob Wallace wrote:
Just as soon as I can get my hands on some LEDs I'm building on 4x as many rooms to my house so I can leave more lights on.... ;o)
Technofixes technolatry...
Each increase in GDP... How do you deal with the fact that California residential electricity use has been essentially flat since the 1970s? CA has learned how to do the same as everyone else while not drawing more power.
Easy. This is a very interconnected world. If a given region or country DEMATERIALIZES its activities (i.e. the City –London-, living, in an importance percentage, of handling financial controls of prices and retaining big margins in financial operations on a lot of physical activities of factories around the world), then it can have a substantial economic growth without increasing its energy consumption. It is also known as outsourcing the shit and keeping the
Now forget about a specific place of the world and take the world as a whole, since the industrial revolution. Then, show me a moment in 150 years in which we have decreased substantially our energy consumption and increased significantly our way of living. Just in case, discount the growing divorce of the devaluated paper money, since Bretton Woods rupture in 1971, printed since then without any relation with the supposedly equivalent physical goods (gold being the traditional one) or proven, measurable, effectively made services to which they were supposed to represent.
try to do the work that the world makes today with 12 billion Toes/year consumption with human bare arms.
How about just going from .2 liters of fuel per km (Chevy Tahoe) for personal transportation to zero liters and the equivalent of .02 liters in the form of electricity (Nissan Leaf)?
Do a more precise cite of Ayres.
Here you go: http://www.iea.org/Textbase/work/2004/eewp/Ayres-paper1.pdf
this does not mean that 1/10,000 interference on natural global contents must not have a global importance
That's an interesting speculation, but it has nothing to do with the argument of the Original Post, which is about depletion.
we should first await a little bit to see how much of that can really be harnessed
Absolutely not. Delay the ramp up of renewables? Why? To preserve the profits of coal and oil companies a little longer??
Technofixes technolatry.
Bob was using irony: http://en.wikipedia.org/wiki/Irony
show me a moment in 150 years in which we have decreased substantially our energy consumption and increased significantly our way of living
Show me a moment in 150 years in which we have decreased substantially our candy consumption and increased significantly our way of living! Again, correlation is not causation.
United States, from 1978-1982: reduced oil consumption by 19%, increased GDP by 2%.
That's not the whole world, but it's pretty suggestive.
Again, it's perfectly clear that transportation can move the same freight with 1/3 the energy; passengers can reduce per-km energy consumption by 80%; lighting can get reduce joules per lumen by 50%; homes can go to PassiveHaus; etc, etc.
The high altitude wind systems should give a much higher f3 value than that reported in the article. Because systems can operate in farm where control can pilot the systems in order that they do not interact with each others. ALso there are different devices, with kites in cross wind motion, that have been tested, that can intercept an area that is comparable with pi*h^2/2.
By the way, Miller paper (Jet stream wind power...) has been commented by Bergmann
http://www.earth-syst-dynam-discuss.net/2/435/2011/esdd-2-435-2011-discu...