The energy efficiency of energy procurement systems

Energy Controversies lecture series, University of Aberdeen, 5th February to 30th April 2009.

Some ERoEI data sources wind, tar sands, ethanol, solar pv and references therein. Nuclear: M. Lenzen, Energy Conversion and Management 49 (2008) 2178–2199. Hat tips to Will and Nate for solar and nuclear sources.

"We are set on a disastrous course. Governments must accept that the way we use energy must change and that a painful period of adjustment lies ahead. The energy efficiency of energy use and procurement should lie at the heart of decision-making and a good starting point is to ensure that reliable efficiency data is available to guide this process."

Energy efficiency now supposedly lies at the heart of EU and US energy policies. Whilst we are most aware of the merit of energy efficiency of energy consumption, e.g. fuel-efficient cars and well-insulated buildings, the concept of energy efficiency of energy procurement is one that has been largely overlooked. One reason for this has been the vast energy surplus provided by historic supergiant oil and gas fields of the Middle East, Russia and the Americas and vast surface coal deposits of Africa, Asia and Australia. As production from these historic fossil fuel deposits starts to decline, the OECD economies are being forced to procure energy from other sources such as wind, tidal, solar, bio-fuel and nuclear. Without most of us being aware of the fact, it has suddenly become important to understand the energy efficiency of new energy procurement systems, if industrial society as we know it is to survive the next great energy transition away from fossil fuels.

The Energy Return on Energy Invested (ERoEI) provides one measure of the efficiency of energy procurement and is quite simply defined as:

Energy procured / Energy used to procure energy

The chart shows how the proportion of net energy available for society to use varies with ERoEI. There is in fact much uncertainty in the data displayed and many large gaps in knowledge. The shape of the curve shows that for ERoEI > 10, the bulk of energy procured is available to society – to power industry, transportation, schools and hospitals. With falling ERoEI < 10 there is an exponential increase in the amount of energy required to procure energy with a corresponding decline in net energy available for society.

The chart is not zero scaled and shows that for ERoEI = 1, no net energy is produced. The yellow arrow, pointing to ERoEI = 9 is intended to provoke some debate since we do not know with any certainty what the minimum ERoEI for modern industrial civilisation is.

One thing that we do know for sure is that we have used a significant proportion of the easy to access fossil fuels and that new resources scheduled for exploitation will require much larger amounts of energy to procure. The average energy pool available to the global economy is therefore relentlessly marching towards lower aggregate ERoEI. As society uses more energy to procure energy, an inevitable consequence is that less energy is available for everything else, in a stable energy production environment. Certain areas of current energy use must fail and the way the free market is trying to resolve this problem is to select energy intensive industries for extinction, for example air travel and motor vehicle manufacture, however, current Government policies are trying to prevent this natural selection process, propping up the motor industry on both sides of the Atlantic, expanding airports, whilst subsidising inefficient means of procuring energy such as temperate latitude bio-fuels.

We are set on a disastrous course. Governments must accept that the way we use energy must change and that a painful period of adjustment lies ahead. The energy efficiency of energy use and procurement should lie at the heart of decision-making and a good starting point is to ensure that reliable efficiency data is available to guide this process.

Well said Euan. Energy and natural resources are what we have to spend. And those with the money currently control the energy. How we spend our energy is of the utmost importance.

There are two other related issues I would address:

1)Non-oil energy technologies 'harness' energy with very different properties (density, intermittency, spatial diffusion, etc.) than oil - nor are all energy alternatives of equivalent quality with respect to social use/demand. The current crop of economists parse all commodities into money - which in the process nullifies all physical differences between the commodities themselves. This leaves the market especially unqualified to predict any change in physical relationships between the commodities that society may depend on that have production time lags more than a few months to a year. Electricity is currently more expensive per BTU than liquid fuels, yet in the coming years, liquid fuels will become much more limiting. So the net energy graph you indicated, to be holistic, must account for TIMING of energy flows, and the TYPE of energy that societies infrastructure currently, or in the future will require. On a business as usual path, liquid fuels will be the dominant limiting energy input for some time to come.

2)the reason ERoEI in itself isn't the whole story is it assumes non-energy inputs remain in constant proportion whichever direction the energy efficiency of energy procurement (ERoEI) moves. If a low ERoEI process (say 3:1 netting out 2) replaced a higher ERoEI technology (say 9:1 netting out 8), this in itself wouldn't be deleterious. The problem would arise if 4 times as much of some other limiting input also had to be used (like land, water, soil, GHGs, etc.) High quality crude oil required little of these other inputs so a big problem in moving to lower energy gain systems is the vast amount of non-energy inputs required. If a 3:1 process Z somehow didn't need any land, water, minerals, etc. we could scale it Z^n times and it would solve the energy crisis. In sum, net energy is the KEY statistic policymakers should be spending resources in trying to assess, but they also need to look at natural resource returns on other limiting resources. We should be optimizing the return of a portfolio matrix of limiting resources, many of which are currently not included in the market system, and others which are priced incorrectly (due to economists conflation of biophysical work necessary outside of 'dollars').

In sum, it is feasible that new oil and gas fields have far inferior 'energy returns' (and financial returns) than SOME alternatives. So even though spending energy on them would be better allocated elsewhere, we need those liquid fuels in order to create a demand side infrastructure that can thrive beyond oil. So again, ERoEI is vital, but TIME and QUALITY need to be considered as well.

The current crop of economists parse all commodities into money - which in the process nullifies all physical differences between the commodities themselves.

Well, presumably the current crop believes that prices are the result of marginal conditions (the intercept of supply and demand), which means that the prices themselves are specific to a particular set of circumstances. This has always been a problem with aggregate measures like GDP, national wealth, and the like. Various policies, reallocations, etc., change the prices, or so the theory goes. Economists frequently ignore their own theory on this point, though...

More to the point, I've been lurking these boards for a little over a month, and a lot of the issues related to energy "aggregation" remind me of the capital controversies that have emerged over various periods in the development of economic thought. The Cambridge rounds seem the most relevant, when the question was roughly about whether capital could be sensibly thought of as some aggregate, in the presence of heterogeneity of the underlying goods (the "sensible" applies to the notion of a supply of capital). A billion dollars of tractors cannot be magically turned into a billion dollars of greenhouses...

In a growing world with no forseeable limits, I think capital COULD be aggregated as such. Now I don't think it can (though most would disagree).

Yes, I disagree ... it never could be, so it still can't be. Or it always could be and it still can be.

Depending on whether you mean plant and equipment and productive capacity, or accumulated stock of financial assets. With the former, the aggregation for the normal purposes was always a polite fiction, while with the latter, it still can be aggregated, its just that people don't like to do it because they don't like what's happening to the total given the "financial obligations that can and will in fact be met" qualification.

Consider modern capitalism as an economic system that allocates its resources by encouraging individual citizens to decide to which group of strangers engaged in productive enterprise to entrust their wealth tokens, they being motivated to do so by a common expectation that the value of the obligations thereby created will become greater than that of the wealth tokens they handed over.

Whatever your definition of "capital", whatever your view of whether it could in the past be accumulated, or will in the future be capable of being accumulated, permanent economic contraction seems likely to bring the end of capitalism as a dominant feature of civilization.


Might not some of the other factors be converted into energy equivalents since energy use would be involved in transforming or acquiring those resources. In other words, things like transporting water to a site would involve second-order ERoEI inputs. In each of the cases I have been looking at, the limiting factor (other than energy) could be mitigated if we had the energy to do so. Thus it still comes down to an energy problem when looked at that way. At least that has been my thinking. Interested to hear your thoughts.


Technically yes, but the amount of energy to remediate polluted water from say tar sands or Marcellus nat gas drilling would be extreme, and to parse that into energy terms would then make the energy return less meaningful - energy return is the biggie no doubt, but in the end we need a portfolio approach, just like in finance. To take it one step further, we want the highest return on scarce resources adjusted for risk (not just mean return). Same goes for energy (high standard deviation on biofuels, solar, wind, etc. though with more installations the dispersion on techs like wind decreases).

Nate, I believe the word for what you propose is "hubris".

cfm in Gray, ME

And those with the money currently control the energy. How we spend our energy is of the utmost importance.

Ahem, shouldn't that be how THEY spend THEIR energy? is of utmost importance to THEM .

From where I sit, in a position where I don't control much of anything, I'm getting the impression that those who do control the energy don't give a rodent's rear end about the rest of us. Maybe I missed something?

They dont know us personaly so why should they care about us? It is part of human nature to only care about those who are close to us or people we have a connection with, friends and family.

Hi Nate

I don't have the time or expertise to do it, but somebody should put together a post concisely summarizing the key factors our governments should consider when evaluating energy sources -- i.e. Which sources deserve the most priority in allocating our dwindling energy/nat.resources/time. There's a lot of good discussion, but I haven't seen a post that sums it all up.

Perhaps the list should look something like this:

1. ERoEI > 1 (& the larger the better)
2. Rate of net energy production
3. Non-energy inputs for energy procurement (ex: water, land, top-soil, forest, metal ores, etc.)
4. waste output absorption limitations (ex: CO2, radioactive waste, heavy metals, waste heat, etc.)
5. Inputs required for infrastructure build-up/upkeep (ex: energy rosources, steel, copper, time, etc.)

These are just off the top of my head. Someone really smart at TOD should maybe prepare something along these lines that could be sent to the King -- like Heinberg's Real New Deal document.

thanks -- Dan

I would add payback period to your list. Longer is worse, especially in the present economic climate. The longer the payback period, the longer it is until the capital investment is recovered and freed to be re-applied to other capital projects. Longer payback periods also tend to be associated with more iffy assumptions and uncertainties; what is supposed to be a 25 year payback period could easily end up actually being 30 or 40 or 50 years - or never. At a certain point, you also have to start looking at how the payback period stacks up against the useful life of a project; you want to avoid getting on a "treadmill", where as soon as a project has broken even, you have to start thinking about replacing it.

We just don't have the horses to accomplish this in our spare time. Mandating that energy efficiency of energy procurement happened in the 1970s but has long been forgotten - data is sparse - I send this stuff to API, Matt Simmons (who recently said we nee $100 TRILLION to upgrade our rust/iron ore in energy delivery systems - I haven't heard back) -very few view the problem in these terms because they (like I) have been trained in dollars - you have to be able to look out a few steps -Chu/Holdren and others should be conducting massive research on this topic and it should be married with equivalent research on our 'ends' somewhere else in government. Instead we will evaluate things via the fantastically fast moving target of dollars.

Your suggestion is a good one - but someone more connected than us is going to have to step up -we've tried for years to even get people thinking in these terms - and many before us as well (this is related to Technocracy movement of 70 years ago...).

At least there are scientists in DC now - but even scientists succumb to politics, and the needs of the moment - they just draw the line sooner (or they should).

Nate certainly has it right, this needs to be done at the top, where the resources to do it could actually be mustered. but...

I vaguely remember back in the day Nixon giving a speech and pointing up America's current and potential productivity (I think he was equating GDP with productivity) PER SQUARE FOOT. I remember cringing, since the long term costs incurred by that productivity were always ignored. Back then these costs were always very poorly defined and lumped into that amorphous under the radar blob called 'social costs' (calling attention to their potential enormity never endeared me to my economics instructors either). By the end Reagon's time 'social costs' weren't even mentioned anymore. Short term positive cash flow had become the only god worshipped.

The challenge of trying to get a true benefit cost analysis factoring long term costs and long term benefits--which takes in every aspect of as much of the ERoRI equation as can be humanly modeled--into all government policy making is immense. It would be an almost a complete about face from what we have been doing for a long, long time. That some are undaunted and trying to do this yet is more than admirable. Unlikely as this about face is to happen, it is this society's only chance of going forward more or less whole.

Nate - I agree that non-energy inputs and outputs (pollution) need also to be considered and I believe what you are saying is that they may not be linearly correlated with ERoEI, tending to increase disproportionally towards the low end. And so I have to agree with that. But the point is that they are still positively correlated and ERoEI tends to underpin the cost of the whole energy procurement system.

The other issues of quality of energy outputs is of course vitally important. It may be argued that the quality of intermittent wind is lower than controlled hydro is lower than continuous output from nuclear. But that picture might change with plug in hybrid infrastructure that allows intermittent wind to be stored and to become more comparable with liquid fuel once it is bestowed with the quality to be used on demand for transportation.

Its kind of like in the old days when naptha was released into rivers since it was kerosene for lighting that was the target of refining. Along came electric lights, devaluing kerosene (for a while) and the internal combustion engine, transforming the value of naptha.

I would agree with this and am aware it is a framework valuation mess. But I am confident using something incorporating biophysical assets without corresponding markers will be beneficial to society in the intermediate and long run. As esoteric as these discussions become, hopefully someone will use pull these principles together into something meaningful. At what point does $1 trillion Swiss Francs or $500 billion US dollars change in it's ability to reflect true capital? Sometime soon methinks.

"The yellow arrow, pointing to ERoEI = 9 is intended to provoke some debate since we do not know with any certainty what the minimum ERoEI for modern industrial civilisation is."

Yes, I feel a bit provoced about it - when looking _only_ at ERoEI, the real limit is 1.0 - anything above would do. The ERoEI doesn't say anything about the timeframe from the energy investment until the energy return, and it doesn't say anything about what other resources had to be invested, etc. Reductio ad absurdum, if we had some way of harvesting unlimited amounts of energy at ERoEI 2.0 - invest one unit of energy and get two units of energy back within one month - of course that would be sufficient to sustain the "modern industrial civilisation".

Definitively, ERoEI is an important concept, and people should be more aware of it. It seems that in the public mind, quite often one technology is considered to be "silver bullet" that will rescue us and allow us to continue living our current livestyle. Ten years ago it would be "the hydrogen economy" - which isn't at all a solution to the energy crisis as hydrogen is just an energy carrier and not a source (ERoEI below 1). Five years ago it would be "biofuels".

With biofuels, people have become aware that it's problematic as one either would have to either clear forests or convert from food production, but most people are still not aware of how much oil is needed for producing fertilizer, etc, and hence the low ERoEI. Still, as long as the ERoEI is above 1, and if the production is supported by biofuels, the problem (and limiting factor) is really the amount of farmland spent, and not the low ERoEI - or said another way, the thing that really matters is the net energi output pr land area, and not the net energy output pr energy invested.

if we had some way of harvesting unlimited amounts of energy at ERoEI 2.0 - invest one unit of energy and get two units of energy back within one month - of course that would be sufficient to sustain the "modern industrial civilisation"

Well if you doubled your money in a month that would 24 doubling in a year and maybe 480* over the 20 year life cycle of your magic source - so the ERoEI would be very, very high - maybe 500, and so of course this could sustain industrial civilisation.

Still, as long as the ERoEI is above 1, and if the production is supported by biofuels, the problem (and limiting factor) is really the amount of farmland spent, and not the low ERoEI - or said another way, the thing that really matters is the net energi output pr land area, and not the net energy output pr energy invested.

If the ERoEI is marginally above 1 and production is supported by bio-fuels then the vast energy surplus that powers industry, transport, health, education etc is gone. In fact everyone is out in the fields planting and harvesting corn. Not quite our modern version of industrial civilisation. But the point about land (and food) availability is a good one. But the point is that this becomes an issue owing to the low ERoEI. Grow a fuel crop that has ERoEI of 50 and you wouldn't need all that land - which is in fact the observation you make - "net energy output per land area" - so we do in fact agree.

Well if you doubled your money in a month that would 24 doubling in a year and maybe 480* over the 20 year life cycle of your magic source - so the ERoEI would be very, very high - maybe 500, and so of course this could sustain industrial civilisation.

You appear to be defining EROEI in a reference to a specific time period. That is you are taking the energy output after a year's time and dividing by the energy input at the beginning of the year and calling this EROEI, thereby ignoring the disappearance of energy in the intermdiate doublings. This quantity is not EROEI as defined by Charlie Hall. However, in this conception lies the seed of the real signifcance of net energy. What is really important is not the ratio of output to input but the ratio of net output to non-energy related production resources such as labor, fresh water etc.
If you could produce energy by waving a magic wand and having one batch of energy disappear followed by the materialization of a new batch with a even larger amount of energy, then even an energy producing process with a very small output/input ratio could produce enormous amounts of energy as long as the time period required to cast your spell is short enough. What matters in this case is net energy/magician hour not the ratio of output to input.

As I have explained many times if we define the energy utilization rate as µ=Net Energy/Gross Energy and if R is the amount of some non-energy resource (e.g. labor, fresh water, etc) required to extract 1 gross unit of energy then the amount of resource required to extract 1 net unit of energy is given by:

RN = R/µ

As the energy utilization rate goes to zero the resource intensity of net energy production goes to infinity. It is the land and water intensity of biofuel production that will limit the scale of biofuel production rather than energy balance per se. The water intensity and labor intensity of shale oil production are likely to be the limiting factors of production for this fuel source and so forth.

Aren't there serious problems with commensurability in that approach, of both between non-energy and energy resources, as well as within these categories themselves?

I am not sure what you mean about commensurability. Economics is ultimately about use value which depends on complex interactions between many factors (including human psychological perceptions) and thus can never be completely expressed by a single objective scale of measurement. Get used the the real world. Physics, chemistry, biology, etc. can illuminate economics, but reduction of economics to completely objective equations is not in the cards.

Roger - what I'm trying to convey is the fact that life cycle energy costs for any procurement system need to be taken into account - which I believe is correct. It was the person I was responding to that took a very short time period view of the problem.

For biofuels, I agree that water and land availability are limiting factors along with natural gas. But I say again, these are only issues because of the low ERoEI. If corn-ethanol had eroei of 50 then it would not be an issue and our farmers would all be extremely wealthy and the only problem we would face would be Jevons paradox.

I need some time to consider RN=R/µ


I don't think the problem is as simple as 'net energy' of ER0EI.

We must consider the 'total energy' involved, we have to produce all the 'energy in' as well as the 'energy out' - this is not simply a ratio, it is an amount.

Your graph is only two dimensional, in order to see the real challenge we face somehow it needs to show how the total amount of energy possible is constrained by the ability to scale each technology in the third dimension.

As an example: Production of bio-fuels will have some Liebig's minimum - the amount of land available, or phosphorus maybe, but most likely it will be lack of credit - at an ERoEI ratio of say 2:1 you have to produce 3 in total to get a net 2 from, at best, a limited land area.

How does the technology scale to match current FF production at ERoEI of >50:1? What proportion of current FF demand could each technology replace?

ERoEI alone does not tell you the answer.

ERoEI alone does not tell you the answer.

Xeroid, you're exactly correct, of course. It is just a good step forward.

xeroid - I agree that a third dimension would be useful and have thought about it. The chart is really one dimensional showing a curved line (feeling I may get squashed here for poor mathematical understanding).

I though we could make this into a 2D (3D?) curved surface tracking the aggregate ERoEI of energy sources with time - in the second (third?) dimension.

How to scale this for amount of energy procured will require some thought but it is very important. We can easily tolerate procuring small amounts of low eroei energy, subsidised by very large amounts of high eroei sources. The problem arises as the amount of high eroei source declines. I believe that the dash for ethanol has actually distorted our aggregate energy procurement system in a negative and measurable way and unfortunately there is little sign of this being rectified.

Another problem of course is that we have so little input data, it is hard to quantify these important issues. What is the ERoEI of Ghawar's oil?

Tobixen, the real limit of ERoEI for absolute usage is 1 of course. But here we are talking Cheeta - ie if the cheeta gets as much energy as it uses in hunting the gazelle and surviving until the next hunt all is well. The yellow arrow is about what ERoEI is needed to sustain industrial society as we know it. Industrial society as we know it does not just feed its citizens. It also houses them, provides them roads to drive to work to make windmills etc. The ERoEI as used has to reach a certain level to sustain the infrastructure needed to continue to generate more energy. It has to produce enough food to free substantial number of humans from farming (non fossil fuel farming was close to ERoEI of 1, but that meant that virtually everyone needed to farm)

You can either factor all this into ERoEI (with difficulty) or you can use just primary energy inputs to calculate ERoEI and then set some level needed to maintain industrial civilization.

No, the number is way above 1. At close to 1 the proportion of the human economy dedicated to producing energy grows exponentially and in turn, the scale of the human economy within the natural economy becomes untenable. It already is untenable.

We need way above 1 to maintain a human economy and a natural economy. Maybe turn the problem around - if we only used energy sources 10 and better, then what sort of economy could we have?

cfm in Gray, ME

Still, as long as the ERoEI is above 1, and if the production is supported by biofuels, the problem (and limiting factor) is really the amount of farmland spent, and not the low ERoEI - or said another way, the thing that really matters is the net energi output pr land area, and not the net energy output pr energy invested.

But the total amount of energy that has to be produced from the biosphere, and hence the total amount of land needed, becomes very large for small EROIE, as shown below:

As long as we're analyzing the ERoEI graph, consider "sensitivity".

Park yourself at your favorite ERoEI (on the horizontal axis) and consider the %Energy available (vertical axis).

Now make small variations in ERoEI and see the effect upon %Energy.
Do this for historical oil field returns (> 30) and then for the minimum (9) and then for the ERoEI under discussion (1).

Is it really a good idea to be in a region where we jump around like that? Does variation in wind power really look that bad in comparison?
(It will come as no surprise that I dont' know the answer to those questions.)

I think you are talking about the slope of tangents to this curve:

Right -- i.e., I was referring to the first figure in the article. The slope approaches zero at large ERoEI (i.e., small fluctuations) and shoots up ("diverges") for small ERoEI (i.e., large fluctuations).

(Ain't MathCAD nifty!)

the ERoEI is simply inversly related to the total percentage of energy expenditure needed to run the ecconomy.

if civilization needed 10 LJ to run (L being a made up unit scale), all that matters is that the hight of the blue at whatever eroei we end up with is 10LJ. IE, if the eroei was only 1+1/10, then we would need to generate 100LJ of which 90LJ would be used to generate the next 100, and the remaining 10 goes to run the rest of the economy.

the world uses about 5x10^20 J / year.
assume current eroei of 9, society needs 4.5x10^20 J

It is the ratio of ERoEI to maximum energy scale which matters. Assuming the tar sands were economic at an eroei of 1.3, and other "limiting factors" were not a concern:
1 ton of tar sand gives 3,050,000,000J (2T = 1 barrel of oil)

eroei of 1.3 results in a total generation of 15x10^20J total needed, of which 10 would go straight to extracting more tar.
dividing by the 3e9 J/T
therefore 64x10^9 T of tar would need to be processed each year to run the world.

It isn't "impossible" to run the world on low ERoEI sources, it just requires an exponentially harder investment to pull it off, and as a result anything with even a slightly better ERoEI out-competes the lesser one and it isn't worth investing until the higher grade source can't meet demand.


Assuming the tar sands were economic at an eroei of 1.3, and other "limiting factors" were not a concern

... isn't assuming away other limiting factors assuming away sustainability?

If we need a simplifying assumption, assuming that other limiting factors are also consumed at a similarly high rate would seem more plausible.

For a discussion on "ENERGY" ignoring coal, nuclear, hydro and solar energy leaves a big gap.
While these only account for a small amount of the energy used in terms of Quads, electricity is X2 to X10 more efficiently used therefore provided a much larger proportion of "useful work".

Since most developed economies generate 20 to > 50% of their electricity using non FF and their are many opportunities to expand high EROEI( >50) hydro( especially small run of stream hydro), wind and solar, it seems more important to consider how present FF energy availability will constrain the development of these resources.

You value of EROEI for wind of 20:1 is getting out of date. These figures are valid for 100-500kW turbines but 2-5MW turbines appear to have an EROEI from 40-200:1 according to Mark Jacobson. At those values, financial payback is much more relevant than energy payback.

Neil - totally agree that other energy sources must be added to the chart. If you have any references to controlled studies for large hydro, coal and nuclear then I could add them to the chart.

In terms of wind ERoEI, as you point out when you get >>20, it becomes largely irrelevant - and finance takes over. If wind is soooooooo good, then it is a surprise to me why it is still struggling to take off really big time. The advantage of >>> ERoEI would be that significant amounts of the output could be used to mitigate intermittency.

I think what you are trying to say is that we have no shortage of high ERoEI sources, and back in my optimistic days I'd have agreed. The real issue for me at present is the persistence of government and industry to pursue ether low ERoEI sources (bio-fuels) or measures that reduce energy efficiency (H and CCS) - whilst claiming to have energy efficiency at the heart of energy policy.

However, wind is a limited resource and so should never be viewed as a complete alternative. It's not clear to me how much energy we can divert from the earth's natural energy systems without seeing unintended consequences. Even if the proportion is small I hope we don't assume that there are no negative effects. Unfortunately, most economies need to grow continuously (even though that's impossible) and so energy provision needs to grow to accommodate that.

We need a complete re-think of our societies and economies, not just a strategy for energy.

Both wind and solar energy resources are very large in relation to what energy is being used world-wide from FF burning. As far as diverting the earths natural systems, intercepting wind only slows down air speed within the height of a turbine, and only to a very small extent because turbines are spaced. Mountain ranges dramatically change low level wind speeds. The wind speed over the ocean and large bodies of water is much higher, due to the absence of mountains, trees( and wind turbines). If the ocean was completely covered in wind turbines this could influence climate(slightly) by changing atmosphere/ocean heat and moisture exchange.
Similarly for solar energy, on the land surface, ground, grass, rocks trees also absorb and re-radiate solar energy in a similar way to collectors but if we covered oceans with solar collectors would have a dramatic effect.
A rapid growth rate by an economy is only possible for a short time, but a slow growth rate can occur for a very very long time especially if the energy intensity declines faster than GDP growth, and the energy is from renewable sources.

This is the common perception but very little research is done to support this intuitive view. Many solutions, for example, seem to focus on very large scale installations rather than a scattering of small scale solutions but what would be the local environmental impact, which may have a domino effect to a wider area? My point is that we assume that diverting small amounts of the overall budget will have negligible effects. Wouldn't trying to figure out how to live sustainably be a better strategy?

But energy is not the only problem. A growing economy needs growing consumption of all sorts of resources. A focus on energy (with or without honest environmental impact assessments) is very narrow sighted. An assumption that low growth can continue for a very long time is an example of the kind of thinking that will ruin us or a future generation.

Good points sofistek. What is seldom acknowledged is that everything that is is doing something. Appropriating it to another use is going to have consequences. Oil in the ground is largely a placeholder. But oil also sequestered lots of carbon and releasing that has become a big problem. We need to remember that all the sun that is raining down on the planet and all the wind blowing across the planet are doing something. If we appropriate them in large measure we will have consequences. Until we do so in large measure we will likely not know what those consequences are. Perhaps they will be beneficial to humans, likely not.

I hate to say this, because it sounds suspiciously like what people used to say about the amount of CO2 we were emitting, but it's just really hard for me to see in such large systems how removing a bit of wind energy or solar radiation could make much of a difference.

In some reasonably small systems, like the water that flows under the Golden Gate Bridge, a colleague told me that removing the energy of the tidal flow via underwater turbines could cause build up of silt and other side effects. That seems to pass the "reasonableness test."

But total amounts of wind and solar energy seem, to me, to be too large to be affected by some windmills and solar collectors/panels.


You're probably right but the consequences of being wrong may put us on yet another track to mitigate yet another problem. Bear in mind that we are not just removing large amounts of energy, but we are putting it somewhere else.

I agree, that on it's face we would be removing such a small percentage that it won't matter, but we have changed our albedo by "only" 2% and we may already be in a runaway situation. Before someone jumps on me, I realize that the delta e in insolation increase is orders of magnitude larger, but we have been discovering that many subsystems can shift radically from small input changes.

I'm old enough to have a very healthy respect for the law of unintended consequences and despite some intensive studies lately, we really don't have a grip on the interactions in our system.

I like how oxidatedgem put it. "Everything is doing something"

Regardless of any real or perceived risks, we will do it anyway. That's our MO, so I guess we'll just find out.

For the want of a nail, a shoe was lost....

I agree, pragma. Aangel is probably right but, as he acknowledged, "it sounds suspiciously like what people used to say about the amount of CO2 we were emitting". Actually, that's exactly what I used to say. It seems incredible that removing a tiny percentage, even a fraction of a percentage could have any negative impact. But I don't think we know that and the impact may also depend on how and where we do it.

I'd love people here to concentrate on how we might organise societies and economies along sustainable lines, and not just by using the word. Richard Heinberg's distillation of the axioms of sustainability is a good guide to what sustainability means.

It's so disappointing, to me, that much discussion on forums such as this concentrate on ways to keep societies going much as they are, with little tweaks here and there, if only we change the power source.

Thanks sofistek, but sadly it appears to be more of a philosophical issue rather than a practical one.

It's so disappointing, to me, that much discussion on forums such as this concentrate on ways to keep societies going much as they are

I agree. My position is that we can't replace the energy that we consume, and even if we could, we won't.

Many others disagree. We are all on a sliding scale similar to the stages of grief. Many are still in denial, the technocopians are in the denial/negotiating phase, and that is just within the PO aware sphere. I think our only rational hope is to have as many people in the acceptance phase as soon as possible so we can make an orderly, or at least, less traumatic transition. I myself am still struggling with acceptance, even though my logical side sees rough times ahead.

I think you will find this video interesting. (2 parts)

The parts of the entire conference that have been posted to youtube so far are listed here:


Thanks sofistek, but sadly it appears to be more of a philosophical issue rather than a practical one.

Maybe I'm missing something, however it seems to me to be self evident that the current paradigm is physically unsustainable. By definition that means it will soon or already has reached its natural limits and will end, crash, c'est fini, R.I.P.

So what pray, could possibly be more PRACTICAL than to start down the road of radical change. Radical change will happen whether we discuss it and whether we want it or not, there is nothing philosophical about this, it is a fact of life, let's deal with it.

I'd like to quote from Jason Bradford's recent letter to President Obama.

Hope begins by facing the truth because decisions made in a state of denial are likely to be poor ones. Sometimes, truth is painful, and so hope may only arise through a path of disillusionment. Our country has been living in a state of denial for a long, long time, and now many are disillusioned. My question is: Will you lead a process of truth telling? Are we going to stop scapegoating and over-simplifying our troubles, and get to the core of our predicament? We may have to shed a lot of healing tears along the way, but people are waiting for this.

IMHO accepting reality is what we need to do, I no longer accept that we can't or won't because it is an unpopular notion. Reality doesn't give a rats ass about what we'd like, it just is. Accepting that we need new ideas to deal with this new reality can be quite cathartic.

We need to talk about what is practical, I would hope that this is the proper forum for at least a part of that dialogue.

Maybe I'm missing something,

No, you're not missing anything. It was probably poor phrasing on my part.

My point in the quote you posted was that whether our proposed "solutions" have any pitfalls of their own or not is moot. There are many people that have their own dog in the hunt or are panicking because we have left it too late that we will charge ahead with various silver bullets just as we have done so may times before.

I no longer accept that we can't or won't because it is an unpopular notion.

That's a nice sentiment, but from what I see and hear, you, I and most on this forum are in the vast minority. Until I hear the MSM and TPTB talk about true limits and living with one hell of a lot less we are screwed, because as I have said before, denial, hubris and greed will prevent any widespread mitigation.

We need to talk about what is practical, I would hope that this is the proper forum for at least a part of that dialogue.

I agree on both counts, but to the majority, the idea of giving up much of what we have "accomplished" isn't practical and therein lies the problem.

Jason says "people are waiting for this", which may be true, but few realize what "this" is.

Pragma, thanks for your clarifications.

Here's one from me:

Re: "I no longer accept that we can't or won't because it is an unpopular notion."

That's a nice sentiment, but from what I see and hear, you, I and most on this forum are in the vast minority.

My point was that we (all of us) will have radical change whether anyone wants it or not. It won't make any difference whether the people or those in power are in denial, we are already deep in transition. I agree that still only a small minority of us, understand how to make any sense of the writing on the wall.

I think of it like this; it's a beautiful day on the beach on some remote tropical island, the sun is shinning in the azure sky and the palm trees are gently swaying in the breeze.

However the birds have suddenly started flying towards the mountains and you can catch glimpses of other wild creatures heading up the slopes at the same time the tide is getting lower and lower and even though it is supposed to be high tide, there are fish that have been stranded, suddenly flopping around in shallow pools.

Whether the tourists on the beach believe what the old native islander has just told them, that this means a devastating tsunami is about to wash away the beach, doesn't matter at all to the tsunami, it is just going to roll up onto the Island and then roll right back out to sea again washing away everything in its path.

We can try to get to higher to higher ground by our own volition or we can be washed off the beach. Either way, we are not going to be sun bathing on the beach, however much we may want to or however unpopular the notion, that we have to pack up our beach towels and sunscreen and move. We are all going to be moving,(not just those of us in the vast minority as you say), and that is a fact.

Come gather 'round people
Wherever you roam
And admit that the waters
Around you have grown
And accept it that soon
You'll be drenched to the bone
If your time to you
Is worth savin'
Then you better start swimmin'
Or you'll sink like a stone
For the times they are a-changin'.

Bob Dylan

FMagyar, we're in sync, just from a slightly different perspective.

I'm frustrated because I'm the one that could get caught by the tsunami, trying to convince everyone else to run. Engineers tend to have a pathological drive to be proven right. :-) I guess it just goes with the territory.

As for Dylan, funny how a 45 year old song, which I fondly remember when it first came out, is still just as relevant (or even more so).


Yep! :-)

I used this simple description a long time ago but it still works. An imponderably immense flow of sand is raining down incessantly upon a fulcrum and splitting evenly into the pans hanging below it. We are insignificantly small as we randomly move these grains of sand about and have no effect upon the sands distribution...until we start to whittle on the fulcrum. We barely nick it but the increased flow of sand to one side wears it faster on that side...our little nick isn't little anymore. So much for the balance we had thrived in.

Solar energy is that sand and we keep whittling the fulcrum, it would be great if we managed to whittle it back the other way and get it to balance out again, but.....we are way too close to the fulcrum to have any perspective on which way that would be. We will keep whittling none the less.

The problem with arguing by analogy is that unless its a homology, the argument does not actually hold.

The direct question is what stress is being placed on living ecosystems. If there is stress, the simply answer is, "don't do that", pick an energy source that does not place discernible stress on living ecosystems, as that is our life support system and we will know that we have taxed it beyond the ability to recover when we are trying to use it for life support and are failing ... which is a little late for regrets.

It would, of course, be insanity to adopt anything as the sole and solitary answer, and indeed it would be insanity to refrain from expanding wind power which will substantially undermine the economics of coal power generation when we know how serious the problems with coal power generation are. Its like refusing to get an emergency appendectomy because you are worried about the risk of the incision becoming infected.

Actually I left the scariest part of the analogy out, once the sand stream causes enough wear to one side of the fulcrum we cannot ever harness enough energy to whittle it back to the location that balances the system flow to what it was before we started messing with it.

I know this is an oversimplification, especially for people who frequent this site, but this analogy is a simple useful tool. Many, many can't see how anything little old humankind can do can permanently affect so large a system with such a huge near constant energy input. Feedback loops, new pans and all sorts of other things can make it a better analogy, but the idea is just to broadcast a simple to grasp image of the endless huge flow of sand hitting the point of cone and distributing into suspended balancing pans (use as many pans as you like). If you somehow slightly distort the cone the sand flow does the heavy lifting that alters its own stupendous flow and that moves the pans out of balance. Just a simple easily grasped visual nothing more.

Back in the early 70's, when I first used this aid, the whole idea of permanent human caused change to the big system was much more heretical than it is now. Carbon release appears to be the big knife whittling the fulcrum, it is just we can't completly discount what any other massive endevour of ours could catalyze. For some reason the one that scares me most of the renewables is thermal. The likelihood of our cooling the mantle enough to make a difference is probably very remote it is just we have no clue what any cooling of it could be bring about. Still we have a real good idea of what more carbon release will do and all the renewable alternatives appear to be better than that.

"it would be insanity to refrain from expanding wind power which will substantially undermine the economics of coal power generation when we know how serious the problems with coal power generation are"

Yes, but let's hope that expanding wind power is done with the assumption that, no matter how little or how much energy we extract from the wind, the environmental effects will be negligible.

I'd much rather we figured out how to live with less electricity, instead of trying to replace one energy source with another (and then expanding the total energy availability). It may be better for our environment to shut down a coal fired power station and not replace it, than to replace it with a wind farm (even though I'm a wind farm supporter).

The study published in 2006 can be downleaded here

The study is basically saying that there is a very large small hydro(1-30MW) potential in most US states(300,000MWa) and excluding federal lands, and remote locations and only harnessing 50% of stream flows without using dams, could have additional 30,000MWa production.
Large hydro also has considerable potential to be increased(perhaps 21,000 MW but this was not the scope of the study).
The study did not consider the cost of developing these sites except only considered sites within 1 mile of a road/ or existing grid infrastructure.
Canada also seems to have a lot of additional potential large and small hydro( 166,000MW by another estimate).

Your comment about why wind power is "struggling", growth rates of 25-50% per year indicate that the struggle is to expand manufacturing capacity and skills.

I would agree with you about low EROEI of ethanol,and other bio-fuels, but one way of looking at this is that's part of the adjustment to a shortage of liquid fuels. If we eventually have stacks of non FF electricity, it won't matter if ethanol uses as much electrical energy in its production as it contains, it would be a way of still flying aircraft without using any FF.

If wind is soooooooo good, then it is a surprise to me why it is still struggling to take off really big time.


Private investment follows public investment. There exist enormous public subsidies for oil, coal, gas and nuclear. Subsidies for wind, solar and the like are considerable less.

In Australia each year we have,

Fossil fuel consumption subsidies, $9,300-$10,100 million up from about $8,900 million a few years ago
Renewable subsidies, $313-$334 million
[source 1], [source 2]

Feed one guy 10,000 calories a day, and feed another one 330 calories, one will get fat and the other one will get thin. You might want to blame their different metabolisms, but in the end... 10,000 calories vs 330 calories utterly dwarfs any difference in their metabolisms. Put them on 2,000 calories each and then we'll see what they're like.

Judging by the weight of the subsidies, fossil fuels are not commercially viable compared to renewables. In fact, it's remarkable how well renewables do given their relative lack of support.

Incidentally, for $10 billion you could buy something like [source] 7,700 x 1.65MW wind turbines, each of which would produce about 5.6GWh annually (obviously depending on placement), thus the $10 billion would give us 43,120GWh. Australia produces about 220,000GWh in total. So the $10 billion - one year's fossil fuel subsidies - could convert one-sixth of Australia's electricity generation to wind. The Danes and Spaniards manage more than that renewable penetration, so it must be technically feasible.

Of course spending $10 billion of public funds on wind power would be a vile and disgusting interference in the free market. Whereas spending $10 billion of public funds on encouraging fossil fuel consumption is... um...

Of course spending $10 billion of public funds on wind power would be a vile and disgusting interference in the free market.

Of course the bankers and the good folks on Wall Street would never accept something like a multi billion dollar bailout, because even though they need their bonuses, it goes against their fundamental beliefs in the markets, and they could never live with that, it just goes against their principals.

"Private investment follows public investment. There exist enormous public subsidies for oil, coal, gas and nuclear. Subsidies for wind, solar and the like are considerable less."

This is simply untrue in the US. Subsidies for gas and oil are very high...but *new* nuclear, solar and wind receive the *exact* same subsidy, except for nuclear it is for only the first 8GWs then it ends under current PTC legislation. Wind and solar subs go one...for the life of the equipment and have no upper limit.


I did a post recently on a paper Dr. Gilbert Metcalf of Tufts University that was an attempt to compare effective tax rates for different types of energy. This is his summary table, showing renewables and nuclear are all treated well, compared to fossil fuels.

The reason that nuclear comes out as well as it does is because of recent legislation that will give tax benefit to only a few plants.

Euan: In terms of wind ERoEI, as you point out when you get >>20, it becomes largely irrelevant - and finance takes over. If wind is soooooooo good, then it is a surprise to me why it is still struggling to take off really big time. The advantage of >>> ERoEI would be that significant amounts of the output could be used to mitigate intermittency.

Here is my thinking:

First, wind is competing with coal and coal still has a fairly high EROEI (in the US).

A. Two energy sources will have the same cost when their energy inputs (quality adjusted) are the same. So wind will have the same cost as coal when both have the same EROEI.

B. An existing energy source will have a major subsidy to it's transportation and distribution system from past energy investment. Coal generated electricity has likely paid off power lines, power plant, rail ways, road systems, etc. Only the maintenance cost on these items is being factored in. Wind must build all of these things new and pay the energy cost of them.

C. Growth. Above and beyond all the input costs, if wind is going to grow, the cost of that growth must be added. Say we have a 10:1 EROEI energy source. We want 10% of the power redirected into growth. That drops it to a 5:1 source when comparing power prices. Clearly, any power source trying to grow is going to be at a penalty to a power source that does not try to grow.

So to get alternatives to grow in a free market requires the following:

Alternative Energy In + Supporting Infrastructure + Growth Requirement <= Existing Fossil Energy In

What this says to me is that the free market will never even try to replace a fossil source with a new source until the fossil source is falling down the energy cliff. And then how much time is left? Not enough.

Notice how badly growth chops down the EROEI. If the minimum EROEI is, for nice round numbers sake, 10:1 and we have a 20:1 power source. We can't divert more than 5% of the net energy into growth or we push the power source below 10:1.

We can expect that the current Wind growth rates of 20% - 50% to slow way back as fossil net declines and less surplus exists to direct into growth.

A. Two energy sources will have the same cost when their energy inputs (quality adjusted) are the same. So wind will have the same cost as coal when both have the same EROEI.

This statment is incorrect. I will illustrate this claim by using the example of another resource than energy. Suppose we had oodles of energy but limited supplies of water, so that water was the limiting factor of production. We would then be willing to spend lots of energy and other resources recyling waste water. Let us further suppose that the process of purifying waste water requires the input of some amount of fresh water.

All other things being equal that purification process which had the smallest input requirements of water would have the highest economic quality. However, the measure of that quality would not be the ratio of the output to the input. If a purification process with output/input ratio = 2 was replaced by a process with no requirement for water input at all (and all other inputs identical), the economic quality would increase by a factor of 2, not by a factor of infinity.

Furthermore, a claim that a lower water input relative to a given output implies lower total cost would be true only if the value of the excess water production is overwhelmingly greater than excess costs of other production resources used in the purification process.

Even in zeroth order the value of any kind of economic output depends on the cost of all of the required inputs.

Of course in the world of energy production it is generally true that higher energy inputs relative to a given output imply higher inputs of other resources. For example not only does it take more energy to produce a barrel of oil from oil shale than from conventional oil fields, but it also requires more labor and more fresh water.

The ratio of net energy output (as opposed to gross output) to energy input can be turned into an economic figure of merit if some assumption is made about how the costs of non-energy inputs to the production process scale with input energy. Without explicitly making these assumptions the claim that the use of EROEI creates an objective basis for analyzing energy production economics is nonsense.

It is not nonsense. It is just not as complete as it could be.

You are right to point out that resource limitations could skew the results, especially as a process tries to scale. That is the root of the problem with fossil fuels. As we try to scale them, the EROEI declines. If tar sands required more water than the river could provide, then the EROEI would need to include the building of water pipelines from other areas (possibly at a crushing energy cost).

There are also financial biases that I did not mention. Almost all the energy input of wind power is contained in the initial construction, thus interest must be paid on the whole Energy Input side for wind. Coal and natural gas plants have much lower construction costs but pay fuel costs as they operate. This allows them to partly fund out of cash flow and avoid that large interest penalty.

I am sure we can think up many others. Subsidies. Regulation of pollutants etc.

It is not nonsense. It is just not as complete as it could be.

Suppose we have three different renewable energy sources with the same installed gross output capacity in terms of kWh/year, one with EROEI=20, one with EROEI=10 and the other with EROEI=2. I will ignore the payback time issue which is irrelevant in long term equlibrium but is important during a growth phase as you have noted. Every time the first energy source delivers 0.95 units of net energy the second energy source delivers 0.9 units of net energy and the third source delivers 0.5 units of net energy. Please explain why EROEI is a measure of the relative energy quality of these three sources.

EROEI isn't a measure of energy quality. I think we are talking past one another or I missed the point of your water example.

When I talk about energy quality I mean how useful is that source of energy. There have been several attempts to define a quality comparison between energy sources. Ayers uses exergy. Cleveland tried several in "Aggregation and the role of energy in the economy", 2000, Ecological Economics.


Methods for investigating the role of energy in the economy involve aggregating different energy flows. A variety
of methods have been proposed, but none has received universal acceptance. This paper shows that the method of
aggregation has crucial effects on the results of the analysis. We review the principal assumptions and methods for
aggregating energy flows: the basic heat equivalents approach, economic approaches using prices or marginal product
for aggregation, emergy analysis, and thermodynamic approaches such as exergy. We argue that economic approaches
such as the index or marginal product method are superior because they account for differences in quality
among fuels. We apply various economic approaches in three case studies in the US economy.

I can send you a copy if you like (send me an email). We agree that simple energy in vs energy out is not enough. Some kind of weighting of factors would improve the analysis. But if the mix of energy used by the two energy sources you want to compare is nearly the same, it won't matter much.

Electric energy is not at all efficiently used, as the total consumption must include standby modes. This is underestimated.
According to a EU study standby consumption accounts for 30% of total consumption. This is not much different from energy loss of poorly insulated homes.
The EROEI of standard 2 MW wind turbines is in average a bit above 120:1 so it is an entirely economical i.e. financial issue ROI and time to return of investment and these figures providee good support for wind energy.

The graph is P = 100(E-1)/E for 50>E>1. I don't think E around 10 has special significance. It may be furthest from the origin though that is an artefact of scaling.

I would ask what separates the modern middle class lifestyle from the Neolithic. Those guys had food and shelter and clothing sort of. They didn't have electricity, cars, refigeration, insurance, contraception, tuxedos, antibiotics and electronic entertainment like blogs. That could be the difference between a 10+ lifestyle and a 2 lifestyle.

That pretty well sums things up. You need to add modern agriculture to your list. What is the carrying capacity for hunter gatherers?

Returning to optimistic mode, there is likely no shortage of high ERoEI energy sources - its a simple matter for our policy makers to learn this simple point and to adapt policy accordingly.

But no matter what, the issue of population growth has to be addressed. Heading for 7 billion and counting, quite simply can't go on for ever.

What is the carrying capacity for hunter gatherers?

Of course, in the worst case scenario, we'll likely find out again.

On a different track, while not exactly what you meant, this image came to mind about carrying capacity for hunters...

Euan -
your guess as to the range of Eroei for temperate biofuels is way off, given that you don't specify any particular form.
I'd therefore outline a best case for the major biofuel now in use, namely firewood.

When I bring a wain-load of dry oak limbs down from the coppices here,
and log them with an electric chainsaw powered by the micro-hydro turbine on the brook,
and then wheelbarrow the logs to the modern woodstove that heats the farmhouse,
my energy outgoings are miniscule.

Allowing half a day's food & pony fodder for a tonne of dry oak in the stove,
which at 70%(e) x 4,950 KWHrs/T = 3,465 KWHrs delivered
implies an Eroei far over 100:1.

The production of methanol from temperate coppice will not yield as high an Eroei as firewood,
given the energy embodied in the plant, but I'd expect it to be well above 30,
given that the reaction is exothermic (meaning there is no net heat input)
and given a rational modest refinery scale and consequently sustainable feedstock collection technology.



With intermittency I wonder if we should weight by capacity factors. For example an EROEI of 20 with a c.f. of 35% gets a weighted value of 7. That no longer makes the cut of 10.

If we only had good data it would be interesting to perform logarithmic regressions of world GDP against (E-10) to see if it has a good fit. Key data points would be the start of the Industrial Age (use of coal) and the start of the Oil Age. I suspect population grew to complement the possibilities offered by leaps in EROEI. While real GDP will probably follow downsteps in EROEI that's not so easy for population.

Prediction; soon we'll stop talking about GDP and focus on 'spiritual wellbeing'.

W.R.T. volatility of energy ... "intermittency" in the common parlance, even though the wind is blowing somewhere and the sun is shining somewhere ... the answer to the question:

With intermittency I wonder if we should weight by capacity factors. For example an EROEI of 20 with a c.f. of 35% gets a weighted value of 7. That no longer makes the cut of 10.

... the answer is no, we shouldn't.

Multiplying ERoEI by the capacity factor is:

Energy produced / Energy consumed to produce it


Energy produced / Maximum peak production capacity


(Energy Produced)2
÷ [(Energy consumed to produce it)×(Maximum peak production capacity)]

... which does not seem like it would have any useful interpretation.

The yellow arrow, pointing to ERoEI = 9 is intended to provoke some debate since we do not know with any certainty what the minimum ERoEI for modern industrial civilisation is.

Obviously we cannot give an exact figure for this. My take, at a qualitative level, is "how hierarchical a society can a given EROEI support?".

By this I mean, to sustain a given energy input into society we need as a minimum a sufficiently educated workforce to understand the problem and have the technical skills to build and maintain the energy infrastructure that provides the energy. At the bottom end of the scale, a hunter gatherer society in ecological equilibrium with it's environment will have an EROEI of about 1.0. The tribal unit has just enough energy to sustain it's own existence. If they get a bit better at hunting (sustainably) then they will increase the population of the tribe until the new technology is offset by a natural reduction in the food supply to balance the EROEI back down to one. If the food supply falls further, a few people will starve or die of hunger related conditions and the balance is restored.

Agriculture, civilization, education, writing, science and fossil fuels etc. have each in turn shifted the EROEI of societies ever higher, allowing more and more people to spend their time in less directly productive (producing energy for human consumption) activities like teaching, religion, being king, etc. This provided a positive feedback accelerating the social EROEI until we get to our current state, where (in the developed world) only a tiny fraction of people are involved in (energy and food) production.

However, this giant jolt has left societies completely out of balance. We have yet to change human nature through social control or education to limit our instinct to reproduce. Global population has steadily risen as a response to the increasing EROEI but as yet has not caught up with the supply of cheap energy. That is about to change as the supply of energy starts to fall. The positive feedbacks from the increasing energy in society are grinding to halt, and may even have started reversing. We need to spend a large percentage of our available human capital educating and training the next generation of scientists, engineers and farmers (and teachers) to be ready to replace the existing stock when they retire. As the overall EROEI falls as the supply of cheap fossil fuels falls (and the supply per capita falls faster) we will need to train an ever higher percentage of our people for longer before they become productively useful in this role. If we all lived forever, this would be easy, but life expectancy (and productive lifespan) will not continue to increase. All around us, we are hitting limits to growth, and we are inevitably facing a population overshoot.

How much of an overshoot is very hard to define. About half the population of the planet still lives on $2 a day or less. (exact figure depends on the fiat value of the dollar). This is a subsistence level not so different (if not worse) than that of a hunter gatherer society. We have NOT improved at a species level since then in total population terms, we have simply become more hierarchical. Inevitably, most of the population overshoot will be among that 50% of the global population. The question is, how far back down the pyramid of education levels will we fall before we are (perhaps for the first time in 10,000 years) in a sustainable society? We could fall a very long way. If the Taliban ever got control of world government, we would be back at the stone age in two generations. When the Roman empire contracted away from British shores, social complexity here collapsed back by maybe a thousand years of development in a similar period.

We need to box clever to sustain what we can. There is very little evidence of us doing that.

As I said in Freezing Point, rather than EROEI as such, what's important is the relative affordability of resources and labour.

When resources are cheap and labour is expensive, we have combine harvesters, etc. When resources are expensive and labour cheap, we have peasants in the fields with hoes.

I mean, why don't we have rickshaws in the West? Because the cost of labour of someone pulling the thing for a day is so much greater than the cost of fuel for a vehicle for a day.

If resources become more scarce, they become more expensive. If they become expensive compared to labour, then labour starts stepping in where we once used resources. If petrol is $100 a litre and labour is $100 a day then rickshaws look pretty good. But a society with lots of rickshaws is not a truly industrial society - though it may be partly industrial, see India and China.

When resources are scarce, it's unlikely they'll be equally scarce for all. Much more likely is a growth of the rich-poor gap - some people will have some resources, most people will have almost none. Which makes rickshaws even more likely, since labour will cost much less than $100 a day.

EROEI can be an expression of these issues, but is not the issue itself, I think. The issue is the relative affordability of resources and labour.

Which is why I want us to get off these declining resources. It doesn't matter if they run short if we're not burning them.

This overlooks the basic point of this posting - Labour will keep on getting cheaper in real terms until the price of labour is insufficient to keep up the supply. In physical terms, wages for unskilled labour fall until they fall below a starvation wage for the labourer and his/her family. At that point the supply starts to decline- people start starving to death. Given that half the planet is already close to that level of income, it will not take much of a decline in total energy/food for significant numbers to start falling below that level. The alternative is that the level of hierarchy (social complexity) declines - the pyramid of wealth (as measured by per capita energy consumption) flattens. In fact, both will inevitably happen at the same time. The problem is as the pyramid flattens, the amount of energy that a simplified society can produce falls as well (research into fusion will be abandoned. New nuclear build will be abandoned, existing nuclear will be abandoned etc. etc.) in a negative feedback spiral until a new equilibrium is reached.

This overlooks the basic point of this posting - Labour will keep on getting cheaper in real terms until the price of labour is insufficient to keep up the supply.

Will it? Why?

Amidst the EROEI and Olduvai doomers, there are a lot of things like this that are simply stated as being self-evident. They're not. Explain.

Ok, I'll bite.

It's not self-evident that millions of people will have skills for a failing economy and will find no employment offers?

Oh? Is the economy failing? Not here Down Under, at least not to the extent of the US.

Are we talking about the US banking crisis today, or about peak fossil fuels in the future? They're different things. Economic crises existed long before resource depletion became an issue. A housing bubble, an unregulated financial sector and a big old Ponzi scheme have not much to do with EROEI.

I thought we were talking about EROEI?

We need to spend a large percentage of our available human capital educating and training the next generation of scientists, engineers and farmers (and teachers) to be ready to replace the existing stock when they retire. As the overall EROEI falls as the supply of cheap fossil fuels falls (and the supply per capita falls faster) we will need to train an ever higher percentage of our people for longer before they become productively useful in this role. If we all lived forever, this would be easy, but life expectancy (and productive lifespan) will not continue to increase.

If the return on a year of schooling (note that I don't say education) is too low, we will eventually run out of resources for schools.  How to improve that return?  The "easy" (if Politically Incorrect in the extreme) answer to this is... improve the human animal.

People differ greatly in their ability to absorb knowledge and develop useful skills.  At the low end, some people may never be able to live independently; at the high end, some are capable of doing college-level work in their early teens.

At least part of this difference is due to genetics, culture or some combination thereof.  Ashkenazim have an average IQ of around 110, which is a serious improvement over the caucasian average of 100 and corresponds to a large decrease in required schooling for a given level of achievement.

As Randall Parker notes frequently, genetic sequencing is already showing us where the "smart genes" are and how they interact.  Sooner or later we are going to have very good information on:

  • Which gene combinations from any two parents will yield greater or lesser intelligence.
  • What the liabilities of these genes are.

Psychological and behavioral research will tell us something about what kind of upbringing develops or stunts the growth of intelligence from the underlying genotype.

Imagine that parents used widespread IVF and PIGD to cut off 90% of the intelligence bell-curve below 90 IQ and try to avoid the health penalty from some of the more troublesome high-IQ combinations.  The return on good schooling would skyrocket, and it would be much easier to get good schooling because the low end of the SAT score curve (from which a large fraction of teaching majors come) would be much, much smaller.  Why would anyone go for this?  All you'd have to do is pay for it; parents usually want the best for their children.

This sort of thing correctly went out of fashion in 1945. I hope it stays that way

This sort of thing correctly went out of fashion in 1945. I hope it stays that way

I don't recall that comment mentioning anything about a "thousand-year reich", or the alleged inherent superiority of whites vs. non-whites.

Regardless of the tragic origins of its long discredited uncle, eugenics, modern genetics holds a great deal of promise for ridding humanity of the scourge of its most persistent inheritable diseases, not to mention the possbility of regrowing severed limbs and failed organs at will, reversing blindness/deafness, curing autism, inhibiting age-related diseases, etc. Whether or not "improving" humanity through genetic engineering and/or artificial selection is a good idea ethically, it's coming. There's no putting that geneie back in the bottle, nor telling the disabled and dying that we refuse to even *try* to cure them on moral grounds.

I have worked on the human genome project. You clearly have not. It has been estimated that every human being has teo or three (out of about 24000 human genes) recessive 'disease' genes, which are only expressed when both parents share the same gene varient. My parents shared one such gene. My brother died. If I were to have a child (unlikely now) it would have a one in 2,400 of suffering the same way. To remove all 'diesease' genes by simple embryo selection is simply impossible.
Selecting genes for intelligence is also far beyond anything we have any hope of doing in the foreseeable future. Given our current understanding of what 'intelligence' is, that is just as well. At least 50% of what we call intelligence is thought to be environmental, not genetic.

'Curing' genetic conditions by direct injection of corrective DNA by viral infection was tried about 12 years ago. One patient was cured, one was killed. The project was dropped, I'm not aware that it has been tried again.

Look at what we have acheived with pedigree dog breeds if you want to know how not to do genetic selection.

Understanding genetics has enabled us to do wonders in medicine and predicting genetic conditions, but it has so far 'cured' nothing that I am aware of.

I have muscualr dystrophy - it's a single gene locus fault - given the choice of leaving that fault in or out it would take a spectactularly naieve and politically correct idiot to vote to leave it in 'for ethical reasons'. So I have to play roulette with my children - long odds yes but there none the less. We have the mucal fold test or maybe we shouldn't have ?!
"I have worked on the human genome project. You clearly have not"
I hate people who try and bluster their scientific credentials when by doing so they are , ironically, being unscientific.
No progress with viral therapy means no possibility of future progress, right ? God help us.
Obviously we'll never understand phenotpyes and protein folding. Fine - that's your opinion - you go off and have disabled children and look them in the eye later and say you did the right thing.
I could say far far ruder things but i'll restrict myself to just syaing "idiot".

He DID acknowledge the knowledge gained from genetic advances, and didn't say it should be abolished.. he was responding to the direction the conversation was heading, which was the clear MISapplication of Genetics to mark so-called Gene-derived 'Intelligence'..

Where Engineer-Poet had offered this line..
" - Which gene combinations from any two parents will yield greater or lesser intelligence. "

The shadows of Eugenics didn't need to be explicit..

Well it doesn't read that way. He is implying that we shouldn't attempt to select embryos on grounds of genetic deformity as they may unknown consequences for the genetic variation of the species.
We may not be able to redicate all disease genes but if he is seriously saying that disabled or seriosuly at risk babies should go ahead and be born anyway the he is clearly nuts.
And the arrogance of the "I'm an expert in X therefore any statement by you is false" is so unfuriating.

The shadows of Eugenics didn't need to be explicit.

If we never challenge taboos, they will continue to dictate what we can and cannot talk about.  Since I'm an iconoclast, I choose to push the boundaries (in this area and others).

Because of the HGP and other efforts, we already have a huge amount of information on the genes associated with cancer, heart disease, auto-immune disorders, metabolic problems... and intelligence.  People are already using PIGD to make certain that their offspring will not have a variety of diseases.  It's not a big stretch to test a bunch of cells for alleles known to influence intelligence (and related things, like impulsivity) and pick the best.

The spectre of a certain regime only rears its ugly head when Government decides who is allowed to have children.  That's not necessary.  In the long term, these techniques will become so cheap everyone will use them; in the short term, government can use the offer of free PIGD to everyone to reduce its own costs.  The effort will pay for itself many times over; imagine what it would mean if there was a large reduction in autism, hereditary retardation, and a general boost in IQ.  The payoffs would start with reduced costs for various treatments and special ed. before the first cohort reached the age of 5, and more benefit for a given amount of education for decades thereafter.

I also note that RalphW was mighty quick to Godwin the topic, while failing to acknowledge that the rich will probably be doing this on their own behalf in the near future.  I think the Gini coefficient of the USA is far enough out of whack without the effects of another large increase in the average intelligence of the wealthy through the reduction of regression to the mean.

One thing I think government should be allowed to have a hand in selecting against is sociopathy.  The rich may want it to help them get richer... but I think we've seen just how much damage it can do.

I understand your goal to try to make the human animal more fit to live here. Of course humans are a social creature so the balance of genetic structures to best compliment one another and the construct the most bullet proof society aiming at whatever end goals some committee or despot come up with will have to be considered paramount before any such program were universally implemented.

It sounds like a free market approach is more what you are looking for, so every corporation would have a pony in the show and the competition could get ugly. All the stuff of sci-fi I know. Old Aldous Huxley's vision of this was popular in my day. 'Brave New World' isn't a bad post adolescent read.

Our arrogance is generally our downfall, assuming our short run outlook will quickly construct a being more suited to life than the long run natural selection process (not often friendly and oh so slow) is the height of arrogance. But we will tinker and some of those who can afford will certainly try to give their get a better shot at inclusion in the ruling aristocracy.

Genetic work and reconstruction will have some place in our march, but going for something like IQ improvement is very likely one of the worst things we can do with the manipulation of our new handle on an incomprehensively powerful new tool. This is an area where we must truly go slow, because any thing we call slow will still be lightning fast in the grand scheme of things.

"This is an area where we must truly go slow, because any thing we call slow will still be lightning
fast in the grand scheme of things."

Yes indeed.

Really, eugenics is jumping the gun, when there is so very much fine and necessary (and safer)
work to be done in the realms of euphenics and euthenics.

Considering that the human animal has been doing eugenics for as long as we've existed (mate selection), I have to laugh at you.

Making it more certain and more available so everyone can have the benefit... that's worth working for.

I don't have to laugh at you, even though the same is true of euphenics and euthenics.

Making it more available so everyone can have the benefit is of course very important,
and a large part of the reason why it ought not be hurried. The benefits of high-tech
eugenics are generations away from most people on earth. But the benefits of cheap,
low-tech euphenics can be had by all within a few decades. First things first.

For one example, the ensurance of adequate iodine alone can, for a pittance, increase
population I.Q.s dramatically within a generation. This would add many billions of
I.Q. points to our collective reserve -- a terrific boon. Those are I.Q. points that
we need for all reasons, not least to plan, intelligently and wisely, our eugenic
programs of the future.

First things first. Low-hanging fruit first.

True.  For instance, India could improve its collective intelligence using iodized salt.

However, salt in India is produced by cottage industry, and effective control over iodine levels appears to be politically impossible.

Getting past the entrenched interests... that's the fun part.  There aren't any big entrenched interests in PIGD in most of the west (the Roman Catholic Church's blanket opposition to any tampering notwithstanding), so the barriers appear to be technical and financial only.

The West IS a big entrenched interest.

If the return on a year of schooling (note that I don't say education) is too low, we will eventually run out of resources for schools. How to improve that return? The "easy" (if Politically Incorrect in the extreme) answer to this is... improve the human animal.

Another way, equally PC incorrect, would be to stop sending everyone to school. Tainter discusses the diminishing returns of education as more and more less well qualified students pursue "advanced" education.

cfm in Gray, ME

The deluded british government set a target to get 50% of the population into higher education. How you can set a target is anyone's guess. I would assume the intelligence distribution curve today is the same as it has always been. The result is the value of the degree is diluted and we have people with degrees either not qualified to use them or the qualifications are of a type that can realistically add no value to society. Sorry I am being politically incorrect as well.

Imagine that parents used widespread IVF and PIGD to cut off 90% of the intelligence bell-curve below 90 IQ and try to avoid the health penalty from some of the more troublesome high-IQ combinations. The return on good schooling would skyrocket

I wonder what would happen to ambition and resource use....

It seems like one almost needs to look at electricity generation separately--in addition to this kind of analysis.

Natural gas can be burned directly for heat, or it can be converted to electricity. I would expect EROEI calculations would be done on burning natural gas for heat basis.

For electricity, it seems like what one wants is something akin to unsubsidized total cost of delivery to customers for each of the various fuels available. If major grid upgrades are required, this needs to be part of the unsubsidized total cost too. Someone may be able to convert these numbers back to EROEI numbers as well, but they would not be directly comparable to standard EROEI calculations.

In our dysfunctional society here in the UK a lot of people effectively burn natural gas in a power station to convert it to electricity which is then used to heat their hopelessly under-insulated homes to above-summer temperatures 24 hours a day. Of course they complain about the price, and spend hours comparing different companiy web sites for that elusive 'cheaper contract' that our government tells us we deserve from the free market in domestic energy supplies. And we have a charging regime where people who consume less pay more per unit energy than the energy hogs.


And we have a charging regime where people who consume less pay more per unit energy than the energy hogs.

Are you referring to the con trick that the "standing charge" was dropped so that people who don't use electricity don't pay a standing charge. The price was then increased so dramatically of the first few units (kWhr)used that unless you disconnected the supply it was virtually impossible to avoid paying it (the standing charge equivalent). You are "bang on" and when I tried to explain this "con" to British gas the guy failed to see my logic. I got nowhere, just some pleasure pissing the guy off!

No - this conflates efficiency of supply and efficiency of demand. Natural gas, oil and coal EROI numbers are at the wellhead. How efficiently we use them is a different (and important) issue. But in order to accurately know what our fossil energy capital is vs our renewable 'interest' we have to know our energy budget, annual and total.

If it turns out that the consumption efficiency when COMBINED with a low supply efficiency (EROI) of a social system can't be maintained, then we need to work towards changing either, or both. But I think we have to recognize each component before saying 'electricity' is low EROI from nat gas. That way we can put our energy capital to its highest use (nat gas for heat and plastics, etc.)

It is complicated no doubt. As complicated as Black Scholes option models or leveraged options on credit default swap baskets? More so I think. But at least it will attempt to measure things in physical terms.

Part of the problem of calculating EI is that by and large oil energy has created electric energy - whether in building damns, building windmills, building solar panels (including mining, refining, and forging the materials as well as building and maintaining the roads to supply them). It doesn't matter what the base ERoEI of windmills are if electricity cannot build and maintain roads. Without roads there is no grid, no transport of materials from far away. We are back to building windmills from wood for pumping water, if we can find any good wood that is. Of course all the raw materials that come from across the ocean are going to require wind propelled ships to obtain once oil is gone. An then there is the energy to continue to steal these resources from other countries for far less than they are worth and to continue to enslave poor workers to mine them.

I keep getting amazed that folks are still thinking that somehow windmills and solar panels will save the day and we don't have to face TEOTWAKI. I think brains have been scrambled by windmills or ooked by solar panels. In the process of building the good life based on oil, we have depleted our old growth forests, our aquifers, our soil, our phosphorus, our ability to dump waste into the skies, our wild fauna. We haven't noticed this because we have used oil to create other building materials, to forge our metals, to pump water from deeper and deeper wells, to mine phosphorus from farther away, to process metals from ever poorer sources, to supplement our depleted soils. We have used it to create alternative sources of energy and then not counted all the EI so we can get a high ERoEI that looks good on paper. We have used previous excess oil to build infrastructure, but have stopped doing full maintenance (perhaps that is helping to cover the lower ERoEI of our fossil fuels). When we can no longer get the oil we go back farther than where we started at the beginning of the oil age. Since we have more of one thing, people, we will go back with a huge crash.

I keep getting amazed that folks are still thinking that somehow windmills and solar panels will save the day and we don't have to face TEOTWAKI.

Generally, "TEOTWAKI" as "the end of the world as we know it" is taken to mean an apocalyptic and bad change. Unless they're joking, people don't usually say, "I'm getting married, it's the end of the world as I know it," or "I got a new job, it's..." and so on.

So I'll assume you mean that we're facing an apocalyptically bad change. I disagree, but let's take it as given for the moment.

My response is that we may be able to avoid it by determined action, or we may not be. Windmills and solar panels may save us from it, or they may not. But there is no harm in trying. It is better to flail wildly screaming than slip under the waves without a murmur. Better to swim. Best to build a new boat. Which we're able to do, we don't know - all we can do is try it and see.

In the process of building the good life based on oil, we have depleted our old growth forests, our aquifers, our soil, our phosphorus, our ability to dump waste into the skies, our wild fauna.

Forests can be and have been replanted. This along with conservation can renew aquifers. Soils can be revived by good husbandry of the land. Phosphorus does not disappear when used like burning fossil fuels, but is simply dispersed, so that again with good husbandry of the land we can use it without dispersing it. And so on.

To say that we need to build renewable energy generation is not to say that there is nothing else we need to do. We can do all these things. For example, I buy wind-generated electricity from my retailer, and I am a guerilla gardener of trees. I do two things at once, amazing, someone might make me an honorary woman if I'm lucky!

This does not mean that doing these things is easy, or even that in doing them we are certain of success. Trying may lead to miserable failure. Not trying will certainly lead to miserable failure. I'll take possible failure over certain failure any day.

I agree ...

What could one person do with 5 acres , 1 acre, or whatever .... given ....

a well with solar pv water pump and a passive solar dwelling and wood lot if needed ????

Instead of "40 acres and a mule", "1 acre and a solar PV pump". If it's a good passive solar home, two acres - including the wood lot - would be enough so that someone or some family could live a "half-farmer" life. No travel, no car. A different head.

cfm in Gray, ME on 2 acres

Kiashu by saying the end of the world as we know it I mean just that - the end of industrial civilization. Most people consider that to be a disaster of immense proportions. Third worlder miners who die early deaths in order to mine some of the resources for our industrial civilization such as copper (average life of a South American Copper Miner is 45 years) might not find the end of industrial civilization to be as big a disaster as your average American.

Phosphorus, if washed to the ocean as much of our fertilizer does is lost for all intents and purposes.

Soils are not always able to be revived in time frames that are useful to current population. Reviving the requires organic matter which has to be borrowed from some other area of the planet. I add leaves to my cotton farm depleted soil. They don't magically appear. They are raked by homeowners in town who are thereby depriving their yards of the organic matter they may some day wish they had. Climate change and deforestation turn some areas into deserts. Once fertile lands in Mesopotamia are still deserts today.

To date our solutions have created new problems. I have no reason to believe that we can "solve" our way out with new technology. Technology is not energy. The easy energy is going. And we humans have a proven track record of using technology to create problems that we then solve with more technology that creates new problems that we then solve with more technology. Thus we have antibiotic resistant superbugs. H1N1 is now resistant to Tamiflu in perhaps the quickest aquisition of resistance by a germ recorded to date, and raising the specter of a fully resistant H5N1 by the time it gets efficient at H2H transmission. We almost created disaster with the Ozone layer and don't know for sure we are OK. We are creating climate change as we use up our oil. We now find that "A powerful greenhouse gas [search] produced largely through the manufacture of flat-screen TVs and solar cells has been found to be four times more prevalent in the atmosphere [ark | more\ark] than previously thought. Nitrogen trifluoride [search] warms the atmosphere 17,000 times more effectively than an equal mass of carbon dioxide. Though not changing climate much yet, we now know there are 5,400 metric tons rather than 1,200 of this anthropogenic super-climate changer in the atmosphere, and with the solar and electronics boom, to be growing at 11% a year."
Corn ethanol has created food problems, use of cellulose to make fuel would create soil problems by not returning organic material to the soils. The high ERoEI of cane ethanol depends on workers cutting as much as 8 to 10 tons of cane a day.
We rush into solutions without knowing the full extent of the repercussions (in some cases it may be impossible to know ahead of time). We applaud solutions without looking at human costs outside our local venue. IMO the solution is not in technological solutions, the solution is in accepting the end of the world as we know it and going backwards as far and as fast as we can and in bringing the population of the world down as fast as we can.

"Part of the problem of calculating EI is that by and large oil energy has created electric energy - whether in building damns, building windmills, building solar panels (including mining, refining, and forging the materials as well as building and maintaining the roads to supply them)."

You are stretching the contribution of oil energy. Most of the energy for dams( steel, cement) or wind turbines( again steel and cement) has come from coal and NG but could come from electricity if no coal or NG was available or if wind and hydro replaces the need to burn coal to generate electricity. In 2009, yes, some oil is used in transport and to move earth and gravel for road building.

"It doesn't matter what the base ERoEI of windmills are if electricity cannot build and maintain roads"

How do you think roads were build in 1908? I can still remember seeing gravel roads being build in early 1950's by steam power steam rollers(burning wood). How were dams built before oil?
Many hydro dams built 100 years ago are still operating, and there is no reason why the dams and electricity grid cannot continue to be maintained when the oil runs out or even when no FF is available. Most oil today is used for private vehicle and air transportation. Very little of our standard of living depends upon being able to drive 12,000 miles/year in a two tonne vehicle getting 25 mpg, or flying around the world. It does depend upon using >4,000kWh per person of electricity. It also depends on not continuing to burn coal to generate electricity.
The most critical large use of oil is for truck and sea transportation, both of which can be converted to CNG but NG availability will be an issue longer-term.

Neil, all the materials involved in making damn, windmills and solar panels are now currently being moved around by gasoline or diesel. Mining iron ore - just what kind of fuel does all that big machinery use? All that earth moving, don't they use diesel. But as oil runs out so will coal and NG as they are asked to do what they already do and fill in for oil. Some think that Coal and NG are at peak already, but certainly if their use increases they will peak soon.

If we severely restricted personal vehicle use then we could extend the age of oil. But that is not happening is it?

Dirt roads. I love them. Used to be maintained by conscripting the local populace to work on them. Of course we can do that again if we just hand out enough shovels and pick axes. But it is the big machinery that makes possible the huge road system we have that supports our fleets of 18 wheelers. Of course we could use rail again, if we hadn't let it deteriorate. I've got it, all those Chinese workers that are now out of jobs because out of work Americans aren't buying stuff can once again be imported to the US to rebuild our rail system.

The old growth hardwoods that were used to power steam engines are mostly gone. Making steam from quick growing pines is not the same as making steam from hardwood,(And of course if we are to use this vs oil I guess we have to cut whatever wood we can find down by saw and ax and then worry about peak trees) Likewise making heat from anthracite coal is not the same as making it from lignite coal. You need more lignite than anthracite which means more mining machines, more dynamite, more rail cars to haul it. Oh yes I do know that humans used to mine it - but that was the good stuff - this stuff isn't worth digging out by hand, it is worth mining only if you blow up mountain tops to get it and use huge machinery to mine it.

My guess is that this bucket wheel excavator uses a pile of diesel in the process of strip mining . I suppose we could put together a bunch of unemployed bankers to do this work and there would be a value in that as it would likely go slower and thus force us to cut back on coal use. Similar bucket wheel excavators are used to mine iron ore.

BTW here is an article on the Hoover Dam in which it says "Carving the diversion tunnels was a slow, tedious process that exposed dam workers to immense danger from blasting, falling rocks and diesel gas fumes spewed by the trucks that carried out blasting debris."
Earlier dams that relied less on oil energy were also smaller and produced less energy. Earlier dams were smaller and produced much less hydro power.

Your guess may be wrong if you are looking at a Bucyrus Electric Shovel: see link

Although tunneling did use internal combustion engines in the 1930's too many became sick with CO poisoning. All underground mining is now usually with electric vehicles.

Australia has a large HV electric grid, nearly all of which is serviced by gravel roads. Many of the service roads in the Snowy Mountains Hydro development built in 1950's were gravel( many still are).

"Earlier dams were smaller and produced much less hydro power."

By 1907, 15% of US electric power was from hydro and 25% by 1920. Many of the dams built in Canada were at the beginning of the 20th Century, still producing 60% of Canada's electricity. True, these dams were smaller than Hoover Dam, which was the largest dam in the world for 80 years. Much of the undeveloped potential in the US(X10 larger than developed potential) is in small hydro where no dams would be needed using run of the river diversion to small(1-30MW)generators. (see reference in earlier reply to Euan).
I am not saying no oil is used in building wind or hydro projects, its just not a critical resource and doesn't account for a large part of the energy used(EI) compared with the large ER its insignificant. Coking coal/NG(for steel and cement) is much more critical but could be replaced with electric arc furnaces.

Hi Neil

You say oil is insignificant in wind projects but the numbers from wind lca (life cycle analysis) don't really back that up. If you look at page 40 of the following;

you will see that FF's comprise 79% of the energy input. 46% of the total energy input comes just from oil. So pretty significant.


You are correct, so is Neil.

Does is not the same thing as must, and lower energy techniques and other energy sources can reduce the fossil fuel input for wind power to zero even though the fossil fuel input to produce them right now is significant.

You also might acknowledge that in the LCA of large wind installations, the embedded energy is also paid back by the turbine in well under a year. Not a bad return on that oil.. and thenceforward, it does not HAVE to be built by diesel equipment, and in fact, you could probably be powering a lot of electrical vehicles, cranes and tools at the WindFarm site with turbine #1 (and the grid), in order to install turbines #2, #3, #4... etc.

Imagine that..

hi jokuhl,

Yes the payback time is <1 year giving eroei >20. And, sure, turbine construction could exclude FF's. But it is still a jump from saying you do not HAVE to use FF's to saying the eroei will be unchanged if you don't. We simply won't know until it has been attempted.

FF's, esp oil, have many characteristics that are not captured by only considering energy quantity. Power density, portability, storability are just 3 of the most obvious ones. How much electrical energy would be required to compensate these qualities and what would that do to eroei? Think about how much embedded infrastructure would be required for rail lines, size of batteries (and all their construction requires) to still struggle to match power requirements in some places. Maintainance and service requirements etc. It's a long list of unknown and interacting issues whose resolution into eroei will be hard to determine until the whole process has been reduced to practice. Until then all we have is assumptions.

And imagination :-)


If we were having this discussion in 1890 you may have said the same thing about kerosene lighting

"FF's, esp oil, have many characteristics that are not captured by only considering energy quantity. Power density, portability, storability are just 3 of the most obvious ones. How much electrical energy would be required to compensate these qualities and what would that do to eroei?"

It's still true that electricity is difficult to store at high density,its not very portable and battery charge is not very stable. Of course what almost everyone( except Edison and Telsa) in 1890 could not see was the electrification of most homes and industry. One reason was the much higher efficiency and thus intensity of electric light, as well as the high EROEI of hydro electricity generation and transport compared with kerosene distillation and transport. It was generally safer( at least at the original 55 volts) than gas light or kerosene lamps.
I would argue that now in 2009, the high efficiency of electric motors and the increased power density of Ni or Li batteries( although still much less than oil) out-weights the lower efficiency of small ICE using oil or CNG. The added bonus is that wind, hydro and solar power are producing electricity so can also avoid the losses of FF conversion to electricity.

Well, if we're talking hydro then I completely agree with you. But there is a world of difference between hydro on the one hand and wind or solar on the other. Hydro is a very concentrated energy form already and it's not surprising that a high eroei can be extracted from it. But wind, and especially solar, are far more disperse energy forms and it may not be possible to get the same eroei from them without FF subsidy.

But you raise an interesting point that I'd not considered before - the substitution of small scale ICE with large scale electricity generation. You may be right that this cancels the fuel quality issues and allows renewables to compete on an equal footing. I shall repair to my databanks.....


For long haul transport, the answer to the question:

How much electrical energy would be required to compensate these qualities and what would that do to eroei?

is, none, electric rail uses substantially less energy than diesel road freight.

Current technology, currently in use, a nationwide grid could be constructed in the US with public finance and funding through user fees, in under a decade. The reason the US doesn't have it has nothing to do with the energy efficiency of the diesel road freight industry and quite a bit to do with the political clout of the oil industry.

Thanks for the link. Valuable data!

Interesting that only 1% of FF is used for transportation. Of the total oil used one third is for gearbox lubrication( newer turbines don't have reduction gears). Coal use would be higher if 90% of steel was not recycled for the calculations.
So looking at oil used per kWh (1.2grams!) To understand how little this is compare that to the fuel used by a gasoline powered vehicle(10L/100km) to travel as far as an electric vehicle using 1Kwh(0.2kWh/km)), we can see that you would need 400g of fuel.
Or the average person in UK uses about 24KWh of electricity a day, so about 27g(1oz) oil if used only wind power. Comparable to the oil used in a fish and chip meal.

However, of that 1.2 grams of oil only 0.012g was used for transport( the difficult part to replace).

Confusing what is done, under current technology and current distribution of internalized and externalized costs, and what could be done, under current technology absent crude oil.

Neil, all the materials involved in making dam[s], windmills and solar panels are now currently being moved around by gasoline or diesel. Mining iron ore - just what kind of fuel does all that big machinery use? All that earth moving, don't they use diesel.

For power harvesting capital with a 10:1+ payout, there's nothing in that list that can't be done by electric rail and NH3 augmented by biodiesel or biogas. Indeed, if rail corridors are used to get around NIMBY objections to transmission lines from the wind farms to the local grid, and to provide bypasses wherever some landowner wishes to hold up a long haul transmission line for ransom, then there are multiple locational advantages to siting the wind farms at attractive sites in the vicinity of rail lines.

The argument presented is similar to the argument often used by traditional marginalist economists, that because in their models, the system tends to settle into an optimum, therefore in the real world, changing what we have now faces the obstacle that things are presently done about as efficiently as possible, and therefore tremendous effort is required to shift course.

So "what is" is not precisely identical to "what must be", but the central tendency to what is, is somewhere smack in the middle of the range of what must be.

Its more likely that "what is" was one of several possible channels along routes of easiest expansion, and that there are substantial efficiencies to be developed through intelligent design which were not, previously, because nobody ever took it as worth their while to design for those efficiencies.

TEOTWAWKI in terms of the end of the age of ultra-cheap Crude Oil is a certainty ... the notion that first wind and river then coal and then oil exhaust the possible bases for industrial economies so that the end of the age of oil certainly implies the end of industrial society is a much stronger claim that requires much stronger support.

The reason that there is some ERoEI "required for industrial society" is the character of industrial society as a wide range of specialized going concerns. If the primary energy source for society has a net ERoEI around 33%, that implies that most of the output of the energy sector has to be consumed by the energy sector, with very little surplus for it to "live off of".

Whether its 12:1 or 10:1 or 8:1 ... it certainly has to be well over 3:1 for the economy to be a substantially industrial economy. If the production of energy becomes the dominant consumer of energy (as in the first agrarian age), then that is going to have to be a subsistence activity, because most people are going to have to be devoting much of their work time to that activity.

I must concur, spend any time on construction site and you see diesel power everywhere all the time. I think it would be instructive if the amount diesel used for dirt work alone where shown, then the percentage of construction dirt work accounted for.

Yes the big drag line shovels at the coal mines are electricly powered. There is a power plant right next to the coal mine burning coal.

On the other end of the scale you have the big oil fields of the North Slope. Diesel pickups running 24/7 every where, parking lot after gravel road after parking lot full of them (it is cold up there and diesel is free on oil company leased property). If diesel isn't powering it from place to place it is generating the electricity that runs it. True when there is no oil oil won't be used to produce it. But unless you have seen such you have little appreciation for how much oil goes into building just about everything.

We are not denying that a lot of diesel is used today on hydro dam and wind turbine sites. These structures also produce a very large amount of energy for a very long time, long after the diesel trucks and graders are long gone. The study quoted above for wind turbines in Denmark showed that only 1% of energy used for manufacturing was for transport, 0.01 grams oil per kWh.
The issue is whether we can replace most FF and especially diesel with renewable fuels. Since these structures are producing electricity, lets see what can be manufactured by electricity instead of oil or other FF. Large energy inputs are for steel and cement but at least the steel can be recycled( assumptions in Danish study) and these can be produced by electric furnaces. We may still need to use diesel but if its a teaspoon(1gram)/person/day to supply all electricity that's a very much reduced problem compared with the present consumption of 1-2 gallons of gasoline(>2000grams)/person/day in US and Europe.

We still may need oil for gears( 0.4grams/kWh) still a very small amount, and may have to use bio-lubricants for this purpose rather than burning as bio-diesel or even better than using for cooking fish and chips.

Now if you are referring to diesel used in oil drilling in remote locations we know that must be very large because the EROEI is much lower for oil now(10:1) than wind or hydro(40-200:1) energy. I can't see a lot of this oil drilling energy being easily replaced by wood or even electricity unless oil becomes really really valuable, where portable nuclear plants or wind turbines etc may be cost effective. We will stop burning oil in motor vehicles, trains and ships long before we reach that point.

No arguement there. Just kind of saying you have to walk away from the computer screen once in a while and immerse yourself in the real world of oil to get a true gut feeling of what we are talking about. I was merely trying to generate a real mind's eye picture of what is, little more. Not everyone has a chance to get out into the field. My picture was actually a little out of date as natural gas turbines provide most electricity up there anymore.

Euan, good continuing refinement of the EROEI bottleneck dilemma. Noticing there were no references to solar, I'm providing one for solar PV (including balance of system):
- 8-20:1 US DoE National Renewable Energy Labs

Something doesn't jive here - boundaries or something. I called several solar companies and got quotes for my house - on DOLLAR payback at current rates of electricity (which I understand is NOT an EROI analysis, but should give us a clue, like it did with ethanol), it is a 40 year pay back - 500kwH system is $58,000 (without delivery or installation) for my latitude - my monthly electricity bill is $120 per month average ($30 some months) so this is the 'correct' system for my needs.

1)Do they test the EROI of solar on a house facing south in the Arizona desert?
2)If the EROI is accurate, where is the disconnect in actual dollar pricing? Are they leaving out some large non-energy input?
3)IF answers to 1) and 2) are 'no', then solar will NEVER scale except for distributed generation - because very few will be able to afford it. Economically, for me, it doesn't remotely make sense. Unless I am being had by the solar quotes - but I get similar quotes from everywhere. I think it gets down to sunk costs - the energy and materials in our current electrical grid were all put in place with very cheap natural gas and oil - for INDIVIDUALS to bump up the % of discretionary income to switch to solar en masse can't happen/won't happen at these prices.

What am I missing? (surely something...;-) Thanks in advance.

Isn't the answer to #2 R&D? Computer chips are expensive too, and they cost little to produce, and do not harvest any energy at all.

500kwH system is $58,000 (without delivery or installation)

That seems a bit high unless you have really bad insolation, was it a grid-tie?

no -half the cost (almost) was batteries. I live near Minneapolis MN - it was assumed 4.6 avg hours of sun per day and worst month (Dec) with 2.4. We should probably do a post on this - perhaps Will Stewart or someone with expertise can help me. I am discouraged because I had a built in perception that solar was cheap and getting cheaper.

Let's schedule that interview...

half the cost (almost) was batteries.

To be fair, counting the cost of batteries is apples and oranges, since a utility is not going to be providing you backup power when their grid goes down. There is a cost associated with added capabilities of being up and running when your neighbors are out of power due to ice storms, terrorist activites, branches hitting powerlines, etc. If you were straight grid-tie net-metered with no batteries, then the system cost would be dramatically different.

The batteries in my system, for example, are strictly for grid outage periods. Many people have generators, though during extended outages, I hear them slowly shut off one-by-one as they run out of stored gasoline.

I'll not detract this post further on this specific example - yes lets get than interview queued up. But regarding batteries, it's my opinion that their cost must be included, insofar as our societal energy use (via electricity) is 24/7 on demand availability. If grid were not around and I had to replicate this 'energy quality' I would need the amount of batteries recommended, or change my energy. By the way, what would be Liebigs Limiter to get hundreds of millions of tons of lead acid batteries around the country if this were to scale? (I'll save it for the interview).

I think otherwise, Nate. Solar - to be effective - requires a different paradigm. Not the 24x7. The problem isn't the solar, it's the 24x7 paradigm - a fossil paradigm. I've got a fleece cap on right now. My girl and I would really like a real bear rug to lie on in front of the wood stove. There are some tough, dark days in January. But days are noticeably longer now in Feb and I've shed part of the long underwear already. And despite the cap, I don't have a fire going. I think that's pretty good. And I know how to make it better, but I'm lazy.

Suppose, for example, a system in Maine with only enough battery capacity to carry LED lights for a couple of days. And those could be charged on the pedicharger if need be. In the depths of winter, no need to worry about the frig or freezer if you have a cold box. No need to worry if your selection of food is Maine winter appropriate - a frig is next to irrelevant. Run the overcurrent to some sort of NPK - something that uses the power *directly* - and that does not store it as does a battery. Well, maybe your plug in car and laptop. Summer outages would be different, but since I'm in Maine, I don't think much about them. There are veggies and I like a good home brew at cellar temperature.

Right now, I'm running a 60watt light in my chicken coop 24x7. My hot water tank and cooking are propane. My business - also at the same address - ISP runs several 24x7 computers. Move them to the in-town colo where most of my other gear is already. Next year I go off grid, though maybe not off propane. The chicken coop I can fix too - this year I had to move it to eliminate plowing and shovelling. Half-farmer can implement an energy independance plan in five years.

John Howe has a system built around a golf cart. But why not build a system around the car battery? Park it in a garage so it's warmer, dry and accessible. Double up the battery. Quadruple the battery. Considering the car, the weight is not an issue. Plug it in and tie to the house to those LEDs. A bit of an issue reconnecting after the car has been away for a few days, perhaps. I think my soils test results I just got back today are a bigger issue than my electric bill. On two acres.

Cooking and hot water is a "point of flame" issue - not something appropriate for solar PV. In my dreams excess from the solar PV would go to some variant on the Haber-Bosch process. [Sorry - chemistry is NOT my thing, but if strandedwind can do it so can strandedsolar.] Minimize the storage. Cooking and hot water is solar thermal, burn wood or eat raw.

Liebig's Limiter on all those lead acid batteries? Skip the batteries.

Linear programming - the solution always at some extreme. Real world engineering tempers that.

cfm in Gray, ME

I think otherwise, Nate. Solar - to be effective - requires a different paradigm. Not the 24x7. The problem isn't the solar, it's the 24x7 paradigm

This is well said. I was trying to reconcile EROI with current system, but we could get by with much lower EROI systems if we have behavior change.


Now the numbers seem a lot better. When you are thinking about it, make sure you keep the size of your battery bank under control, since if you lose power you can lower your consumption until power comes back. Keep in mind Minnesota's net metering looks pretty liberal so you can use the grid as your battery cost wise.

All of the solar calculations are without batteries, assuming that the grid will still provide you with most of what you need. If the grid is your concern, you really need batteries. Batteries don't last all that long, so if you want to look at the real long term cost, you need to factor in several sets of replacement batteries (assuming you can still buy them).

If your concern is long-term availability of electricity from the grid, I am not sure "payback period" is the relevant measure. The price of electricity from the grid becomes infinite, so any other cost becomes better (but not necessarily affordable.)

If your concern is long-term availability of electricity from the grid, I am not sure "payback period" is the relevant measure. The price of electricity from the grid becomes infinite, so any other cost becomes better (but not necessarily affordable.)

Change the metrics, change the paradigm. It's not like there is much choice when costs go infinite. Maybe at that point you get so pissed off it's a matter of ego and "you will beat the system" and that's all it takes for you to go a day without a shower. Or two or three or a week. infinite costs means something "doesn't work". Next.

I suspect Airdale is doing just fine right now in KY. I don't see how that resilience extends to city folk.

cfm in Gray, ME

If the EROI is accurate, where is the disconnect in actual dollar pricing?

Capital material and processing costs are higher per kWh (the process for refining them to the end product is complex and expensive). Note that panels are not a fuel, but energy conversion devices harnessing an energy source that has no direct costs, so a direct comparison this way is problematic.

solar will NEVER scale except for distributed generation

That depends upon:

- How external costs are treated in the future
- The advances in marketization and production of much less expensive PV technology

You should be able to get a solar electric system from a reputable integrator for no more than $9 per watt. Make sure they have at least one NABCEP certified individual on staff.

It looks like MN has a $2,250 per kW rebate. Tie that in with the new 30% ITC and the sale of the system's RECs, (with an assumed 7% inflation rate on the price of electricity) and your "pay-back" should be 6-10 years.

Remember that having a solar electric system is worth a lot of $$$ and piece of mind and should never be thought of in terms of pay-back time.

thank you - but here is the problem. Those rebates might help ME as an individual, but someone is paying those costs - so from an aggregate EROI perspective, the way Euan has shown in the graph, individual PV just doesn't make energy sense with respect to what it is replacing unless someone lives where the sun shines (alot). There are obviously qualitative reasons to do it (peace of mind, backup, etc.) but those shouldn't factor into an energy analysis.

I am going to try and do a back of envelope on the rural/suburban population and their kwH use and see what it would require in terms of batteries, panels and dollars to replace this usage - just to get a sense of what it would be. My gut says its a non-starter and that solars future is in hot water (which I have, solar cooking, and Sterling type central PV plants that distribute the energy via transmission - just as in wind, solars cost decreases with size (for different reasons).

But thanks for your links - again for ME, it makes it more attractive, but just like for ethanol, someone is paying the subsidy.

EROEI from Euan's definition above is strictly the ratio of the amount of usable energy divided by the energy needed to extract/capture that usable energy. Price doesn't enter into the equation at all. To use a metaphor, it's like saying the amount of energy to propel a car is directly related to the price. While in some instances it would work, it would fall flat on its face with many other comparisons, including the Prius, the Volt (when it comes out), most Porsches, Rolls Royce, the Tesla, etc.

Price can be useful in other comparisons, but not one based strictly on EROEI.

The solar PV EROEI reference I provided above is based on 1700kWh/m2 per year, which is 4.65 kWh/m2 per day. Looking at the map, you can estimate where those conditions are realized;

Nate, it's even worse than you suspect. I got 2 quotes for solar powered heating (supposedly more cost effective than PV) and the economics were awful - I would earn more interest in the bank (even now!) than savings on gas for hot water. And that was with a govmnt subsidy.

When I mentioned the possibility of PV instead the guy just laughed. Mind you, I do live in Scotland.....


My understanding is that part of the problem is just looking at the panel costs where they are manufactured. By the time you actually get them installed on a given home, the cost is a lot higher.

We may be conflating two different things in looking at costs to homeowners, but that is what real people look at (unless they have massive government subsidies).

This is why Solar is not happening ....

folks are not willing to conserve to the point where they can afford Solar.

It's not happening because there's no incentive to do it. The vast majority of people don't think the grid is going to either go away or even become noticeably less reliable. Why would they? TPTB tell them all is well. Their whole life experience says the grid will be fine. Probably 30% of more of them don't even understand where electricity comes from.

Faced with that, why would anyone even spend 2 seconds thinking about spending tens of thousands of dollars on solar?

I called several solar companies and got quotes for my house - on DOLLAR payback at current rates of electricity (which I understand is NOT an EROI analysis, but should give us a clue, like it did with ethanol)

You should have stopped there.

The US $ is not a Joule-based currency.

Certainly the EROI of a solar installation is going to vary with the amount of sun you have. Solar will certainly be a better investment in Arizona than it will be in Minnesota. It will be a long time (if ever) before solar is going to make sense in Minnesota. That does not mean that a similar installation would not be closer to paying out in Arizona.

The other issue is storage. If you require storage it is going to drive down the EROI. Since the demand is peaked in the daytime it seems that the grid is a better storage mechanism than batteries, at least until the penetration is far higher than it is currently.

"It will be a long time (if ever) before solar is going to make sense in Minnesota."

Welllll, that depends. If net metering actually paid back according to the actual cost the utility was paying for electricity at the time, PV even in MN would pay for itself fairly quickly.

That's because in the middle of the summer when temperatures are hot, MN gets as much insolation as parts of Florida. And those are exactly the times when electricity demand is the highest because of AC demands. That is also when utilities have to buy a lot of electricity from Canada and other places, and they pay a lot for it.

They are willing to pay a lot, because the alternative (traditionally) would be to built a whole new power plant that would just kick in on the hottest days of the summer to cover those peaks, and that is clearly not economical.

But having a whole lot of PV around would help shave off that peak demand. So it can be argued that it makes sense, even in MN.

Again, as important as EROEI is, the specifics of timing and interconnection with others systems can be just as if not more important in any given circumstance.

Written by Nate Hagens:
...500kwH system is $58,000....
...half the cost (almost) was batteries. I live near Minneapolis MN - it was assumed 4.6 avg hours of sun per day and worst month (Dec) with 2.4.

Assuming "500kwH" means 500 kW·hr / year guaranteed minimum power = 1.37 kW·hr / day, your numbers seem too large. During a cloudy day, a PV panel outputs about 20% to 25% of its sunny day power. Do not think of winter as having 2.4 hours of sunlight and 21.6 hours of darkness during which the batteries must provide all of the power. Most buildings use less power during the night than during the day. If the PV panels output 1.37 kW·hr / (cloudy day), the batteries will be recharged the next day and always stay near full charge. If the daily cycling is between 95% and 100%, deep cycle lead acid batteries will last about 14 years. Do not go overboard with the number of batteries.

For example, I have too few batteries in my PV system to properly match to the charging current from the PV panels. The literature recommends 100 A·hr of battery capacity per 1 A of maximum output current from the PV panels. I have 8, 6 V ~400 A·hr batteries (aka forklift batteries) being charged by ~27 A peak PV current at 12 volts. That works out to be ~59 A·hr / A. I compensate for the imbalance by using a relay switched regulator to control 20 A while the remaining 7 A is connected through a diode without a regulator. The batteries get charged with 27 A when discharged and 7 A when close to full charge. My previous battery array lasted 14 years. You could hook up the output of two independant relay switched regulators in parallel to achieve something similar.

Crystalline PV panels are more efficient in cold weather. You can place a horizontal reflector in front of the panels to concentrate sunlight in the winter without overheating them. Snow on the ground reflects sunlight making it brighter than an assumption of direct illumination. Snow and rain clean the air making Sun brighter during the winter. There is less air pollution during the winter making Sun brighter than in Summer.

If half of your daily power is provided by the batteries during winter, to keep your daily cycling within 95% of full charge you need:

1.37 kW·hr * .5 / (1 - .95) = 13.7 kW·hr of battery storage. You only need six, 6 V, 400 A·hr deep cycle lead acid batteries to stay within this range. I suggest you have at least 8 of these batteries to power a 1,200 W microwave oven. If a refrigerator and 1,200 W microwave oven could operate simultaneously, then you need a few more.

I notice the price of the batteries has nearly doubled over the last few years to $280 / battery up from about $180 / battery. Peak oil may drive the price up.

Insolation for Duluth, MN

Thanks Will - got it. 1 to 4 years energy pay back on a PV system with 30 year life cycle seems to suggest eroei in range 8 to 30? This of course for a sunny climate - or does the range reflect the range in sunshine?

I'll try and add this to my chart + a figure for nuclear of 5 that Nate provided yesterday - which seems low to me.

Definitively a great chart, I think maybe 2 other dimensions are missing but I don't know how it could be represented: 1) flow rates; 2) energy quality (i.e. primary energy). For instance oil has to be burn to give useful energy whereas wind already produces electricity. Low flow rate energy sources are also a problem for an expanding economy.

Weighting by size of source (flow rate), type of output, and for time series would all be interesting for someone with great charting and math skills to do - beyond me I'm afraid.

Problem is getting hold of reliable data.

The EROEI mantra is uncritically accepted here as a metric of something related to the survivability of human civilization.
First it was claimed to have been derived from the laws of thermodynamics(without proof), then from ecological economics(without proof).

It doesn't even make ordinary common sense.

Suppose you double the efficiency of energy using appliances---obviously you could use lower EROEI energy.

It considers all energy to be equal, as if electricity was as useful as stored energy like oil.
Continually generating electricity from fossil fuels is the least efficient use of depleting resources.
It ignores economies of scale such as the advantage supergiant oilfields over tiny isolated pockets.
It doesn't reflect the real rate of energy production and falls back on lame excuses such as 'subsidies'.

EROEI is a flawed, empty metric--perfect for closed minds.

Make everything as simple as possible, but not simpler.
Albert Einstein

First it was claimed to have been derived from the laws of thermodynamics(without proof), then from ecological economics(without proof)

EROEI is a flawed, empty metric--perfect for closed minds.

All false. EROI is translated to the human sphere via anthropology -it's foundation is optimal foraging theory which is a sub-discipline of biology/ecology not economics nor thermodynamics. Those creatures that had a surplus of energy output vs the energy they put in had adaptive advantages, including all of your ancestors. EROI just extrapolates this into an exosomatic framework. You're the one with the closed mind.

Thanks, Nate.
I haven't seen this before.
The graph is interesting--it has rank(EROEI?)versus energy per unit time(power, not energy)plotted with an 'optimal'rank and even a possible decline
in 'power'above the optimal(this resembles 'economies/diseconomies of scale' an inverse parabola, not asymtope).

Basically it is a peak demand hypothesis.
I would guess you are saying that people will
stop looking for energy as EROEI falls(as energy becomes more expensive people won't want it--a rather conventional economic analysis).
People were still buying $150 oil when the speculators cashed in.
Tar sands and ethanol operations continue to operate and even in some cases expand despite horrendous EROEIs and terrible markets.
Still, it is an interesting approach worth further thought.


Where do you get your information?

...ethanol operations continue to operate and even in some cases expand despite horrendous EROEIs and terrible markets

Ethanol operations are dropping like flies. 14 of 16 plants run by Verasun have shut down.

Read this to learn about the how ERoEI applies to biology, human history, and current society.

Please thank Dr. Hall for making this paper public access.

EROI guy,
You are confusing the financial problems of
Verasun and production. Production in October was at an all time high(675000 bpd~22 mbpm) as was shown on the last page of your referenced report.

I read the article.
To be honest it's goofy.

You have 3.6E18 joules for the energy required to make ethanol. This is more 33% more energy than is in 36 billion gallons of ethanol(2.9E18 joules).

All studies except Pimentel/Patzek show that corn ethanol is net energy positive.

It is true that we use a lot of energy to make ethanol, but if we burnt corn stalks as a true energy crop for distillation(instead of feeding it as sillage to cows) we would reduce fossil fuel inputs tremendously.
The energy of distillation is 50000 Btu/gal(70% of ff inputs)
A typical acre has 4 tons of sillage(baggase) and produces 150 bushels/390 gallons per acre--that's 20 pounds of bagasse per gallon of ethanol. Bagasse gets about 4000 Btus per pound so that is 80000 Btus per gallon much more than the 50000 used for distillation.
Based on a 70% reduction in fossil fuels due to burning bagasse, the 3E18J becomes ~1E18.

Your number for transport to customers .24 XJ, 6319 Btu/gal.
is much higher than the number of Shapouri(USDA 2001) 1487 Btu/gal.

Apparently, you have decided that to use ethanol a whole new energy distribution system is required; i.e. 2.9 ethanol x 10.9/16.5=1.9.

But that's not the idea of 'gasohol'.

The idea is to mix ethanol in with gasoline; 36 billion gallons would be equalize to 156 billion gallons of E 25 which would could power cars(all Brazilian cars can do at least E24).

A U of Minn. study suggests that most existing cars can handle E20(close to E25).

There is no need for ethanol, pipelines. Corn/sillage could be transported in 100 ton rail cars like coal and taken by tanker truck from a local refinery to gas station where it could be mixed into the gas station storage tanks. There simply is no need for a vast infrastructure.

If I add up your entries for ethanol,

1)3.6XJ -->1XJ if sillage is burnt for distillation if we treat ethanol as a true energy crop (or becomes 3XJ if we don't use bagasse.)

2).24XJ becomes .06---(.24 x 1487/6319)
3)1.9XJ becomes maybe .7?

Total cost--1.76
Total energy out 2.9 XJ 36 billion gallons of ethanol.

The article says that any fuel with an EROEI of less than 3 will end up being subsidized by the petroleum economy.

This simply doesn't jive with the fact that current corn ethanol production reduces the dependence on petroleum by using cheaper natural gas and coal to make ethanol.

From USDA Shapouri(2001)
22% of farm input FF(4117 Btu/gal) is for petroleum derived gasoline and diesel plus
2210 Btu/gal for corn transport and 1487 for ethanol distribution(transport)=7769 BTU/gal
about 10% of all fossil inputs.
So 10% of the input energy comes from oil
(.066 gallons of oil) goes in and .66 gallons of oil (1 gallon of ethanol comes out)comes out! That an ORoOI--Oil Returned on Oil Invested of 10!

This pretty much disproves the idea that petroleum supports/subsidizes ethanol.


Nate -

I have been loosely following (and occasionally participating in) this EROEI debate for quite some time. It appears to me that we are no closer to reaching a consensus as to what it all means than we were over a year ago. I am somewhat of an agnostic on the subject of EROEI, and think neither that its a flawed concept nor something that gives anything close to a complete picture. It is highly useful, but has its limitations.

As I see it, where people often get on shaky ground when using EROEI is when they try to extend its applicability from straightforward technical applications such as comparing the net energy made available by say wind power versus ethanol-from-corn to more nebulous things having to do with human behavior and the viability of societies in general.

While those are both worthwhile areas of study, I sometimes question whether the concept of EROEI is as helpful in these studying these areas as you appear to think. Everything that makes a society succeed or fail cannot be automatically be blamed on either poor EROEI or poor capital management. Never underestimate the power of human perversity as a driving force in screwing things up.

In my view, the most valuable thing that EROEI tells me is how much of a capital investment burden will be required to obtain a given amount of net energy. To illustrate my thinking in this regard, consider a fictional situation in which there was an unlimited supply of energy that we could tap into, say moonbeams, for instance. But let us also suppose that obtaining this moonbeam source of energy involved an EROEI of only 1.001, which is to say roughly that for every 1,000 units of energy put in, you get 1,001 units of energy out. Even though the energy source is unlimited and 'free' for the taking, one would need to go through an extraordinary effort to tap into it, and that effort directly translates into capital investment. So, given such a poor EROEI, it would very likely be physically impossible to build the absurdly large facilities needed to realize the net energy from those moonbeams.

In many respects this not much more complex than realizing that a person might prefer to walk 2 miles for one hamburger rather than 6 miles for 2 hamburgers. The expenditure of 'energy' is not just physical caloric energy, but also what one might call mental or emotional energy. Or just plain time and effort. One can argue whether that person should be eating hamburgers in the first place, or whether he should be seeking more healthy food grown locally, but within the confines of that narrow comparison, EROEI does make some sense.

So, with regard to using EROEI, render onto Caesar .......


It is highly useful, but has its limitations.

I totally agree and have been saying this since my first essay on TOD, about a fictional society who faced lower energy gain than it had previously been used to. (The result was an increase in non-energy limiting inputs and a decrease in consumption). EROI is a blunt instrument, not a laser like tool. I have a paper pending "The Limitations of Net Energy Analysis for Energy Policy", outlining the reasons why. But I suggest rereading that sasquatch post, or at least the 'bottom line' from 2006.

But energy gain is what allows us to do work. Less energy means changes in other areas, particularly non-energy inputs. I think what HAS been accomplished in the last couple years in discussing this (at least from my perspective) is the concept of a portfolio approach with natural resources as limiting inputs (not $). My papers "Energy Return on Investment: Towards a Consistent Framework" and "A Framework for Energy Alternatives: Net Energy, Liebig’s Law and Multi-criteria Analysis" try and take a stab at formulating such a framework.

Euans chart above attempts to graph the aggregate energy gain, which is EROI x Scale on various sources. With that we have to build out renewable energy infrastructure with the highest return, unless such a return is hampered by other non-energy inputs such as water, land, soil, environmental damage, etc. If so, then these limiters will favor a lower EROI tech. If the technology has no non-energy limiters, we are back to maximizing EROI, for that gives us the largest energy cushion for maintenance, redundancy, repair, emergencies, etc. If ALL energy alternatives have increased externalities or lower EROI, we are going to have to reduce consumption (aka no more global growth). You can look at it in terms of capital, or energy - but we need energy to deploy capital. In the end it will come down to how much sub $200 oil flow rate we have and the externalities that accompany it.

Net energy gain has been proven in nature to be a very big deal. In human societies it is more complex because of the issue of quality. EROI is just a biophysical tool - no one (especially me) is saying EROI is the answer to our problems. My bottom line reply to your query is that I now see the bigger picture better than I did a few years ago -we need to maximize our portfolio return on our limiting inputs - very soon, natural gas and high API crude oil likely being 2 of them, with water a close third. Hope that makes sense - if not please ask. I am well aware of the human proclivity for blindspots and am open to being told my own.

It is really productivity gain which matters rather than energy gain per se. We expend labor and other resources extracting energy and thus lose potential productivity, but we more than gain this 'lost productivity' back elsewhere in the economy by utilizing the net energy obtained. It is quite easy to construct thought experiments in which a low energy gain process has a very high productivity gain and also the converse example where a high energy gain process has a low productivity gain. Although these thought experiments are not 'realistic', they make evident the interplay of multiple resources in producing economic value even in a zero'th order analysis.

The articles aren't free, Nate. Free them up. That's one of the things that going to have to change in a lower EROEI environment. Information has to be free. Only by standing on your shoulders can others see ahead. Ben Franklin would agree. Swadeshi.

Hi majorian,

At last someone besides me sees the truth. Thank you for having the guts to tell it like it is.

There are not many of us here. Logic has been abandoned in favor of numbers without meaning.

Don't let the attacks discourage you. You are right on.

Yup. He's right on that energy gain has no biological underpinning in the evolution of life. Don't worry X - 99.99% of society agrees with you in using numbers that only have short term meaning ($$). The ones that look ahead to biophysical principles are a tiny minority.

(I wouldn't even reply to you other than your NON-corn-ethanol comments are cogent and well-reasoned).

I hypothesize that in the future, if TOD is still live, and you are still reading, you will be an advocate of whatever government decides is the best use of your land, and gives you the most profit, as measured by society at that time. Corn ethanol will be a thing of the past, as will your fervent support of it.
Party on.

How would we determine the EROEI of waste gas?

Gas from waste could heat almost half the homes in the UK, according to a new report from National Grid.

It says obtaining more gas from waste will help cut carbon emissions, improve energy security and compensate for the shortage of landfill sites.

Renewable gas from landfill sites and sewage works provide 1% of the UK's gas at present.

Today's report says an extra £10 billion investment could increase that to between 5 and 18%.

The article seems to refer to both microbial methane and from waste gasification. Maybe the first type could be increased from 1% to say 10% of current gas use. The second type is struggling to get past the prototype stage. Syngas needs to be cleaned of tar before catalytic conversion to methane and doesn't have the stoichiometric hydrogen carbon ratio. It sounds like they want to lower the energy density of piped gas, currently around 40 MJ per cubic metre I believe.

In future it may be possible to blend natgas, biogas and syngas which will preserve the sunk cost of the gas grid and still enable CHP and depot fuelling of CNG vehicles.

Weren't most of the gas networks in Britain filled with "town gas" (water gas or carbureted water gas from coked coal) before they were switched to natural gas?

Town gas is far more dangerous (it's got a large proportion of carbon monoxide), but gas works aren't exactly high-tech.  If coal mining was restarted, Britain could have a very clean-burning fuel delivered to homes and businesses even if natural gas imports disappear.

Because we cycle in new members, I think it is important to make clear that EROEI is measured at the well head (for oil or natural gas) and at the mine mouth for coal, at the wind turbine for wind generated electricity. Energy is not used at the well head and a lot of other factors must be added before we can estimate what is the minimum EROEI for industrial civilization.

Here is a natural gas example to help give an intuitive feel. The well head price is the lowest. This price would include all energy inputs needed to drill and operate the wells. Also listed are the commercial and residential prices. Notice these prices are more than double the well head price.


It takes a huge amount of energy to compress natural gas into pipelines, ship it over long distances, pump it into caverns to store for winter usage, and distribute it to customers. The energy usage of all the staff, all the steel in the pipe lines, all the meters and meter readers, etc, must be paid.

If natural gas were at less than 2:1 EROEI you can quickly see how there would not be enough energy profit to pay for the drilling and the distribution, despite that 2:1 is a larger number than 1:1.

But we have even more costs that are not factored in, such as the cost of the furnace that burns the natural gas or the cost of the industrial equipment that uses the natural gas for fuel.

So the minimum EROEI for domestic US natural gas usage is likely above 3:1 absolute minimum. (below that there is no natural gas industry at all). And is likely the much higher 5-9 value that Euan is stating.

Notice these prices are more than double the well head price.

Call me less than impressed: it is not difficult to find items where the input raw materials are pennies in cost, but the final retail price is 100x larger.

As they say, "what the market will bear."

I also have to wonder about the "huge amount of energy to compress natural gas into pipelines, [...]". Good heavens, there are thousands of miles of gas pipeline in North America. If it is so horribly inefficient, how did the billions of dollars spent to build it all ever come to be? Supporting this are a few google searches which indicate that the losses for piping the stuff amount to ~0.5% of the energy content of the gas per 100 miles of pipeline.

The positioning of tar sands seemed ok to me on this graph - that is until the Opti/Nexen JV at Long Lake started up.

Its EROEI is well to the left on the graph and - I submit - entirely sustainable.

Only 20% of tar sands are mined so this sort of development for in situ projects is one of significance. Human ingenuity has yet the potential to dispel the worst case scenarios for post peak. While I am one who believes the supply peak may have happened already, the delays attendant to the credit depression may yet allow some very efficient alternatives to be put into play :-)

The water implications for scaling tarsands in situ as opposed to mining are complicated - but the bottom line is there is no free lunch and while burning the bitumen in situ increases the energy return (because it reduces the energy input because that bitumen basically has no alternative use), water impacts will still limit the type of numbers projected by Canadian authorities. Pembina Institute has a very detailed analysis on water consumption and water withdrawal impacts on Athabasca River for mining and Alberta groundwater resources in case of in situ, in this pdf.

The Pembina paper that you cite is out of date (2006).

I have already posted several times that water is not and will not be a problem in oilsands production.

You wouldn't be employed in tar sands related industry would you?

I know folks at Pembina that worked on that report - while the publication might be outdated, the water impacts are not - please post references on the improved water usage technology on in-situ production. Sorry if I missed previous links.

Hi Nate,

I have invested in a number of in situ projects where they CLAIM to recycle 90% of the water, also a couple where they do have a good recycle rate.

The Long Lake project uses non potable ground water, then recycles it and by using the 15% of the bitumen that comprises asphaltenes to generate steam, electricity and hydrogen, they are able to change their EROEI from marginal to competitive - and do the same for operating costs. The energy recycled does wonders for reducing their natural gas requirements :-)

Their capital cost for project set up is correspondingly higher. Like all pioneers, Opti have had commissioning issues that they have just about surmounted - but they are now selling a high grade crude from their process. So let's educate the knockers eh?

The net energy aspect of conservation materials and methods ought to be considered when establishing public policy. For instance the amount of energy needed to manufacture fiberglass insulation is several times that of blown-in cellulose which is mostly recycled paper. Also each extra layer of insulation offsets less energy use than the one before it. Therefore it is better to insulate two houses to an r-11 level than one house to r-22. The same question needs to be asked about auto technologies. Would it be better to apply hybrid tech to 18-wheelers before doing it with small cars? Going from 5 mpg to 10 mpg saves 5 gallons per 100 miles while going from 25 mpg to 50 mpg saves only 2 gallons per 100 miles. Cool Roofs and Cool Pavement carries a big bang for the buck but if white concrete takes more energy to produce than the energy use offset from a lower urban heat island effect needs a close look.

Would it be better to apply hybrid tech to 18-wheelers before doing it with small cars?

You see a lot of trucks in stop-and-go traffic? But even if you did, given that the fuel consumed by transport trucks is a small fraction of that consumed by passenger cars, the answer would remain "no".

I have seen a lot of large trucks stuck in traffic jams on freeways as well as using city streets. I read a study some time age done in Australia which showed the average 18-wheeler shifted gears an average of once per kilometer. This argument was used for the use of an hydraulic hybrid drive system. While big trucks may have better ton/mile energy use than a small car they are on the road much more per day as much as 10 hours per day per driver. The average small car puts on less than 40 miles per day which makes the inclusion of an engine unnecessary. Even using old style Pb-acid batteries electric cars make more sense than a hybrid.

"Would it be better to apply hybrid tech to 18-wheelers before doing it with small cars? Going from 5 mpg to 10 mpg saves 5 gallons per 100 miles"

For the amount of mass moved per BTU trucks are far more fuel efficient than hybrid Prius. Average truck may use 0.20 gallon per mile but weigh 75,000lbs (37.5 tons), so they produce 188 ton miles to the gallon. Prius uses 0.02 gallon per mile but weighs 2.3 tons (with two passengers)so it produces 115 ton miles to the gallon. Trucks could get slightly better fuel economy in city driving by going to a hybrid drive system, but I doubt they could get much improvement in highway driving. Weight of battery storage would also reduce the carrying capacity of a truck, now around 22 tons for US trucks, with gross vehicle weight of 40 tons.

Trains offer much more opportunity for energy savings using hybrid technology and GE Transportation was working on a hybrid locomotive. I think the project got shelved since diesel fuel prices declined so much last year.

The standard locomotive in service last time I looked was a diesel-electric. That is a diesel engine with an electric drivetrain. The ONLY thing necessary to make such a beastie a hybrid is a "battery car" with a good secure electric hookup mechanism.

It would probably add about a quarter ton to the locomotive for the service bus and guards if my recollection of the energies involved is anywhere near accurate and external power capability is not already built into the design.

The technology to allow semi tractors to run diesel-electric may have advanced enough that it would be more efficient than a mechanical drivetrain now. It would certainly be easier to operate and allow more flexibility in design changes down the road.

I like the idea of upgrading existing trains to make use of battery electric capacity, it also opens the option for electricfying just the sections of track when the train is accelerating / braking and travelling uphill. The rest of the time the train can cruise on the on board diesel engine. Obviously this is not a long term solution, but could be a transitional wedge. In an ideal world the train could also charge electric bikes or cars on board, as part of a truly integrated transport system.

I didn't see photovoltaic and nuclear on this chart. I saw numbers long ago on nuclear, and I believe EROI was something like 4.8. Most of the energy going into nuclear is indirect, that is, construction of the plant. That is an old number, and is probably low because these plants are generating more power with increased uptime and incremental process improvements.

Also, it would be interesting to see the EROI of fossil fuels expressed as converted to electricity, computed from the typical overall conversion efficiencies (combustion to steam to turbine to generator to electricity) of the respective uses of each fuel. In the case of transportation uses we would use gasoline and diesel engine efficiencies, assuming the output was used to generate electricity.

I talked to General Electric about their natural gas combined cycle turbine process and they told me it was 60% efficient. I have no idea what percentage of natural gas generation is combined cycle, but I know a lot of capacity was installed in the last decade.
I’m not sure what the overall coal fired electric conversion is, but I believe Smil said something in the low 30%. (My Smil book is misplaced or lost).

Today’s diesel engines are very efficient and perhaps someone knows the efficiency. I don’t have current numbers on gasoline engines either.

Electricity is the ultimate energy carrier. It can be converted to work with 95% efficiency in industrial motors. Small household motors are terribly inefficient, something like 45-55%, but my college roommate, an electrical engineer, who worked 30 years for a motor manufacturer, says that it’s a cut throat business and they use the cheapest designs and components, such as the magnetic steel. I asked him if the efficiency had improved over the years and he said “no”. However, the Energy Star appliances (mostly confined to refrigerators and air conditioners) and premium efficiency motors are different designs, some having high tech permanent magnets using rare earth metals.

Another thing to consider for electric cars is battery cycle efficiency. Lead-acid has the highest. We could easily have low cost, ultra light vehicles (not golf carts) for around the neighborhood and to the grocery store trips. All cars don’t need extended driving ranges and 3000 pound weights.

As for oil sands, I believe the bitumen supplies the fuel for the conversion process, so the EROI should be based on external energy supplied to the process (diesel or electricity for mining equipment, natural gas for upgrading).

I saw numbers long ago on nuclear, and I believe EROI was something like 4.8.

~50:1 is a more reasonable guess, and, carefully note, one based on an extremely inefficient use of fuel.

Mdf's link ( has very good information in table form comparing input and output for various energy sources.

The input/output for nuclear, 1.35%, gives is a very high EROI compared to PV, coal, natural gas and wind.

France was right to go nuclear. For us to make the transition away from fossil energy, we will need to spend the minimum amount of energy and resources possible. Nuclear would be a better use of stimulus money than what is proposed.

All we lack is political will.

There is a lot of crazy data on Nukes out there. When Robert Powers wrote his Oil Drum Piece on Nuke EROEI, I posted this addendum based on 11 prior studies. EROEI somewhere from 6 to 12 depending on costs of decommission.

Coal generated electricity is about 9 EROEI which is 11% of output energy needed for input. If Nuke was 1.35% then it would be almost 10 times cheaper than coal. It isn't. So that number is very likely wrong.

I am not anti nuke, but I do get tired of the cheerleading that passes for analysis.

Best Hopes for fewer pom-poms and more pencils....

EROEI is not ROI. BTU != $

They aren't all the same. If they were, Canada would never throw away natural gas on the tar sands.

Life cycle energy and greenhouse gas emissions of nuclear energy: A review

Manfred Lenzen; Energy Conversion and Management 49 (2008) 2178–2199

The most popular reactor types, LWR and HWR, need between 0.1 and 0.3 kWhth, and on average about 0.2 kWhth for every kWh of electricity generated.

That suggests about 5. I'm a bit suspicious but this is a peer reviewed review.

About 3 kW-h (thermal) -> 1 kW-h (electrical), so that's more like 15:1.

Thanks, and herein lies a major problem comparing these outputs.

What exactly is the problem with the analysis at WNA and University of Melborne study? As I read it they're fairly verbose about the lifecycle cost of nuclear power.

One giant variable is which enrichment infrastructure you're using. Since most of the legacy enrichment is gasseous diffusion, it can warp numbers considerably.

Curiously, 15:1 is consistent with diffusion enrichment figure at the supposedly "pom-poms before pencils" website I initially cited. The 50:1 comes from centrifuge enrichment. According to Wikipedia -- perhaps not the most stellar of sources -- gas centrifuges make about 50% of the worlds enriched uranium.

I don't think it can be stressed enough all of these numbers are based on an extremely inefficient use of the fuel. IFR, LFTR and other technologies extract ~100x more energy from the fuel: so even if current nuclear sources are 5:1, we already know how to take it to 500:1.

Most of the academic literature I have read puts diffusion enrichment at 5:1. If nuclear power could reach 50:1 then it would be the cheapest form of energy in existence besides burning coal in a stove. Electricity would be cheaper than natural gas. It would be cheaper than unrefined crude. Neither of those are true. And truth is what we are after on this site.

Look, if I did a little experiment to measure the density of a block of lead and it came out lighter than the same volume of air, would you say "Good job Jon! You just overturned a thousand years of scientific measurements. Time to publish!" or would you say "Hmmm. Maybe you should go home and do those measurements again...."

We all have a bias in what we want to be true. The trick is to see past that to what is true. Lead balloons and dead ends don't help anyone. There are paper references in the link I posted and I would be glad to provide others. Send me an email. There is a lot to understand and the more eyes and brains the better.

If nuclear power could reach 50:1 then it would be the cheapest form of energy in existence besides burning coal in a stove.

You said this before, only to be promptly corrected by Dezakin (see above). Given that you completely ignored the correction, and the patronizing attitude ("We all have a bias in what we want to be true. The trick is to see past that to what is true."), I don't see much hope you'll read my correction either. C'est la vie!

I don't agree with Dezakin's position. If you want references I would be glad to provide them. Shoot me an email.

Most of the academic literature I have read puts diffusion enrichment at 5:1

My calculations based on kWh/SWU and SWU required for a fuel load indicate that gaseous diffusion is closer to 20:1 (5% overhead), and gas centrifuges are better by roughly another factor of 20 (0.25% overhead).

Hi Euan - IMO this is the key topic for energy.

Just an idea re: getting the 3rd dimension in - could a first stab be a time series of histograms with one graph per year for the next 10 years?

Each bar width could be the total no. of TWh/annum estimated as available from a given source. Vertical axis is as above, a percentage scale with the overhead on each source shown as the corresponding top slice off the bar. Ratio of slice shows the EROIE. Horizontal scale TWh/year.

Separate bar for each potential energy source ordered left to right by decreasing contribution and hence barwidth. Also suggest a bar for energy conservation (ie simple switch off/don't do) reduction in demand as an energy source(not sure about this one at the mo. - just floating it). For energy capital systems (PV/wind etc) the overhead could be loaded to the first year for construction and then reduced for productive years. For fossils it could be increased as they get harder to extract and exploit. Energy efficiency measures could use overheads appropriate to technology/material as noted by poster above (sorry window not open so cannot credit name). It also allows for sources to drop in and out of the mix as technologies come on/off stream.

Run the numbers for (say) ten years of estimates and plot cumulative net projected supply and projected demand vs. time on a separate line graph. The effect of energy conservation as a source means it cannot be shown as a reduction in demand but it could help to position it relative to other choices of technology - the width of the bars would help visualise its relative value. Scenarios could include (for example) contribution available from retrofit CHP with the overhead decreasing as the build and install energy offset is outweighed over time.

An alternative could be to produce it as a 3d solid chart, or surface, but I think this would be harder to read than a series of charts to the same vertical and horizontal scale.

Hope its of some use - sorry it's a bit halfbaked and/or nothing new.

Improvements in Life Cycle Energy Efficiency and Greenhouse Gas Emissions of Corn-Ethanol
Adam J. Liska, Haishun S. Yang, Virgil R. Bremer, Terry J. Klopfenstein, Daniel T. Walters, Galen E. Erickson, and Kenneth G. Cassman
-University of Nebraska—Lincoln in Lincoln, Nebraska

Ethanol-to-petroleum output/input ratios ranged from 10:1 to 13:1 but could be increased to 19:1 if farmers adopted high-yield progressive crop and soil management practices. An advanced closed-loop biorefinery with anaerobic digestion reduced GHG emissions by 67% and increased the net energy ratio to 2.2, from 1.5 to 1.8 for the most common systems. Such improved technologies have the potential to move corn-ethanol closer to the hypothetical performance of cellulosic biofuels.
Long Lake partners pioneer new oilsands technique. Nexen Inc. and OPTI Canada’s $6.1-billion technological gamble appears to be paying off as first production of sweet synthetic crude flowed from the partners’ Long Lake oilsands facility this week. hermal oilsands projects use a massive amount of natural gas to generate steam, which is piped into the earth to soften up bitumen and enable it to flow through secondary wells back up to the surface. The technology being pioneered at Long Lake would reduce the need to buy the fuel by running somewhat of a closed loop system. Break-even point for Long Lake is around $5 US per thousand cubic feet to make gasification worthwhile in an environment where natural gas is expected to average around $6 per mcf.

Laser enrichment should be commercialized by GE in 2012. It could be ten times more energy efficient than centrifuges for uranium enrichment.

Hybrid laser fusion (transmutation) - nuclear fission system proposed by Lawrence livermore as a followup to the funded National Ignition Facility.

This approach to fusion generates approximately 10**19 14.1-MeV neutrons per shot (about 10**20 neutrons every second). When used to drive a subcritical fission "blanket," the fusion neutrons generate an additional energy gain of four to ten depending upon the details of the fission blanket, providing overall LIFE system energy gains of 100 to 300. (EROI 100-300).

Transmutation is 3-30 easier for each metric of a required system compared to a full fusion only system.

Laser enrichment should be commercialized by GE in 2012. It could be ten times more energy efficient than centrifuges for uranium enrichment.

Waiting for laser enrichment to replace centrifuges is a huge mistake. We've been waiting for laser enrichment for decades, which is why we still have gasseous diffusion plants.

We should replace gasseous diffusion plants with a mature technology rather than waiting for this chimera.

We should replace gasseous diffusion plants with a mature technology rather than waiting for this chimera.

Um, isn't that exactly what is happening? France is building the George Besse 2 centrifuge enrichment plant that will replace its diffusion predecessor and the U.S. is building 3 new centrifuge plants to replace its coal-powered diffusion plant at Paducah. Meanwhile GE-Hitachi are planning to bring their Silex laser enrichment facility online sometime in the next decade, at which point virtually all commercial enrichment will be performed via centrifuge.

Sounds like a sensible plan to me. Transition to the mature, proven technology (which lowers enrichment energy needs by 25-50 times) while testing an even better one with a prototype plant. If laser enrichment proves successful it will enable more efficient use of mined uranium and make depleted and reprocessed uranium more economic, all of which bumps up nuclear's ERoEI.

The yellow arrow, pointing to ERoEI = 9 is intended to provoke some debate since we do not know with any certainty what the minimum ERoEI for modern industrial civilisation is.

This graph of ERoEI vs. percentage of energy available for society is utterly misleading. Pick the current ERoEI for crude oil as 25 and compare it to an ERoEI of 2. The respective energy returns for society are 96% and 50%. As the ERoEI declines from 25 to 2, energy production only needs to double to keep society supplied assuming constant consumption. Alternately, society could become more efficient. Carpooling with one other person would provide a large chunk of compensation for the apparently gargantuan decline in ERoEI. I can not see any basis for a threshold of 9 as the minimum needed to sustain modern industrial civilization. Because ERoEI is just one piece of the puzzle, no threshold can be determined without considering many other factors.

Surely the concept of EROEI can't be very relevant to people eg who flare gas or sell it or power for negative prices. "energy value" simply can't be isolated from market value (itself determined much more by quality, density and location of energy and not thermal units.)

I've been thinking about this since Euan first put this up.

What we really need is this: an aggregate energy surplus balance sheet of all current and projected energy assets broken into two categories: A)all sources of liquid fuels with their energy profit ratio multiplied by their scale (#bbls) and then aggregated over a time projection, and B)the same thing for sources of electricity. One big problem with E in E out analysis is energy quality - at some point liquid fuels will be more precious to society than an equivalent joule of electricity. Then we know what our true energy 'assets' are and can effectively work on liabilities.

Then, same thing for non-energy limiting inputs - in different colors. I will try and at least come up with a conceptual drawing of such on TOD and maybe others can fill in the details.

In effect a matrix of energy surplus, timing, quality (liquid and electric) and externalities. A lifetime of work for thousands - lets get on it...;-)

If you flip Jason's chart both vertically and horizontally, you get about the same shape as Euan's. And, I think, a pretty good prediction of what life would be like sliding down the energy cliff.

Does Less Energy Mean More Farmers?

Like this?

Qatar===> Nepal?

Fascinating. While that chart starts out approximating country vs energy use, one could also read it as energy-regime vs energy use - something I've been wondering about, the relation between levels of culture and technlogy and energy use. At 8-9% depletion, and three halvings of energy over the next few decades, that would put US about where Ukraine is now. Everyone else would move too, so that's barely a first approximation.

Another halving and US is into the realm of Mexico, Indonesia and so forth. A lot more peasants in the fields and flagrantly corrupt governments - if not military authoritarianism.

Presumably most of the countries along the left axis would slide back down the cliff and the cultural structures and institutions would have to morph accordingly. I can't imagine how Fannie Mae, Freddie Mac, SIVs and the whole world of FIRE might have to change. Along the downslide, the sunk investments will suck all sorts of resources - assets will in fact be liabilities.

Where do we lose our iPods? China doesn't make iPods for its own people. Nor does Ukraine. Seems to me we need to lose them now, so we can put the energies into renewables. Of course, that won't much help anyone to right of Japan in that chart. They all fall into the Olduvai gorge.

Clearly Nepal, at the very end of the pipeline, has to be a society built on dispersed solar. Their problem now, if one reads the news, is that they have started to use too much petro; it's not working.

cfm in Gray, ME

Yes, exactly what I was thinking. Both graphs are really energy surplus per person. On the down hill side, it might not be %population involved in agriculture, but %population involved in energy production (which would include agriculture).

The cheese slicer models show us the energy in the discretionary economy. Flipping Jason's graph might give us a way to interpret what life would be like with so little energy surplus spendable as discretionary income. Basically: very, very poor.

The 2050 chart assumes a 5:1 EROI (somewhere around assumed the assumed minima for EROIsociety).

You seem to be confused about what the above graph is showing.
Plotting any data having a wide range in values is going to give a hyperbola looking the same. This data would be more meaningful if plotted as reciprocals.

Its not showing energy used in agriculture! Its showing which societies can provide non-farm employment. Chinese living in cities certainly buy mobile phones and use the internet, but subsistence peasants only selling 10% of their produce probably cannot afford these things.

In general, societies that can provide non-farm employment can afford cars, electric appliances etc so use more energy, not necessarily the farmers using more energy for farming although at the extremes this would be the case.

If we have to use less energy in the future( rather than just substitute FF with renewables), the non-farm population will have to use less energy. Mobile phones, computers, iPods will be the last to go because they use very little energy, compared to SUV's A/C, air travel. A critical value is 2,000-4,000 kWh/person/ year. Below 2,000kWh the standard of living ( human welfare index) drops, above 4,000kWh doesn't seem to matter. If the US and Canada shut down ALL FF generated electricity they would have about 4,000kWH/person, could be a lot more than this in 20years if continue adding 8GW wind capacity per year.

Hi Neil,

I understand the graph very well, it is per capita energy usage vs % of people employed in agriculture. As a society gains a larger energy surplus, people can give the farmer more and more energy in trade for food. This allows the farmer to supplement his own labor with mechanical assistance. Eventually there are very few physical farmers (and a lot of diesel tractors).

The EROI graph would be very very similar if across the bottom was not EROI but a measure of surplus energy per capita and along the side was % people employed in the energy sector.

The blue area on the EROI graph is the non-energy parts of the economy. You can see they will decline to nearly zero as EROI falls. That happens because energy surplus declines to zero. That is exactly the same as Jason's graph where non-agriculture jobs vanish as energy per captia falls.

Nearly everyone in Nepal is employed in the energy sector (solar power collection via herding and agriculture). And we can see from Jason's chart there is almost no energy surplus in Nepal (if you don't own a farm or a herd).

I agree that wind etc can provide a high EROI source of power. How fast can it scale in a declining economy? We are about to find out.

iPods will be the last to go because they use very little energy

I'd agree with that IF nepalese had a lot of iPods. They might. Cell phone technology, for example, leapfrogs landlines and may - or may not - be more possible once the technology exists and assuming it can be maintained. What you neglect considering iPods is the huge emergy of the content. Without the content, no iPods.

cfm in Gray, ME

This chart makes sense to me. Given the need of a society to convert energy into food, a lower energy state means a higher proportion of society's population is devoted to creating food sufficiency. As food surplus grows in a society with higher available energy, more of society can be devoted to non-agricultural pursuits (ideally of the innovative type).

But if we can't bust this mold, the world of Hobbes is all we have to look forward to.

Looking at the efficiency of energy procurement is great, and I think that you should also look at the efficiency of energy use. For instance a EV can go roughly four times farther on a kWh of electricity from a wind turbine of PV panel than a conventional vehicle can go on a kWh of oil due to electricity having much greater exergy in that application than oil does. An inventory of energy use in different applications on top of what you've already done would yield some pretty interesting results IMO.

I think this would be very cool also. We could kind of trace the efficiency of use for major flows of energy kind of like the LLNL diagram. They clearly have data on current "lost energy". We would just need some methods to estimate efficiency gains.

Do you have a good source of well to wheel efficiency calculations comparing petroleum and electricity? If I remember correctly, Nick had some pretty good sources.

Let's talk about this for a second to try to capture some of the complications:

1. Electric cars and electric trains have less point to point travel range than petroleum powered vehicles. This means less economic utility. This utility has a value today greater than the cost difference between electricity and gasoline (or everyone would be driving an electric car). This drop in economic utility must be factored in as a reduction in the efficiency gain. We need to think about how to do that.

2. Electric vehicles typically have higher capital costs as well as lower performance. We would need to account for the higher capital costs in the efficiency calculation. This is pretty easy to do because we have the Mj/$ values for many different kinds of industries.

The energy flow trends shows why your "2050" flow diagram will not be accurate.
Nuclear, hydro and wind do not calculate "wasted " energy but KWh output so essentially not loss( small loss due to distribution). Their EROEI is actually of a higher "quality" because we are comparing them to FF where additional losses occur after the coal mine or well head. In your energy flow diagram nuclear losses appear to be shown but usually EROEI for nuclear calculates nuclear output as electricity( have data) not heat(no data).

Thus to replace the 40 exajoules of FF with electric cars, heat pumps etc, would only need a small fraction of this, perhaps 15 exajoules of electricity generated by nuclear, hydro, wind, solar. So if they have an EROEI of 10:1( appears to be higher than this) now, using FF inputs when the only outputs are electricity, the EROEI will be X 3 times higher using electricity inputs, because we are measuring EROEI on the basis of "energy used" to produce "energy" even if the input is FF energy having a 70% loss before providing useful work and the output is electricity having a <10%loss.

As far as electric vehicles having less utility because of lower range that's only relevant until the range exceeds travel distances required. Is a gasoline car less utility than a airplane? In any case range depends upon battery technology and will improve as batteries improve. Cars using lead/acid batteries can have a range of >100miles( greater than needed by 90% of trips). Interstate travel can use electric trains rather than electric cars, car/train transport as is done in Switzerland or hybrid fuel systems.

Hi Neil,

We agree this is an area worthy of study. And EROI guy has made a great start with the paper he published (linked in comments above).

It would seem true that electric vehicles are more efficient users of energy that non-electric. The question I have is why has humanity been willing to pay for that inefficiency? The market should have taken the more efficient path. So why non-electric?

Until we figure out what cost barrier prevented the arrival of electric vehicles in every OECD economy, then we don't have the whole answer.

I know that up here where it is very cold, heat pumps are not as effective as more moderate climates. I would be very interested if someone calculated the difference in energy usage for each climate band.

It would be great to do some kind of Mega Project kind of thing around energy efficiency.

Hi Jon,
You have raised a fair question;
"The question I have is why has humanity been willing to pay for that inefficiency?"

Until 2000, their was a surplus of oil, it didn't matter if the EROEI was 20:1 or 10:1.
In US gasoline was <$1 a gallon, most cars on the road today were purchased prior to fuel prices >$2 a gallon. During most of the oil age electricity has become cheaper and cheaper as technical improvements and economies of scale allow first kerosene for light, then oil for heat, then most stationary work to be replaced by electricity. Now NG heat is being replaced by heat pumps even though some peak electricity is generated by NG.
CO2 heat pumps apparently are fairly efficient even in Canadian winters, and wherever you live their are going to be spring and fall periods where heat pumps are 3-4x as efficient as electrical resistance heating even if they drop to X2 in winter.

As we start running out of oil, price will ensure its used where electricity cannot compete( air travel, remote locations,ships) or to keep the existing infrastructure( truck transport) working until it can be replaced( by electric rail). Just to replace all cars is going to take 30 years, but seems that oil will last at least 20. Just like 8-track players or vinyl, some old bits of technology have to be dumped before they wear out. Fortunately cars seem to have fairly limited life-spans unless really cared for by collectors.
The other alternative is that Detroit keeps making vehicles people don't want and we have draconian gasoline rationing, but then the vehicles will last too long and people will stop buying anyway. The next car I plan on buying I want to be able to drive for 20 years, so will wait for a PHEV, that way will be able to drive even with gasoline rationing.

In terms of range, people could still use, either via a purchase or rental, conventional vehicles and PHEVs, it's just that they would have to pay more for the liquid fuel they're using. In terms of economic utility, we could all keep conventional vehicles because they offer more economic utility, but given the cost, what's the point? We could all drive F-650s because they have more economic utility, but the cost is exorbitant for most. It's cheaper to drive a car and rent a pickup just like in the future it'll likely be cheaper to own an EV and rent a vehicle w/ longer range. Overall, it'll probably come down to EVs in the city and PHEVs in the burbs/country. There is also a limit to how much people will drive, regardless of how cheap gas is or isn't. Given that limit, as well as current tech, we could see EVs w/ 200 miles of range at highway speeds. They wouldn't be two ton pickup trucks, but considering 90+% of all vehicle trips are one or two people w/ minimal cargo, the drop in economic utility would be minimal. And naturally people can still use larger vehicles if they actually need them, they'll just have to pay the $5-10/gallon liquid fuel will probably settle at.

EVs have higher initial costs in limited production, but so does every other vehicle out there. Capital costs over the lifetime of the vehicle are lower, even at $1.50-2/gallon, mostly due to the decrease in maintenance costs. Yanking the engine, complex transmission, fuel system, emissions system, and so on, w/ hundreds, maybe thousands of moving parts and replacing it with an electric motor w/ a couple moving parts results in something that's much more reliable and easier to work on. EVs also provide more in the way of acceleration. For instance the Tesla Roadster, even w/ it's primitive pack (heavy) and pain in the ass management system (That's what they get for using old battery tech), can go from 0-60mph in 4s w/ only ~250hp. A Porsche 996 GT3 needs ~400hp to go from 0-60mph in 4s.

Each vehicle type has it's trade offs. In mass production, EVs are almost certainly cheaper to own and require less in the way of capital over their lifespan, even if they do have a higher purchase price. They are more efficient, can be powered from renewable energy, and have fewer externalities associated w/ their use. No need to be mucking around in the Middle East, no point of use emissions and far fewer lifecycle emissions, better acceleration compared to power, and so on...

Conventional vehicles are cheaper initially, although not over their lifetime, and can store more energy, so we can have much larger vehicles with greater range and towing/hauling capacity, although that comes at a cost. Since we're talking economics, overall it comes down to cost, both direct and externalized. The difference in economic utility is minimal given most use (one or two people w/ minimal cargo), and even if most of the fleet were EVs, we would still have conventional vehicles and PHEVs available for long distance travel or hauling, we just wouldn't be using a two ton pickup to commute to work every day hauling ourselves and a sack lunch. ;)

Hi Roflwaffle,

I have heard that EV's will have much lower mechanical costs. But it is my understanding they also have high batter replacement costs. Can you dig up some links to quantify EV numbers? I would be glad to help write up a piece on the idea. My email is in my profile.

What I mean by economic utility is that people clearly prefer non-electric cars world wide. There are no major electric car providers. I don't say that to bash electric cars. I say that because there *must* be some features of non-electric cars that cause them to dominate the market place. There is some economic value or utility that a non-electric car can provide that an electric car cannot. And we have figure that out and factor it into the cost.

As a simpler example: Suppose we are just talking electrified light rail versus automobile. It is clear that if you don't live next to a light rail line, you won't be replacing your car. So it is not just a case of comparing the efficiency of electrified light rail vs automobiles. A cost must be paid to either build light rail past every home, or there are many homes that won't use light rail. Either way, it cuts into the ability of electrified light rail to replace cars.

Something like that must be happening with electrified transportation or people would be rushing to buy them. We need to figure out what those limitations are and factor them into the calculation.

Off the top of my head, in mass production the best chemistry for EVs will probably be about $300-500/kWh, and one kWh of battery can store ~7000 kWh of electricity when just looking at capacity loss compared to discharge cycles. Taking something like the Chevy Volt as an example, the 16kWh pack would be ~$6500, and at .2kWh/mile, the pack would last ~550,000 miles before needing replacement. Of course this ignores aging, which impacts capacity as well, so at ~1.5% per year IIRC, it would take ~30+ years for the pack to be replaced due to aging. The minimal mileage would clearly be zero in the case of someone buying the car, then letting it sit for 30+ years, however at the average mileage per year an American driver clocks we're looking at somewhere around 250,000-300,000 miles before pack replacement is needed.

At ~$7000 for the pack, that's ~2.3c/mile. At .2kWh/mile and 12c/kWh, electricity is around 2.4c/mile, and combined we're at ~5c/mile. This is equivalent to a car averaging ~40mpg with $2/gallon gasoline, so even with gas prices where they are now I'd say that fuel costs over some time period are equal to battery replacement and electricity costs. The savings as you might imagine comes from no changes/repairs over that time period associated w/ the engine/complex transmission/emissions system/fuel system and so on.

Here's the pdf on capacity loss when cycling/aging. Grabbing A123/Dewalt packs off of ebay results in ~$1000/kWh, so before tossing in a mark-up for ebay, the seller, shipping, and dewalt, as well as all the other material not needed in the power tool battery pack and we're probably around $600-800/kWh IMO. In bulk from China, large format LiFePO4 packs from other manufacturers are around $350/kWh, but they also don't last as long as A123's stuff in terms of cycles. They do IMO gives a good look at what the base price of materials costs, and I imagine that once the patent B.S. for 'em gets resolved we could see something similar to what A123 produces for ~$300-400/kWh.

1)There is huge investment (hence commitment) in ICE production, and there continues to be by most major car manufacturers.

2)The ICE is very durable and does not require exotic materials to make it. Iron and carbon for steel/cast iron for blocks and crankshafts plus silicon/aluminium alloys for pistons and cylinder heads. 4 of the most abundant elements on earth.

3)Pre peak oil, limitless cheap, light and portable fuel source. As some one said above, if you have more fuel available than required inefficiency has no immediate consequence.

4)100 years of dedicated infrastructure construction to support 3)

Nickel, Lithium and cobalt (and other battery metals)are scarce and expensive by comparison and you will need 400kg of battery to come close to competing with a 50kg fuel tank for range. The outlay for this expensive battery is imposed on you from day one, the cost of fuel is progressive and if you don't use it you don't pay for it. The cost of running an electric car is based on no tax for the fuel. I dare say governments will change this tax "evasion" once electric cars start to deprive them of revenue.

These are only my views on why electric cars may never be affordable for the masses. I suspect in real terms, modern ICE powered cars are not as affordable as we have been led to believe. They are (or more correctly have been) bought on easy credit and look at where we are now as a result of the new car binge! The motor industry is in tatters.

There are no easy answers, I sure on that we can all agree. The 80/20 rule applies. the 80 bit has passed by with peak oil.

Regarding 2), ICEs are generally not more durable than electric motors. It's just a matter of complexity and physics. Hundreds of moving parts will almost always suffer more break downs than something with a couple moving parts. Since we also have to deal with the emissions and fuel system, most conventional vehicles end up being retired around 120k miles due to expensive repairs.

Unfortunately ICEs also require emissions systems and so on. The emissions systems have metals such as Platinum and Rhodium (~$1000/ounce), and anyone w/ an electric reciprocating saw can yank most cat converters. Not very common or cheap.

Lithium otoh, isn't too bad since the most promising chemistry only requires an eight of the lithium other common Lithium based chemistries require. At about a third of a pound of Lithium Carbonate per kWh, this means we would need ~5-6lbs of Lithium Carbonate per Volt-like vehicle produced. King's Valley alone has almost enough Lithium Carbonate to replace every vehicle in America w/ a PHEV like the Volt. Unlike oil, we can recycle Lithium.

In terms of infrastructure, we already have an electric grid, which is all we need for PHEVs. This will minimize oil consumption and reduce costs. Taxation is generally not done because EVs have far fewer externalized costs than conventional vehicles, so even if a government doesn't get revenue from mileage driven, they don't loose out on money from greater health care costs and fewer people working. That said, most costs in terms of wear are actually from heavy duty vehicles like tractor trailers, so for the past century or so, business use of public roads has been getting subsidized a great deal by tax payers. I have no problem if this changes and the tax payer actually pays for the wear their smaller vehicle causes, as opposed to paying for the wear of larger vehicles used by business.


I would agree ICE's are nothing like as durable as electric motors neither can they deliver such desirable torque characteristics, but they are durable in terms of the life of a vehicle. Most vehicles pass their econimic life with the engine and transmission in good order. Same would be true of electric motors, scrapped in perfect order. Cars de-value due to status rating not wear and tear. You argument is pointless!

ICE don't require emission systems to work, they are imposed by government and actually reduce the efficiency. Modern cars are blighted by electronics and the this is often the cause of an uneconimic repair and a good vehicle is scrapped as a result.

I'm neither defending the ICE or oil, read my post again!! The recharable battery (and fuel cell) was invented 50 years before the ICE. It speaks for itself.

We don't have an electrical infrastructure for EV use. Dream on, the UK has about 2% spare capacity. 30 million electric cars on the grid, I don't think so, kettles can bring us to maximum demand during commercial breaks.

I agree that most vehicles could be fixed for not too much money by someone knowledgeable, since it isn't just the engine/transmission mechanicals that tend to be the problem, but the complex emissions and fuel systems as well as accessories, and even basic maintenance. In fact, I would imagine that these days those present the majority of trouble. The problem is that unless most people can fix their own vehicles themselves, with essentially free labor, and find the lowest prices on parts, they're SOL. Not counting maintenance, which in and of itself adds thousands of dollars over a few hundred thousand miles.

Even a $25 oil change every 3000 miles is $2500, roughly a quarter of the cost of a new battery pack, over 300,000 miles. Toss in other wearables such as transmission oil changes/flushes, coolant changes/flushes, air filters, oxygen sensors, and so on, and even with routine maintenance, assuming nothing major breaks, we find that maintenance costs roughly equal battery pack replacement costs. Or to put it another way, battery pack plus electricity costs roughly equal gas costs for a 40mpg car at $2/gallon and maintenance is reduced, somewhere around a 3-4c/mile drop. This is of course assuming gasoline prices stay low at $2/gallon. If they go up again, the rate of savings increases dramatically. The current engine/complex transmission/emissions system/fuel system/etc and it's associated problems coupled with high repair costs are a big reason why cars are retired at ~120k miles.

We can have vehicles w/o emissions systems, but then the costs of health care from the huge increase in pollution outweighs any cost savings we may see from fewer repairs and/or greater mileage, although w/ most emissions systems these days the cost to mileage is minimal.

In terms of grid usage, in the states we have a ton of spare capacity at night, more than enough to charge a fleet of Volt like PHEVs given the average mileage per day seen. In CA for instance there is abundant transmission capacity. It's a shame that the grid in the UK is in such poor condition that it's always within 2% of capacity like you mentioned, electricity rationing must be common place, but if that's the case you should look into upgrading your grid.

None of your 4 points are valid reasons why ICE's will not be replaced by EV:

"1)There is huge investment (hence commitment) in ICE production, and there continues to be by most major car manufacturers."

At least for PHEV's the same investments will be used( body, wheels, ICE engine). A PHEV will require new investments as do all new models, and as well capacity to produce electric motors and batteries.
"2)The ICE is very durable and does not require exotic materials to make it."
Virtually the same for PHEV and EV; Li is not toxic, compared with lead/acidPre

"3)peak oil, limitless cheap, light and portable fuel source."
We are close to peak oil, but electricity is cheaper and has less limitations in expanding production

"4)100 years of dedicated infrastructure construction to support 3)"
except for oil producing infrastructure which is long past its used by date, same infrastructure for EV and PHEV, roads, fueling stations(will still need to pick up milk, add air to tires, wash windows) will still need some mechanical service( though less). We already has the electricity infrastructure and Ev's will actually add stability to grid, easy to drop off charging vehicles for a few hours not like dropping out TV or lights.

Looks as if all my points are valid to me then! PHEV use an ICE. I said post peak oil, implying we may be post now. Read my post again. Electricity for vehicle use is tax free (at the moment)

You have produced a questionable argument against Partypoopers points but I did not see him state that ICEs will not be replaced by EVs, nor did I see him defend ICEs. He simply stated a series of facts and then offered an opinion, primarily economic, as a response to a previous post.

Obviously, you are a proponent of EVs.

Please expound on and address all aspects of his post (e.g. lithium reserves) and then talk about true infrastructure requirements, not windshield washing stations, i.e. grid capacity and the fact that the energy has to come from somewhere.

EVs only have value as grid stabilizers if they are idle when the grid is under higher demand but the bulk of EVs will be idle when the grid has the least demand. Yes, EVs have the potential of providing load leveling, but please do not present it as a silver bullet. The people on this forum are smarter than that.

I respect your enthusiasm, but please do not morph his post into straw men.

These are complex issues here. I encourage you to explore further.


Thankyou for taking my post into context, you seem to understand my points. Looking at ideals, as many do, will not solve our problems. Hybrids are no fix, as the reply to my post seems to hope. In the UK at least, hybrids are not that popular and in most real tests do not compete well economically against diesels (despite the rising cost of diesel).
Unfortunately, its prospective profitability (which attracts investment) which also requires affordability that counts. I made the point that if the people can't afford a technology then there is no point in any body investing in it. I went further to question whether we can really afford current cars (ICE) without enless credit, and suggested we probably can't. All I can say is I won't be surprised if we see much reduced capacity in the automotive sector when we realise what is financially sustainable.

My pleasure Partypooper, although I think that yours is not an apt moniker. Perhaps "Realist" is more appropriate for you, (since Pragma and Pragmatist are already taken. ;-)

I have a paid-for house and money in the bank through technology, but in the process, I have learned its limitations.

We try to cling to BAU under different guises, but rather than doing more with less, the solution is to do much less with less. Due to MSM, the transition from "no limits" to a limited planet is difficult. Those that can not shift their paradigm will have a very bad day.

That said, I hope "The Picard" will arrive soon. (ref: Star Trek TNG for the young'uns)


Pragma, I am in a similar position, mortgage payment completed by technology and engineering, though the saving bit is proving a little harder, now the uk has 1% interest rates.

Had not time to reply to RalfW this morn. so here goes!

I work for a company that manufactures ac and dc motor drives and regularly work on test rigs for electric motors being developed for traction, so I know a bit about the subject. I also worked on developing battery vehicles for the uk coal industry, though the company I worked for at the time also made diesel powerpacks. What I can say is electric vehicles will not be simple and will suffer power circuit (IGBT) failures, control failures and the rest, just as industrial drives do. The motors will be almost certainly exotic permanent magnet servo type with rotor position (commutation) feed back to the drive, so though motors are simple, feedback devices can (and regularly do) cause the demise of their host.

Secondly, I do all my own car repairs including, in the past complete engine and gear box rebuilds, though cars built from the 80's onwards proved to have very long engine life due to much higher gearing. I drive the oldest cars I can that reliably take me around the country as my job requires, I would not have a hibrid as a gift. I did 30,000 work miles last year and similar the year before, totally trouble free in a £2300 diesel car.
There is plenty of information available to service and repair cars that are of 2000-2005 era. Things are getting much worse now, and even a hardened DIY car fixer like my self will eventually have to face the fact that car manufacturers can make their cars DIY proof. More good cars will go to the scrapyard beyond "economical" repair. Is this progress?

Thirdly, 120,000 miles is way off the mark for the end of engine life. I have two cars going strong, one with 132,000 and the other 170,000. Well in excess of 200,000 is not uncommon amongst my colleagues even for those with petrol engines. Most cars are scrapped due to lack of resale value or electrical faults not mechanical failure

Any vehicle that's repairable can be maintained, I have two petrol Toyotas with 190,000 and 245,000 miles and a diesel VW with 350,000 miles, but that isn't what most people have.

In the U.S.", the average age of a vehicle is ~9 years, which corresponds to ~120k miles at the average mileage per year in the states. As doable as keeping a car up is, most people don't because they don't do it themselves, and have to deal with extremely pricey repair costs.

In terms of inverters, older vehicles like the RAV-4 EV seem to have seen roughly one failure per one million miles, which is pretty good. Since inverter replacement is far less labor than, for example a head gasket replacement, the average consumer will probably have something that costs less to maintain w/ an EV compared to a conventional vehicle due to greater reliability and less labor required for repairs. Granted, inverters and other power electronics can fail, but the difference in how often they fail and how much it costs to replace them compared to all the other things that can fail on a conventional vehicle is pretty big. Overall, it comes down to complexity. Having many interdependent mechanical, electric, and possibly pneumatic systems results in something that is way more complex and is more likely to break down compared to a simple system, as well as costs more to repair due to higher labor costs and so on.

I suspect electric vehicles will suffer the same fate, CAN bus, coded door locks for example. Any failure such as this, which a dealer repair, will be sufficient to put an otherwise good vehicle onto the scrap heap for reasons of perceived econimics ; ie value of vehicle V cost of repair.

Depreciation is based on *repair frequency and cost, and I imagine an EV would depreciate slower than a conventional car, especially when they first come out since they still wouldn't be common, so the value of the vehicle versus the cost and frequency of repairs would be very different compared to a conventional vehicle. Granted, the dealer could still charge $1000-2000 to replace a fried piece of electronics or a busted door lock, but as long as the repair interval of those pieces doesn't drop substantially, it would be more than offset by less maintenance and other repairs and could be justified more given the lower rate of depreciation compared to a conventional vehicle.

*Hondas and Toyotas for instance depreciate slower than a comparable American vehicle, which is why my Toyota, even at 190,000 miles, is worth more than twice as much as a comparable Chevy or similar.

I agree with you to some degree, but depreciation is more complex than this. A new model can wipe the second hand value off and existing model for example (keeping up with the Jones' syndrome). Repair intervals are not always mileage related either. A car doing a school run will suffer a different wear pattern, door locks, steering and suspension for example, than a taxi or someone like me that tends to do long distances in a single journey on a long straight road.

Your second point may be down to fuel economy (direct running cost), rather than repair bills. I would have thought (only a suggestion) large engines in American trucks would have a long life. In the uk, economical cars and those with the correct image (eg VW TDI Golfs and Passats)retain their values well, while other pefectly reliable cars are practically worthless secondhand.


You suggest somewhere above about oil changes every 2-3 thousand miles. This is not the case, 12000 mile for diesels and 15000 mile for petrols, oil changes have been specified for years now. My last diesel was a 1994 car and was the last year that model was made and that had oil change intervals at 12000 miles. There was nothing wrong with the engine at 153,000 miles when I scapped it (due to body rot). These days some cars now have 30,000 mile service intervals, thats 10 times what you are suggesting. Gearboxes are "fill for life". so no cost here at all.

The average around here seems to be ~4-5k for petrol and ~10-15k for diesel, which is almost always synthetic AFAIK. Granted, for a newer petrol car like a Prius, that has a 5k mile oil change, there would be a reduction in cost compared to my older vehicles, but that's still $1500 over 300,000 miles. Diesels w/ synthetic have twice that interval (or more in the case of heavy duty trucks) but the oil change also tends to cost about twice as much. Most people can safely ignore a manual gear box since they tend to junk the car around 120k miles anyway, but that doesn't make it a maintenance free item, at least if the driver wants to keep the vehicle up. ;) Of course this ignores that most vehicles are automatics, at least on this side of the pond, and require periodic fluid changes and possibly flushes. And like you mentioned wear i also a concern, so someone in an urban environment with frequent cold starts would have a lower oil change interval, and ironically would also benefit more due in terms of fuel savings due to no idling, and not getting hit by throttling losses. It's almost a certainty that the last segment of vehicles to go would be those used for long distance high speed commutes, since they tend to exhibit the least amount of wear overall and the engine tends to be operating efficiently, but just because there is a specific segment of vehicle users that wouldn't benefit as much doesn't mean that manufacturers should make EVs for other segments.

In terms of cost, at $6 per man sized gallon the the U.K. there's no reason to even bother with a comparison of maintenance costs. Even a Prius at 60mpg would cost a little less than twice what an electric costs when comparing battery costs/electricity to petrol costs. That alone would pay for a couple of battery packs. Toss in the reduction in maintenance costs, even with only ~$1250 spent on oil changes as opposed to $2500, and so on, and an electric is still cheaper on average. In the U.S. it's a lot closer because petrol prices are a little less than half as much, but even then electrics are still at cost parity.

Granted, the point wouldn't be to market EVs to suburban commuters over here clocking 150 miles per day at 75mph, since there would be little if any cost benefit for 'em, but instead to offer it to urban commuters who could save a bundle because most of their commute involves idling in traffic for three hours a day in order to go 60 miles. In other countries, higher fuel prices make the difference more pronounced, at least for new car owners. It's almost always cheaper for an old fart to run a couple decade old diesel on used chip oil, but that as I'm sure you're aware isn't the majority by a long shot.

A new model can hurt an older model's value, but in terms of EVs I doubt it will significantly since they'll be fairly rare for a while, and by then oil prices may be high enough to make any comparisons moot. In terms of engine, life, it mostly depends on the make/model. SBCs tend to have about half the service interval of something like a 22R before they need a rebuild.

Automatics are not common in the uk, at least not on the Mr Average type cars. Some larger cars such as V12 "Jags" were exclusively automatics.
Diesels here have always had shorter service intervals than petrols. The Austin Metro which was launched in 1980 had 12000 miles service intervals and diesels followed in 1986 with the "Perkins Prima" direct injection diesel engine. Vauxhaul had their petrol's intervals at 9000 during this period. My next door neighbour has a 2005 Renault and that is 30,000.
I am very surprised the Prius has such short intervals, that's a retrograde step. The Prius is not that common in rural Britain where I live, there are very few around and Ford models alone dominate by a long way. I don't know the exact figures, bur diesels did account for about 50% of new car sales, however, this is not many cars thesedays!
I'm not sure how governments would deal with taxation if/when electric cars become popular, but i'm sure they will find a way. We have been lead down the garden path before on this one, first diesel was cheap to encourage people to swap to diesels, now its over 10% dearer than petrol, then LPG was, and still is to some degree but its on the rise, but its price is rising and its calorific value is lower. Taxation is used as a legalised method of coercion (a beating stick). Taxation is a very high proportion of fuel costs in the uk. We get taxed (VAT)on tax (Duty).

The motors will be almost certainly exotic permanent magnet servo type with rotor position (commutation) feed back to the drive, so though motors are simple, feedback devices can (and regularly do) cause the demise of their host.

On the contrary, the motors are much more likely to be induction motors, requiring no position feedback of any kind.  The drive can do all the required sensing by measuring voltage, current and phase angle.  This also simplifies and cheapens the motors.

Open loop control of induction motors is comparatively poor and flux vector models don't work well at low speed. All applications requiring any sort of dynamic performance or high stability low speed torque use closed loop control, which requires rotor speed feedback from an encoder or resolver, though not position.

If maximising efficiency is an issue then permanent magnets will be used, as they are for high performance traction motors. Induction motors require significant magnetising currents which result in higher copper losses. Permanent magnet motors require no excitation and operate at unity powerfactor.

As for your other three questions you tell me! The tesla boasts a 160 mile range, so to reduce this to 40 is some feat. Try reducing your fuel consumption by a factor of 4 in your VW TDI.

You can't charge lead acid batteries at that rate without damage and there are no sockets on the roadside to my knowledge. You would need 4 tonnes of lead acid battery to equal 50 litres of diesel.

I've seen the induction motors on locomotive wheel trucks.  This is perhaps the ultimate low-speed torque application.  I didn't see anything resembling a position sensor on any of them.

Permanent magnet motors cannot achieve the flux density of iron.  Induction and switched-reluctance motors can be smaller than PM motors for the same power, and require none of the rare-earth elements for the magnets.  As for efficiency, if the Tesla can get 200 Wh/mile energy consumption, that's good enough.  We need lots of them and we need them cheap; we can worry about the last 5% later.

The tesla boasts a 160 mile range, so to reduce this to 40 is some feat. Try reducing your fuel consumption by a factor of 4 in your VW TDI.

You mean, increase my fuel consumption by a factor of 4.  That's easy; all I have to do is climb a hill at low speed with the torque converter bypass open.  I can go from 26 MPG to 6 MPG on the same hill without even trying.

Hard driving in gears 1-3 will burn even more energy in the torque converter.  At max fuel feed in top gear, my car gets about 14 MPG instantaneous.  I can get upwards of 35 MPG very easily on the highway, so all I have to do to raise fuel consumption by 150% is run pedal to the metal even with the converter locked up.  You know, like they do on Top Gear?

You can't charge lead acid batteries at that rate without damage and there are no sockets on the roadside to my knowledge.

Lead-acid batteries deteriorate just from sitting.  Examining Commuter Cars' test of battery charge algorithms (which boosted cycle life to ~700 cycles), it's obvious that oxygen recombination is an enormous factor.  The fast-charge algorithms use discharge pulses to remove oxygen from the negative plate, reducing the oxygen problem in the first place.

You would need 4 tonnes of lead acid battery to equal 50 litres of diesel.

Assertion unsupported by figures or references.  Questionable relevance, too; if the application only needs 1/2 ton of batteries, who cares how much diesel it would take?

Assertion unsupported by figures or references.

Correct! but its supported by basic science which is good enough for me. You can start your sums by assuming 10kWhr/litre (0.8kg) for diesel then weigh a 70 amp*hr lead acid battery, which can release half its capacity over a 1 hour rate, the rest falls into place quite nicely without references. Its junior school maths. (70 amp*hr at 12 volt is 0.8kWHr). The Prius battery weighs 45 kg and is 1.7 kWhr. Toyota, I believe only allow 40% discharge, to provide acceptable life, which allows about 2 miles of travel. For 500 miles of travel I use 40 litres, which by extrpolation would require a battery of 11 tonnes. Take your pick.

1.6 tesla is about the working limit for electric motor steels (some power transfomers operate close to two tesla, but their construction allows grain orientated steels to be used), rare earth magnets can exceed 1 tesla. In addition because there is no need for slots to take windings, there can be more active volume of magnetic material. Pemanent magnet servo motors have the best dynamic performance and are used for this reason despite their high cost.

Unless things have changed switch reluctance motors have a lousy power factor, poor torque characteristics (ripple ans noise) and require position feedback as well. That is why, despite all the hype, power tools still use the good old ac commutator motor,

How often do you drive 500 miles?  Besides, standard lead-acid batteries couldn't propel a vehicle 500 miles; they don't contain enough energy to move their own weight that distance on rubber tires.

The Tango gets 40-60 miles on a 988 lb lead-acid battery pack.  That's more than sufficient for most people's commutes, and charging at work would make the average commute a snap even with heat and A/C requirements.  (They're not using PM motors either.)  Slightly advanced batteries like Firefly Energy's carbon-foam lead-acid would increase the range and cycle life while slashing the weight (perhaps not the best thing in a ballasted vehicle like the Tango, but it might allow more volume to be devoted to active material).

These things are more than good enough for today.  We can start building now, and worry about improvements later.

"but I did not see him state that ICEs will not be replaced by EVs,"

his statement was;"These are only my views on why electric cars may never be affordable for the masses."

"Please expound on and address all aspects of his post (e.g. lithium reserves) and then talk about true infrastructure requirements, not windshield washing stations, i.e. grid capacity and the fact that the energy has to come from somewhere."

Roflowafle gave a good answer to the Lithium question( has been covered in many articles in EV world).
As far as infrastructure goes service stations and dealerships service are major parts of today's infrastructure as well as highways, bridges etc. The entire grid and electricity generating infrastructure is also major, but the additional energy required can be mainly met by the existing infrastructure since most charging will be done at night when there is surplus capacity.
"EVs will be idle when the grid has the least demand". ???
That's when they will be using electricity to re-charge

The only part of the oil based transportation infrastructure not used by EV will be oil production, refining and air transport.
The additional energy has to come from either NG, Coal, nuclear and renewables. We are at or close to peak oil, but not at peak nuclear, wind or solar. Most NG is used for peak ( not a big use for re-charing EV's.). To develop more hydro, wind and solar, will require a massive additions to infrastructure. Perhaps 1-2% of GDP for 20 years. The US seems to have a new administration anxious to spend on infrastructure, to use surplus industrial capacity and labor.
Do you have a better suggestion on what infrastructure to build?


You seem to suffer word blindness. If you read my post again I also stated (three times including this post) that ICE cars may not be affordable, and that only easy credit has made them so.

I fill my car with fuel when I like (or need to) not when it suits the grid. What do you do if your battery goes flat? sleep in the car! Also it has also occurred to me what will supply the heater? modern cars have at least 10kW of heater output and in the uk at the moment its very much required as it will in other cold climates. The more I think about electric cars the more I relise those who think they are a silver bullet are cooking the books in their favour.

An EV has waste heat from the electronics and the motor for cabin heat; if these units are liquid-cooled, they can fit almost seamlessly with standard automotive HVAC systems.  A pure EV may be a commuter car, and not expected to run long distances with climate control running.  Something like the Tesla is clearly intended to be more than that, but if there's sufficient infrastructure to charge such vehicles on the road, topping off every so often while stretching legs wouldn't be a big issue.

If the vehicle is a PHEV, cabin heat isn't an issue.

EP,The only thing that suprises me is how long it has taken you to reply! The tesla takes 16 hours to charge according to Top Tear, thats more than a leg stretch. They flattened it in 40 miles as well. Its back to the drawing board as far as I am concerned.

If EV's are 90% (or so) efficient, as many claim, there won't be much waste heat and in traffic jams such as the 2 hours it took me to get out of London recently I would have frozen to death because there would be virtually no waste heat.

Even a diesel uses about a litre/hour during idle, that gives a nice 5kW waste heat into the water jacket, the other 5kW out of the exhaust to warm pedestrians. God bless inefficiency. On idle, in cold weather, a diesel will not support full heater output in many cars, including mine.

I wouldn't say it's back to the drawing board. Just that the roadster is more of a Monte Carlo cruiser as opposed to a track car. Different strokes for different folks. If someone wants something fast they can flog at the track and fill up/recharge quickly, they'll go for a Porsche (or similar) that can do 0-60 in 4s. If they want something that costs less to own, still goes 0-60 in 4s, and isn't meant for track duty, then they can go w/ a roadster or similar.

Granted, it isn't all peaches and cream, for instance a Porsche with a 10+ gallon tank would only go ~40-80 miles on a track, and the decision to push the roadster aggressively resulted in the use of Lithium Cobalt cells that can't be charged as quickly as the Lithium Iron Phosphate cells which seem to offer the best bang for the buck these days. I'd guess that w/ a modern battery tech a 220V outlet could recharge the roadster in less than half the 16 hours required currently.

It really comes down to what the consumer wants. If they want a quick boulevard cruiser that's cheaper to run, and can be powered by renewables, but takes a while to fill up, they can pick the roadster. If they want something more suited to floggings on the track and quick fill-ups, but is more expensive, they can nab a Porsche or similar. And if they're IMO really clever, they can grab a roadster and use the tens of thousands of dollars they'll save to build a proper track car that'll walk all over anything else they could've nabbed for ~$100+k. ;)

As for climate control, that's all the more reason to have descent insulation. Using poor insulation to justify inefficient energy use is IMO as silly sounding when talking about autos as it is when talking about buildings.

The tesla takes 16 hours to charge according to Top Tear, thats more than a leg stretch. They flattened it in 40 miles as well.

Two, no, three questions:

  1. Do you expect Tesla's LiCoO2 battery chemistry to be used in mass-market EVs?
  2. Do you expect low charging rates to be the norm for a transportation system with a large fraction of EVs?
  3. Do you drive like they do on Top Gear?

If EV's are 90% (or so) efficient, as many claim, there won't be much waste heat and in traffic jams such as the 2 hours it took me to get out of London recently I would have frozen to death because there would be virtually no waste heat.

If you had a small, cheap EV which carried 10 kWh of lead-acid batteries and used 1 kW to heat your seats, steering wheel and keep the glass clear, you'd have gotten out of London using only 20% of your battery capacity for heat.  The Tesla would have used a far smaller fraction.  You probably wouldn't want to sit for more than about 2 hours anyway, and there have long been fast-chargers for lead-acid which can bring them to 100% in about 15 minutes.  This is a rather small problem if properly handled.

Most US, Australian and UK families have probably had 5-10 cars over 2-3 generations. So which ones were not affordable, the last, all of them?

"I fill my car with fuel when I like (or need to) not when it suits the grid"
This is a silly objection to a slightly different technology.
If you have a PHEV or EV you will probably need to charge it overnight at home when the car is parked. When else would you like to charge it? Not when driving!, perhaps at a parking station( at a cost). Overnight off-peak will probably be the cheapest option, but some will pay more for "convenience" just as they pay a lot more for groceries at a 24 hr convenience store than at a supermarket.

"What do you do if your battery goes flat?"
same as you do now with an ICE vehicle, if you run out of fuel or have a flat battery; roadside-assistance.

The issue of providing heat in winter is very valid. I think for this reason PHEV's will be around for a long time in colder climates. In Canada, people heat their car engines and batteries overnight with electric heaters using mains power. This could be beefed up so that the engine was at 90C in the morning. It may be necessary to run the ICE engine for short periods(2-3 mins) during a winter trip to keep coolant warm( and also re-charging batteries). In colder parts of Canada the radiator is blocked with cardboard to prevent cold air entering.Other solutions are electric defrosting in all of the windows( very useful in Canadian winters) In any case a PHEV is going to be using a lot less fuel over the year even if the ICE engine runs a little more in winter.

"The more I think about electric cars the more I realize those who think they are a silver bullet are cooking the books in their favor".

We have had electric cars, fork lifts, golf carts etc for 100 years, we know they work, but are not as convenient as ICE powered with cheap and abundant oil based fuel. Sometime after peak oil, gasoline and diesel will become much less available and much more expensive. Many people may have to stop driving,and use mass transit only, some will be able to afford to drive ICE vehicles such as hydrids, while PHEV's and EV's offer a realistic possibility for many people to have the mobility provided by a private vehicle even if they cannot afford to use it to drive 1,000km trips. Fortunately, overnight charging will allow a more stable grid, especially if a lot of future power comes from wind energy, as is likely in US, UK and Australia.
Kerosene lamps were not replaced by electric light because electric lights were more portable or cheaper to install.


This whole argument is about why ICE's have not been replaced by EV's. The answer in short is cost and convenience. I am well aware of peak oil and problems it will bring, I am also aware electric cars may become a necessity in the future, but I maintain my original reasons for it not happening at this moment in time. I also will take some convincing they will ever be a like for like replacement for ICE, and we will have to change our habits to suit the avaiability of energy, but folk arn't going to do this without a fight and the ICE will fight on to the end.

If you run out of fuel in an ice you can have fuel delivered in a "can" and off you go, even diesels self bleed these days, I think this is a silly comparison. ICE's don't degrade in performance when the fuel tank is close to empty, they just stop when it is!

We do have electric fork trucks and they are used for because they are clean, and only for that reason. The battery is usually lead acid and used as part of the truck's ballast. They are a pain in the arse. You have to have at least one spare battery pack (plus charger) per shift (more for heavy use) and a handling system for battery changing routine. That is why many highbay wearhouse installations have "pantographs" and food factories have turned to propane where a free moving vehicle vehicle is required to operate indoors. You are correct to suggest they are not convenient, but they have a niche market all the same.

Almost forgot, as for sources, here's a 1996 RAV-4 EV that uses ~400+Wh/mile at the outlet. The exact same thing w/ a conventional drivetrain according to got 26mpg (old EPA). Gasoline has 36600Wh/gallon, so at 26mpg the conventional vehicle uses about 1400+wh/mile. Not counting all the energy needed to extract the oil... we're at ~3.3 times the oil energy needed compared to renewable energy. Toss in current battery tech, Lithium Iron Phosphate specifically, and we would bump up the efficiency of battery charging/discharging from the ~80% that lead acid is at to the 95+% of LiFePO4 and increase the spread from ~3.3:1 to a shade under ~4:1. Arguably we could increase charging efficiency a bit, but that's not where the biggest difference comes from.

Looking at oil produced in the U.S., California specifically, we can see that...
The high-energy intensity of the oil extraction operation makes this industry the 4th largest user of electricity and the highest consumer of natural gas in California. Annually, the oil extraction industry uses 3,846 million KWh of electricity 2,910 million Therms of gas.

A therm of natural gas is about ~29+ kWh, so to extract ~300+ million bbls of oil per year we use ~84+ billion kWh of energy from natural gas and ~4 billion kWh of electrical energy. A barrel of oil equivalent has ~5.8 million BTU or ~1700 kWh. So in order to extract ~500+ billion kWh of oil energy, we use ~84+ billion kWh of other energy, specifically from natural gas and electrical energy from other sources, so right there, not including refining, we see that oil's EROEI in CA is ~7:1.

Looking at refining does not improve the situation for oil...
Petroleum refining is the number one consumer of energy in California's manufacturing sector. In 1997, the industry consumed 7,266 million KWh of electricity and 1,061 million Therms of natural gas.

Googling shows that CA refines ~2 million bbls of oil per day, so ~700+ million bbls of oil per year. This requires 29+ billion therms of natural gas per year and about 7+ billion kWh of electricity per year. Assuming that we get ~90% of the energy back as distillate, gasoline, kerosene and so on, not counting the stuff such as we get 1,070+ billion kWh of energy from oil's refined products and input about 36+ billion kWh of energy, so the EROEI of just refining isn't too bad at about 30+:1. This is, generally speaking, the upper bound for what oil's EROEI can be considering it's current use. Assuming that everyone in the Middle East didn't need any energy for extraction or transportation would result in this EROEI given it's current use.

Anyhoo, tossing in refining in CA puts oil's EROEI at 5-6:1, after including transportation. Assuming energy free extraction and transportation in other countries and we find that at most oil's EROEI given current use is around 30+:1, right up there with thin film solar panels. Toss the difference in EROEI on top of the already wide difference in energy use, and we can see that in terms of energy, and probably total cost too, renewables in California specifically, and probably most of the U.S., combined with EVs, would be a much better investment than FFs in many (probably not all) applications. We have solar and wind power, at an EROEI of ~20:1, compared to oil at ~5-6:1, on top of EVs using a quarter of the energy conventional vehicles use. Overall that's a ~10-15:1 difference in usable energy. In CA, an electric RAV-4 would only require roughly 1 kWh of electricity for every 10-15 kWh of oil/natural gas/a wee bit of electricity a conventional RAV-4 would need.

That's a huge difference, and puts the renewable build up in context given this application. Like I said before, every application is different and comparing them would make for some interesting results IMO.

This is bullshit. Sorry. But it is. "Temperate latitude biofuels" don't have lousy EROEI. I've done proper calculations on temperate biofuel (ie "firewood"), and the EROEI is over 200, if you use a chainsaw and a small-scale forwarder for bringing it out of the forest. Using a harvester and a full scale forwarder the EROEI drops to about 50, but if you do it the pre 1950 way, ie handsaw, axe and horse you get EROEI over 500. Assuming that you only use the horse in winter, and thus just waste all the summer feed, when you in reality will use the horse for other things the entire year. And eventually the horse will get old and provide you with enough meat for the family for a year.

On the other hand, you might have meant ethanol from temperate latitude wheat, by having "temperate latitude biofuels" in your graph.

You know what you can do with firewood? Chop it into pieces and fuel a car (or a forwarder for that matter) using a home-built producer air pre-burner. EROEI will drop to about 1/3, ie even 50/3=16.67. Was done when Sweden were isolated during WW2, but then it was EROEI 500/3=166.

If you were rich enough to have a horse you likely would need a pack of dogs to help protect your wealth so they could eat your old horse while you managed a little better fare ;)

"Temperate latitude biofuels" don't have lousy EROEI.

Please provide peer-reviewed studies so that we can examine your claim's validity. Euan's numbers fit nicely with those we know about existing ethanol and biodiesel techniques. Your example of firewood is interesting (I also harvest and burn firewood), though it's scaling to a much larger population is rife with much higher additional transportation energy costs, resource availability, unacceptable levels of pollution, and conversion in large multi-unit dwellings.

Oh, is it? About 20% of Sweden's total energy consumption is from biofuels from the forests. Easily scaled, easily transported, and burned in cogeneration plants for about 45% electricity and 45% district heating for large multi-unit dwellings, at fully acceptabe levels of pollution, of which we have some of the highest standards in the world. Or for that matter, sometimes burned in plain district heating plants for just 90-95% heat generation.

Oh, and we only harvest about 90% of the annual growth in the national forests (out of which a minor part goes to biofuels), so there is not risk of overshoot.

I have a stack of leftovers from this winter's cutting in the forest, treetops, twigs and branches here on the farm waiting for pickup by a district heating company. About enough energy for heating a 20-household multi-unit dwelling all year, including tap-water.

This is perfectly ordinary here in Sweden.

Actually, about 10%.

fully acceptabe levels of pollution

What do you call perfectly acceptable levels of pollution from an energy source, specifically?

CO2 and H2O. NOX scrubbers. No soot or ash into the atmosphere. The ashes from biomass power plants in Sweden are returned to the forests as fertilizer.

Out of 1828 PJ of energy in Sweden 2007, 414 was biofuels, ie 22.6%.


(Alt 2 in the table is considering the net electricity generated by nuclear, while Alt 1 includes the waste heat from nuclear power plants, and is not relevant, but in that case biofuels would be 18.4%).

The EROI of potatoes is 30:1. The relevant issue is scalability, which is EROI TIMES the SIZE.

I wrote Energy and Time about the tradeoffs between EROI and time - there is much academic literature about this starting with Times Arrow from the 1950s.

And biomass is very low EROI and once it scales there are very large externalities.. In the analysis Home Heating with Wood, I showed that the annual growth in wood would account for 5-8% of USAs home heating needs, under existing technology - and that assumed no use for furniture, housing, plywood, etc.

Looking at this graph I see that nuclear power has a very low, ~4.5, ERoEI. The note at the bottom indicates that data for this number comes from a paper by M. Lenzen, (Life cycle energy and greenhouse gas emissions of nuclear energy: A review). Does anyone have a copy of this paper as I don’t want to pay Elsevier $ 31.50 for a copy. The abstract for this paper has the following sentence.

The most popular reactor types, LWR and HWR, need between 0.1 and 0.3 kWhth, and on average about 0.2 kWhth for every kWh of electricity generated.

As most nuclear power plants have an efficency of 30-34% which would indicate 3 to 3.3 kWhth / kWhe it appears that the data in this abstract is in error, and low.

Looking into some of Mr. Lenzen’s references for this paper I see he has taken some of his data from the Storm van Leeuwen paper,(2005). This paper has many errors both large and small. Virtually all of these errors make nuclear power look less viable, .
From a post Nate Hagens made one graph gives results for ERoEI for nuclear. It would appear that if you throw out the high and low as suspect you get a ERoEI of about 20. New reactor dsigns like the LFTR should have a much better ERoEI than PWR, and BWRs due to there low pressure loops, lack of fuel fabrication costs and gas turbines.