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Projections regarding the total amount of energy available globally between the year 2007 and the year 2200

If this projects until 2200 why isn't fusion power included at least as a plausible estimate. And how exactly does solar power peak and decline? In 2030? What exactly happens to the Sun in that year that suddenly drops off the power output? Does this refer to the ability to manufacture panels? Because we certainly aren't going to run out of mirrors and salt.

It wouldn't take that much to do all of this with solar already.

Honest questions. Not trolling. Just not getting the peak in solar.

Sorry to be redundant, but if the energy is not exported, it can't get to importing countries. I think that this is the fundamental mistake that most energy analysts are making.

Following is a copy of a post on the Drumbeat thread, showing the ELM versus a real life case history.

Export Land Model (ELM) Versus the Indonesia Case History

Indonesia was very similar to my ELM, since Indonesian consumption was about 50% of production, at peak production.

From peak production to the final year of net exports, the ELM shows a decline rate of 28% per year, although the year over year decline rate accelerates with time.

The decline rate in Indonesian net exports from 1996 to 2003 was about 30% per year, but as the ELM suggested, the decline rate in net exports accelerated with time, although they did show a one year increase from 1997 to 1998, because of a slight increase in production and a decline in consumption.

The ELM assumes a 5% decline rate in production and a 2.5% rate of increase in consumption.

From 1996 to 2003, Indonesia showed a 4% decline rate in production and a 4.1% rate of increase in consumption. From 1999 to 2005, Indonesia showed increasing consumption. I believe that their consumption declined in 2006.

The year over year changes in net exports were as follows ELM/Indonesia:

1996: Peak Production
1997: -13%/-16%
1998: -14%/+7%
1999: -17%/-16%
2000: -19%/-20%
2001: -23%/-32%
2002: -30%/-50%
2003: -39%/-73%
2004: -65%/Net Importer
2005: Net Importer/Net Importer

This is what my simplistic ELM suggested, to-wit, that the decline rate in net exports will accelerate with time.

IMO, the problem that exporters will have, in trying to curtail domestic consumption, is that cash flows from export sales will, at least initially, be increasing even as exports decline--because of rising oil prices.

Export Land Model:
http://static.flickr.com/97/240076673_494160e1a0_o.png

BTW, the reason that I chose a relatively high production decline rate for the ELM (5%) is that so many of the top net exporters are, based on the Hubbert Linearization (HL) models, at relatively advanced stages of depletion--especially the top 5 (accounting for about half of total world net oil exports).

Good work.

I see a modelling mistake in not including some factor for the "Law of Receding Horizons".

Since Coal, Nuclear and Oil sands are apparently making up the losses for conventional oil. Coal and Nuclear are not liquid fuels(discounting CTL), and the production costs are skyrocketing ALREADY for all three of these resources.

It may be difficult to model these effects, but without them, a pure capacity projection post-oil peak, is possibly flawed.

While I think it is a great eyeopener, I think the reality is that PEAK ENERGY is less than a decade away.

Chris,
- Check BP Statistical Review of World Energy 2007 for gas energy numbers. They are higher than your source, and comparable to known oil reserves.

- The nuclear sources you use apparently don't count for advanced fuel cycles. It is unreasonable to assume that future generations won't develop a workable breeder design, and fuel reprocessing technology. You should find there are about 500-1000 years of uranium to provide current total demand of ~15 TW.

- Your solar assumptions are just wrong. Check Stirling Solar and other CSP suppliers for EROI and cost estimates.

- The world can indefinitely sustain 6 billion people.
Just not this 6 billion. It seems to me that an advanced culture of nuclear/solar physicists capable of maintaining a renewable energy/recycling infrastructure would also be capable of using birth control. The challenge is to start teaching kids the science necessary (and stop teaching the superstitions)to develop such. Our leaders have no intention of doing this for us.

Your "Optimistic Scenario" fails to consider many of the measures that I have been advocating for the USA. i.e. much greater increases in efficiency and much higher rates of increase in renewables "while we can".

R-40 to R-100 levels of insulation (depending on local climate) for all new construction, with a move to ground loop heat pumps and solar hot water heating (some space as well).

Retrofit existing construction to a good % of those levels. Tankless gas hot water heaters where solar is NA.

Maximum buildout of Urban Rail with resulting TOD effects.
Shrink travel demand and transform VMT to walking, bicycling, NEVs ( http://www.gemcar.com ) and Urban Rail.

Make electrified rail the dominant form of intercity freight and majority of passenger travel.

Make renewables 75% of North American electrical grid and 25% nuke (or 70/30 or 67/33).

Do likewise elsewhere.

Best Hopes,

Alan

Chris: Great post- an overview of the global energy situation is always useful. With all the talk of solar, it is always shocking to be reminded of how tiny its contribution to global energy currently (1/290 that of oil).

It would be interesting to me if you took a look a how your calculations change if you include a 19% growth rate for solar and a 28% growth rate for wind. Expected short term growth rates (few years) are higher than these figures since costs for these sources are falling while costs for alternatives are rising. A simulation with growth rates around 60% would also be interesting.

Thanks,

Chris

The underlying assumptions are make believe.

Garbage in and garbage out.

There is no reason for nuclear power to peak, especially no reason for it to decline to almost nothing by 2050.

=====================
http://advancednano.blogspot.com

Not mentioned is the possibility that exporters will no longer see a need to short the market. Where is the incentive to increase production in a rising price market? That's like trying to convince people to sell their stock when the price is rising. Unless the price is set to fall... thus a rising price, self fulfilling feedback loop - house prices anyone? - can set in, and maybe already has. If demand destruction doesn't exceed depletion rates it can be somewhat stable in a macabre way.

I'm pretty convinced that the boogeyman is resource nationalism. That's why the USA is transfixed to the point of stupidity over Iraq, Iran, Venezuela and any other exporter with a functioning nationalist government. When you need to extort another 15 million barrels each morning to get you through the day, the job description is clear.

Lately, the desperation is also clear. Rather than blame the political leadership, I blame the public for its shortsighted hypocrisy. There is no law preventing people from voting Green or organizing any sort of political entity they want, or investing in solar power instead of Exxon Mobil. But the history has been to elect them and then blame them as if they were public whipping boys for our sins. We are victims of our own hypocrisy.

Cris , thanks for building that platform to view the problem from.

One thing the view suggest to me is that because of ecological degradation much energy is required, like Alice would say, 'to just stay in the same place'. One could also look on this as an increasing amount of 'friction' in the machine and the resultant loss of 'useful' energy, would you mind commenting on this?.

Chris - the best I can say about this post is that it shows Duncan's Olduvai theory in true light. I prepared a post similar to this one some months back and pulled it becuase I was uncertain of my data.

Chris Clugston, optimistic scenario

I note you favour peak C+C in 2007 (not 2005?) but also quote Skrebowski and Campbell as influencing your work - and both of them see peak in the future - OK they mix in NGL and Syncrude in their numbers.

These are Skrebowski's new capacity figures in his 2007 update:

2007 4.6 Gbs
2008 4.4 Gbs
2009 5.1 Gbs
2010 4.0 Gbs

http://www.odac-info.org/bulletin/documents/MegaProjects_Feb2007.pdf

This is more than enough to compensate for decline of 4.5% per annum in C+C+NGL. The main question is, can you back up your peak oil 2007 position?

I need to join the chorus above pointing out that there will likely be a massive expansion of nuclear - conventional fission, breeders and more complex fuel cycles and eventually fusion.

What's more, as already pointed out the Sun spews out more energy than we will ever be able to consume. With eroei for wind of around 20 and direct solar reported to be around 40, the notion that these will not undergo massive expansion in a fossil solar depleting world is quite simply absurd.

Concentrating Solar Power Guest post by Gerry Wolff posted by Chris Vernon.

Energy from Wind: A Discussion of the EROI Research Guest post by Cutler Cleveland, posted by Nate Hagens.

Finally, I always feel that those who forecast a massive die off shoudl be obliged to present a model for how this will occur. I happen to agree that the world population must stop growing at some point and that decline will likely follow. Famine is my favoured mechanism. What's your's?

Without being able to back it up with numbers, there are qualitative reasons for thinking this is too optimistic a projection. WT's ELM is one (although he can do numbers). Another is Henry's upthread. Yet another is that what I call virtual peak: in global peak, unlike a local peak (e.g. US), there is no place to go, and oil (along with other resources) begin to zoom in value as they sit in the ground -- and the expense of getting them out of the ground zooms -- and therefore there is more and more incentive to get them out of the ground very slowly, if at all.

Beyond that, I think a lot of the 2025 peaks are totally unrealistic. One is looking only at the resource itself, not at the constraints on getting it out of the ground -- the water, the NG, the land, etc. E.g. the tar sands, there's no way production will wait to 2025 to peak.

I saw someone say 2007 (or 8) is the year of peak everything. There might be some truth to that. The peaks do feed into each other in a myriad of ways because of the inter-convertibility of forms of energy (at various prices of course).

It's a good piece, thought provoking. But at least in my case, the title is wrong ...probably sooner than you think.

Good post, very informative, thanks. etc.

Yet:

Overall numbers and ‘averages’ obscure or even deny the tremendous differences between a US SUV driving soccer mom, and a skeletal young woman gathering twigs or brush to burn to heat food - mashed grain of some kind - for her 5, soon to be 6, children. The disparities are so wide, and their impact on world pop so varied that overall analysis like this must be taken only as a rough guide, perhaps even an alarmist measure that does not apply, or is somehow irrelevant, to the ‘rich’, those who have control, military or otherwise. (Which is how many will take it.)

Even if deep recession bites the US ‘white’ parents will be able to feed their children long after the death rate in Africa soars beyond all bounds. The proper figures won’t be published, ethnic strife, local despots - US / west supported -, will be blamed, etc. The rich and powerful will take from the poor, as usual.

For all practical purposes, Global Peak energy is in the past, in the sense that it is anticipated and wars are being fought in function of it. Iraqis were prevented from using their oil (oil for food program, sanctions..) and now are bereft - no proper roads, clinics, water, food, industry, etc. Just one example.

Thanks for the comments on Chris's article.

The article and the comments bring up the question about the use of such models. Paul Saffo describes a good way to think about them in Six Rules for Effective Forecasting (Harvard Business Review):

The goal of forecasting is not to predict the future but to tell you what you need to know to take meaningful action in the present.

I think it's important to make conservative assumptions on a first pass and make those assumptions explicit as Chris has done.

Breeder reactors, fusion, major growth in renewables, electrification of transport, feedback loops -- all of these seem to be in the realm of speculation and advocacy rather than observed long-term trends. They are important factors to discuss, but I don't think they should be assumptions in the base model.

It's important to separate our particular desires and beliefs from observed phenomena, to talk in terms of probabilities and possibilities rather than black/white certainties.

For example, "if transport is electrified, then the model changes in this way..."

Bart
Energy Bulletin

Thanks for a very nice post! While not everyone will agree with your assumptions, your post lays out a neat framework for looking at things. I liked your The End of the Amerikan Dream post also.

If I did my calculations correctly, your conservative scenario implies a 0.4% annual increase in energy to 2025; your optimistic scenario implies a 1.6% annual increase in energy to 2025. If the 1.6% per year increase in energy actually occurs, it is pretty close to what EIA is projecting to 2030 in the International Energy Outlook 2007 (about 1.75% per year). Even a 0.4% annual increase is not that bad. A country with limited population growth could get along quite well on this kind of increase, if total energy were the only constraint, since most forecast some efficiency growth (EIA says 2.2% per year).

There are a lot of ifs in this:

1. Financing has to occur for all of these projects to occur. It is not clear it will with the credit crunch.

2. Energy is not of the "right form". There are likely to be substantial costs in converting transportation to electric or other non-petroleum basis.

3. I expect there will be considerable unevenness among countries. If there is a shortfall of any of the resources, exports of that resource are likely to fall precipitously.

I'm sorry but I consider such high-level projections (mostly) meaningless. Actually I'm inclined to dismiss any predictions post 2030, not to mention 2200.

Yes, it is conceivable to make certain predictions about fossil fuels based on their ultimate availability - they have been relatively well explored for in the last couple of centuries. But to apply similar pattern to their alternatives which are in their infancy... is just stupid. From what we know the limits to alternatives are not geological but technical, economical and even political. There are some speculations about the ultimate availability of uranium for example, but at this stage of uranium exploration this is nothing but a junk science.

It is impossible to model growth rates of nuclear, solar or wind without modeling the technical and economic factors that influence them. In Germany the initial growth of wind was 30-40% per year. Now it is more like 10%. In Denmark the initial rates were also 30-40% and last year it was 0.3%. How much will it be in 20-30 years? Who the hell knows.

Yet another guest poster with invented and out of context figures for ridiculous alarmism.

Exactly why is nuclear or wind expected to decline; One would expect those sources to increase to make up the shortfall from fossil fuels. This whole article is just dumb with a bunch of silly assumptions.

Although the validity of long-range projections can be questioned, I think one point in this article that is obviously true is that there is a tight connection between energy and standard of living. I'm wondering how this relationship will affect the economic growth of China.

China's economy has been growing in the vicinity of 10% per year for some time now, and they seem to have in mind a fast transition to an automobile-based society with a standard of living close to that of the U.S. Obviously, the energy connection makes it clear that they will never get there and never even get close. They may not even be able to continue much beyond where they are already. India is growing fast too, but if there is an energy-imposed ceiling, China will hit it first, and I would think they would do so fairly soon.

But how will this play out? Will China hit the ceiling while other countries with a higher standard of living remain unaffected when they hit it? That seems unlikely. Will China's rise simultaneously drag down the richer nations? It's hard to imagine things playing out smoothly, barring a fantastic increase in some energy source.

80 million BTUs per year is 2.7 kilowatts continuous averaged. I hope that pesky global warming doesn't make people want airconditioning.

Always easier to work in metric.

Probably the most useful contribution by this article is the emphasis on "The “Population versus Living Standard” Tradeoff", a key point often overlooked.

However, I disagree with the concept that

"the maximum supportable human population at any point in time is dependent upon the total amount of energy available to the population at that time",

no matter how many scholars support it. The direct dependence is not on "the total amount of energy" but on "the total amount of food".

Accordingly, the following statement

"Worldwide peak population is determined by dividing the total amount of energy expected to be available during the global peak energy year by the average amount of energy expected to be consumed per capita during that year.

would be correct only if we change "energy" by "food" throughout.

Now, this difference doesn't make my view any more optimistic than the author's. As I have stated in several posts, given that biodiesel from soybean, sunflower and rapeseed is a definite net energy gainer, I foresee an ever increasing diversion of agricultural production into biodiesel production. And I'm not talking only, or even mainly, about US agriculture. Just think of a country that is a big exporter of soybean oil. After a few years of crude oil production decline (2012?) and with an oil price of say $200, is it reasonable to think they would be exporting cheap soybean oil and importing expensive crude? And if the soybean oil price goes up, is it reasonable to think a farmer would plant cheap wheat instead of expensive soybean? That's called arbitraging. Once significant biodiesel production capacity has been built, fuel arbitraging will make the price of diesel fuel (however high it goes) set the floor for the price of vegetable oils. Land arbitraging in turn will set the floor for the price of wheat and corn.

Now, this is where the “Population versus Living Standard” Tradeoff comes into play. Production of biodiesel to meet only food production, processing and distribution needs will leave enough land for producing food for sustaining N billion people living walking and biking lives (not that I don't like that). But if biodiesel-rich countries want to have a higher level of fuel consumption, less food will be produced.

And as I see it, peak food, which is the direct determinant of peak population, will not be between 2025 and 2030. It is now.

I'll throw in my 2 cents, as this is something I've been working up myself over the past few weeks.

I really don't see any point in debating "coulda woulda shoulda" over nuclear energy in either its current or potential forms. That PR battle has been lost, and the entire question is now moot. There is enough opposition to it world-wide to keep development rates down until it's too late to do anything. Likewise, I don't see much point debating energy sources we don't have yet, like fusion.

My position on energy sources is this:

* Oil: The peak is now, we will be effectively out of it by 2080.
* Gas: The peak is in 4 years, we will be effectively out of it by 2070.
* Hydro: Most of the best sites are already developed. We will continue to develop it at a low rate (~1.5% pa) until a plateau in 2040.
* Nuclear: The public relations battle has been lost, the question of developing it is now moot. It will rise to a production peak in 2025, then fall off by 5% pa afterwards.
* Coal: Will rise by 0.5% per year to 2025, then gradually taper off by -0.5% per year after that.
* Wind etc.: Will rise by 10% pa growth for the next 15 years, after which the growth rate will fall off to a plateau in 2050.

I think the shape of the world's energy curve will look about like this:

I put the peak is in 2020, somewhat earlier than Mr. Clugston.

World population will start to decline in 2020-2025, not because of absolute energy shortages, but due to dislocations between now and then brought on either directly or indirectly by oil shortages. The subsequent population decline will be supported by the decline in total energy availability, and will serve to reduce the demand for further development of most sources.

One thing Mr. Clugston's analysis ignores that I think should be addressed is the deteriorated state of the ecosystem, and the effect that will have on carrying capacity as oil and natural gas decline. Oil and gas have been primarily responsible for shielding us from the deleterious effects of depleted soil fertility, fresh water and oceans. As the supply of oil and gas declines, it's reasonable to expect the effect of reduced carrying capacity to become more and more important. Of course rapid climate change, manifesting as increasingly chaotic climatic conditions over the next two decades, will also serve to lower the carrying capacity by interfering with harvests. I've included these factors in my model, and they combine to make the drop in population in my model more severe than in Mr. Clugston's.

Global Thank You from Chris Clugston (author of the article),

Thanks to one and all for taking the time to review my analysis and to offer feedback; you have, both individually and collectively, given me much to think about. I have attempted to address your comments below in a consolidated fashion. (If I missed something, please let me know...)

Immediate Goal

I have posted my avowedly “first pass” analysis to stimulate discussion regarding what I consider to be the most critical challenge confronting humanity—the rapidly approaching peak in total available energy—and to propose an analytical framework for assessing and conveying the associated implications for future human populations, in a manner that can be readily grasped by policy makers and the general public.

Ultimate Goal

In its final form, with conclusions derived from assumptions and projections provided by credible industry experts, the analysis should serve as a tool to build awareness and as a catalyst to instill a sense of urgency on the part of both policy makers and the general public.

The Model

The model itself is quite simple—it is merely an aggregation of assumptions and projections regarding future energy availability by primary energy source. The challenge (and where I obviously need help) is to obtain “the best” possible assumptions and projections from the most credible sources available. Some of you have mentioned energy sources excluded in the current version; fusion etc. If you’ve got specific assumptions and projections, and corresponding sources, please share them. (Thanks to you who already have.)

Information Sources

The assumptions and associated projections in the current model version are admittedly NOT derived from the “best currently available information”; they are based on my interpretation of a limited subset of publicly accessible data and information. If you’ve got more credible assumptions and projections (or know where to get them), and corresponding sources, regarding any primary energy source, please share them. (Thanks to you who already have.)

Time Horizon

If I hit year 2200 projections, plus or minus 50%, I’ll buy you all a beer! The critical point that I think needs to be made—in a quantified way—is that once we reach global peak energy, the total amount of available energy will decline continuously and irreversibly until we reach an “all renewable equilibrium”—and that might take a long time and hit very low levels compared to today’s energy consumption levels. And, coincident with declines in available energy will be declines in human population levels and/or material living standards.

Existing Assumptions and Projections

In a nutshell, energy from each nonrenewable energy source is assumed to increase until peak, peak at some point, then decline thereafter. Energy from each renewable energy source is assumed to increase until peak, peak (or reach a “ceiling of practical deployment”), then either plateau or decline thereafter. Reasons why a renewable energy source could peak (reach a ceiling) and plateau/decline, include:

1. There are only so many places where some renewable energy sources can be effectively deployed and deliver energy when and where needed—and in the form needed: tides, waves, solar, wind, nuclear, and hydro.
2. There are limits to available feedstock or useful life associated with some renewable energy sources: traditional biomass, hydro dams (silt buildup), nuclear plants; actually any physical energy converter, especially those with many moving parts, those that dissipate intense heat, or those that exist in harsh environments.
3. The “subsidizing” energy from fossil fuels and/or the substantial financial investments required to design, produce, deploy, service, and maintain some sources of renewable energy may cease to exist at sufficient levels in the future: nuclear, major hydro—probably most renewable energy sources.

The amount of energy produced by some renewable sources might also increase indefinitely… As is always the case, if you’ve got more credible assumptions and projections, and corresponding sources, regarding any primary energy source, please share them. (Thanks to you who already have.)

Findings/Conclusions

If and when we reach “global peak energy”, the inescapable consequence for humanity will be decreases in population levels and/or material living standards; that much is certain. While the specific decline functions associated with total available energy and human population/living standards cannot be known with certainty, I believe that it is critical to project them both to the best of our abilities, because:

1. Numbers are easy for policy makers and the general public to grasp.
2. Understanding the magnitude of the problem should [might] “motivate” us to plan for the “challenges” that lie ahead.
3. We have not been able to gain much traction with either policy makers or the general public through the utilization of primarily qualitative future assessments.

Thanks again,

Chris Clugston

There must be some validity to the concept of
peak renewables. For example a river system may
not produce any more hydro with extra dams. Denmark is said to be close to peak wind power so there is little point in installing more turbines. Drumbeat links to a review of a new book http://zone5.org/2007/09/09/renewable-energy-cannot-sustain-a-consumer-s...
that discusses this. So far the law of diminishing returns seems to apply to everything; if for example they perfect 'safe' fast breeder reactors I'd expect there must be some quantifiable downside such as huge security costs.

The other problem is the emergy requirement of
additional renewable generation after fossil fuel phaseout. By 2050 can we set aside enough wind power to manufacture more turbines? I'd say we've already seen the best of the consumer age.

As a broad brush stroke, this identifies the problem with the world's carrying capacity with respect to energy-based agriculture and economic activity. However --

Henry wrote:
"Forget the math; when does a system disintegrate as smoothly as it integrated?"

Agree completely. Simply adding up numbers of (possibly) available resources does not take into account the relatively rapid shift in infrastructure and consumption patterns to different energy sources needed to sustain energy-vulnerable economic activities. For example, what happens to all the automobiles produced this year that have an average lifespan of 18 years and cannot run on coal or electricity? Or all of the large suburban homes built in the last 2 decades far from destination centers and reliant on cheap natural gas to heat? As the economy begins to spiral downwards, tax revenues will plummet, and the high cost of maintaining oil-derived asphalt roads, already straining budgets in a booming economy, will rise astronomically.

A fuller treatment of this topic can be found in Joseph Tainter's The Collapse of Complex Societies.

Greetings Again (from the author),

First, let me apologize for my late initial response—this is my first experience with postings and comments, and I failed to fully appreciate the “real time” nature of the process. I’ll do better next time!

Second, several of you have questioned the sources of my energy availability projections. Quite honestly, as Gail pointed out earlier, I used EIA data and projections when and where I could; and IEA information when I couldn’t find global EIA projections—but that only took me to 2030… After that, it’s pretty much all me—a synthesis of information obtained from articles, studies, books, reports, etc. that I’ve read over the past year and a half.

As is readily evident from your commentary, there are those who feel that I am way too conservative and those who feel that I am way to optimistic—which I think is great because it demonstrates the critical requirement for this type of forecasting exercise. If folks such as you, who live and breathe this stuff everyday, are in this much disagreement about the timing and implications associated with global peak energy, how can we possibly present a coherent, well-documented case to oblivious policy makers and a distracted general public?

We may never reach unanimous consensus, especially regarding energy availability in the year 2100 or 2200, but I think that it is important to make long term forecasts based on the “best information currently available”—then to continuously improve our process and results through successive iterations. The preceding analysis is obviously a “first iteration”; it will be interesting to look back on it after several more iterations and laugh about just how “rudimentary” it was!

Finally, I wanted to thank you all again—I’m going to be following up links for weeks!

Best regards,

Chris Clugston

After all the fireworks, I'm still convinced that the article is the start of a very useful way of looking at energy and the future.

However many of the criticisms strike home. I've been thinking about the comments posted here, and have come up with suggestions for Chris that incorporate many of them.

I think these comments apply not just to Chris's model, but to any models of the future.

1. A basic problem is confusion about what the model is. Is it a prediction? Or is it a set of scenarios that can guide us towards intelligent action.

Paul Saffo in his Six Rules for Effective Forecasting (Harvard Business Review) describes the difference between prediction and forecasting (scenarios) as follows:

Prediction is possible only in a world in which events are preordained and no amount of action in the present can influence future outcomes.

...The role of the forecaster in the real world is quite different from that of the mythical seer. Prediction is concerned with future certainty; forecasting looks at how hidden currents in the present signal possible changes in direction for companies, societies, or the world at large. Thus, the primary goal of forecasting is to identify the full range of possibilities, not a limited set of illusory certainties. Whether a specific forecast actually turns out to be accurate is only part of the picture—even a broken clock is right twice a day. Above all, the forecaster’s task is to map uncertainty, for in a world where our actions in the present influence the future, uncertainty is opportunity.

Unlike a prediction, a forecast must have a logic to it. That’s what lifts forecasting out of the dark realm of superstition. The forecaster must be able to articulate and defend that logic. Moreover, the consumer of the forecast must understand enough of the forecast process and logic to make an independent assessment of its quality—and to properly account for the opportunities and risks it presents.

2. A single scenario (or even two closely related ones) gives a false claim of certainty about a complex situation. It tends to restrict our thinking, encouraging a sense of doom and fatality, when instead we need be aware of the choices and what their results might be.

The purpose should be not to get the "right" numbers, but to stimulate intelligent thinking about possible futures.

3. Therefore it would be good to present multiple scenarios for different sets of assumptions.

I think the present two scenarios are a good starting point. Perhaps they should be labeled as "business-as-usual" and "a more optimistic BAU", and representing your view of the most probable futures (if that is what you think they are).

But there should be additional scenarios, showing cases that you think or likely, interesting or instructive. How many scenarios? Maybe 6, maybe 10. Enough to give the flavor of the possibilities, but not so many as to be overwhelming.

Commenters seemed to advocate higher rates of growth for renewables like wind, and for longer periods of growth. Some suggested that that nuclear energy, of various kinds, will play a significant role. I would be interested in a scenarios for extremely aggressive efficiency and conservation measures.

It would be good to see scenarios for possible but hard-to-predict events, such as wars, significant energy discovery, collapse of an environmental system, etc.

Any scenario should have its assumptions clearly spelled out, as well as the reasons for those assumptions. I don't think it's necessary in a report to have detailed tables with all the results, but they should be available at a website.

Bart
Energy Bulletin