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Renewable Energy Cannot Sustain a Consumer Society
by Ted Trainer
In the last three decades considerable concern has emerged regarding limits to the future availability of energy in the quantities required by industrial-affluent societies. More recently Colin Campbell and others have argued that the energy source on which industrial societies are most dependent, petroleum, is more scarce than had previously been thought, and that supply will probably peak between 2005 and 2015. Some of these people argue that the world discovery rate is currently about 25% of the world use rate, and that non-conventional sources such as tar sands and shale oil will not make a significant difference to the situation. The USGS (2000) has recently arrived at a much higher estimate for ultimately recoverable petroleum, but this would only delay the peak by some 10 years.
If the discussion is expanded to take into account the energy likely to be required by the Third World, the situation becomes much more problematic. If the present world population were to consume energy at the rich-world per capita rate, world supply would have to be five times its present volume. World population is likely to reach 9.4 billion by 2070. If all these people were to consume fossil fuels at present rich-world per capita consumption rates, all probably recoverable conventional oil, gas, shale oil, uranium (through burner reactors), and coal (2000 billion tonnes assumed as potentially recoverable), would be totally exhausted in about 20 years.
In effect we have to give up fossil fuels altogether.
What is not well understood is the magnitude of the overshoot, the extent to which our present consumer society has exceeded sustainable levels of resource use and environmental impact. This is made clear by a glance at the greenhouse problem. The Intergovernmental Panel on Climate Change has given a range of emission rates and the associated levels that the carbon dioxide concentration in the atmosphere would rise to.
Perhaps the most quoted graph shows that if the concentration is to be stabilized at 550 ppm, twice the pre-industrial level, emissions must be cut to 2.5 gigatonnes per year (Gt/y) by 2040 and to 0.2 Gt/y by about 2200. The present level from fossil fuel burning (i.e., not including land clearing) is over 6 GT/y.
To keep the concentration below 450 ppm, emissions must be cut to about 1 + Gt/y by 2100, and to about 0.3 Gt/y by 2200. This target is much too high because the atmospheric concentration is now at about 380 ppm and many disturbing climatic effects are becoming apparent.
If world population reaches 9+ billion, a global carbon use budget of one Gt would provide us all with about 150 kg of fossil fuel per year, which is around 2–3% of our present rich-world per capita use of fossil fuels (in GHGe terms). Alternatively only about 170 million people, 2.5% of the world’s present population, could live on the present rich-world per capita fossil fuel use of over 6 tonnes of fossil fuel per year.
These figures define the enormous magnitude of the sustainability problem we confront. Consumer-capitalist society has overshot viable levels of production and consumption by a huge amount. In effect we have to give up fossil fuels altogether. That is, we have to live almost entirely on renewables. This book argues that these very high levels of production and consumption and therefore of energy use that we have in today’s consumer-capitalist society cannot be sustained by renewable sources of energy.
However, the foregoing numbers only define the magnitude of the present problem. This is nothing like the magnitude of the problem set when our commitment to growth is also taken into account. If 9.4 billion people are to have the “living standards” we in rich countries will have by 2070 given 3% economic growth, total world economic output every year would then be 60 times as great as it is now.
The question of whether we can run our society on renewable energy is therefore not about whether it can meet present demand, and this book concludes that it cannot do that, it is about whether it can meet the vastly increased demand that will be set by the pursuit of limitless increase in production and consumption.
There is an overwhelmingly powerful, never questioned, assumption that all these problems can and will be solved by moving to renewable energy sources. That is, it is generally believed that sources such as the sun and the wind can replace fossil fuels, providing the quantities of energy that consumer society will need, in the forms and at the times that they are needed. Surprisingly, almost no literature has explored whether this is possible. Unfortunately in the task of assessing the validity of this dominant assumption we have not been helped by the people who know most about the field, the renewable energy experts. They have a strong interest in boosting the potential of their pet technology and in not drawing attention to its weaknesses, difficulties and limits. Exaggerated, misleading, questionable and demonstrably false claims are often encountered in the promotional literature. Minor technical advances which might or might not become significant in the long run are announced as miraculous solutions. Doubts regarding the potential of renewable technologies are rarely if ever heard from within these fields.
…renewable energy experts…have a strong interest in boosting the potential of their pet technology…
This enthusiasm is understandable in view of’ the need to attract public support and research funding, but it means that contributions by those most familiar with these fields to the critical assessment of the potential and limits of renewables are quite rare. In developing the following review, considerable difficulty has been encountered from people hostile to having attention drawn to the weaknesses in their technologies and proposals (including threats of legal action if data they have provided in personal communications is used). Sources eager to provide information tend to dry up when they realize that limits are being explored. In addition some of the crucial information will not be made public by the private firms developing the new systems. For example it is almost impossible to get information on actual windmill output in relation to mean wind speeds at generating sites.
Unfortunately these difficulties have meant that at times it has not been possible to get access to information that would settle an issue and that must exist somewhere, and that at times one has to attempt an indirect estimation using whatever scraps of information one has been able to find. Ideally this study would have been carried out by someone more expert in renewable energy technology than I am, but it is understandable that the task has been left for an outsider to take up.
The two core problems
Renewable energy can meet various needs very well, or perfectly in many regions, such as heating and cooling space via simple “solar passive” designs whereby the structure captures and stores solar energy. However, renewables face formidable problems with respect to the two forms of energy which consumer society demands in enormous quantities, viz. electricity and liquid fuels. The fundamental issue in both cases has to do with the quantity of energy that can be delivered reliably, not dollar cost or “energy return.”
The situation is clearest with respect to liquid fuel (i.e., oil plus gas). There is no possibility of getting the quantity we take for granted, no matter what plausible assumptions are made regarding technical advances. There are only two possible sources of renewable liquid fuels, biomass and hydrogen. Even wild optimism about potential land and energy yields cannot provide the world’s future 9.4 billion people with more than perhaps 10% of’ the per capita liquid fuel consumption we now average in rich countries.
The situation concerning electricity is less clear cut. Some regions such as northeast Europe and the US will be able to derive a lot of electricity from the wind in winter (although the situation in summer is much more problematic). Yet even if the quantity of wind and solar electricity was not a problem, very difficult problems remain having to do with making these highly variable forms of energy available at the times when they are needed.
It is quite misleading to focus on the contribution a renewable source can make when it is merely augmenting supply largely derived from coal or nuclear sources. In that situation the significant problems set by the variability of renewables can be avoided. When the sun is not shining or the wind is not blowing, a little more coal can be burned. However, the problem this book is concerned with is the development of systems in which almost all energy used comes from renewables, and that means we would have to provide for large fluctuations in energy production, and thus for the storage of large quantities of energy. At this point in time there is no satisfactory solution in sight for this problem, on the scale that would be required.
Electricity is more or less impossible to store in very large quantities…
Electricity is more or less impossible to store in very large quantities, so it has to be transformed into something that can be stored, such as hydrogen or pumped water, then transformed back to electricity when it is needed. However, these processes involve significant difficulties and costs. The best option, using electricity to pump water into high dams and then using its power to generate electricity when there is insufficient wind, involves the problem of limited hydro-capacity. Less than 10% of world electricity is generated by hydroelectric generating power, so this source cannot carry anywhere near the full load when there is little wind or sun.
In other words the biggest difficulties for solar and wind energy are set by their variability, especially the occurrence of night time and winter for solar, and the fact that winds can be down for days at a time. Many sites with quite satisfactory summer PV or solar thermal performance are almost useless right through winter, especially in Europe. Winds tend to be low in summer and autumn. Even more problematic for wind are the large variations from day to day as gales and calms occur.
At present it seems that the variability of wind means that it probably cannot provide more than 25% of demand in the best wind regions, and perhaps no more than 10 to 15% in most good wind regions. Variability also seems to mean that if we build a lot of windmills we might also have to build almost as much coal or nuclear generating capacity to use when the winds are down.
…the variability of wind means that it probably cannot provide more than 25% of demand in the best wind regions…
The belief that the world will soon run on a “hydrogen economy” is very common. The first challenge to this faith-based assumption is the question of a source for the huge quantities of hydrogen that will he required. We are not likely to get enough energy from solar or wind sources to meet electricity demand, let alone have any left over to convert into hydrogen. But even if we had a lot of hydrogen, there are coercive arguments as to why we still could not have a hydrogen economy These involve the difficulties posed by the physical nature of the very small and light hydrogen atom. Large volumes of hydrogen have to be pumped or stored before much energy arrives at the destination, and this consumes a lot of energy. In fact according to one estimate, pumping hydrogen from the Sahara to northern Europe would use up the equivalent of 65% of the energy pumped. Then there would be other losses and energy costs in moving the hydrogen into fuel tanks, and especially driving motors and generating electricity. Finally fuel cells are likely to deliver at most 50 to 60% of the energy that reaches them as hydrogen after all those pumping losses.
If the losses are combined, we find that to provide electricity or run vehicles from wind power via hydrogen would require 3 or 4 times as much wind-generated energy as there is in the petrol we are trying to replace. Similar losses would be involved in storing wind-generated power in hydrogen and using it to regenerate electricity later. The capital cost of such a generating system could be 12 to 15 times as much as that of the coal-fired generating system, not including the cost of the hydrogen production, pumping, storage and fuel cell systems.
This poses the question of what multiple of present electricity cost could be tolerated. Our economy might survive if electricity cost five times as much as it does now, but could it survive a 10-fold increase?
What about using solar energy in summer and autumn when the winds tend to be low, and wind in the winter when there’s little sun? This would mean constructing two very expensive systems in addition to the one we have now. We would have the wind system, the solar system and the coal-fired system for use when the other two are not working.
An unsustainable and unjust society
For forty years the argument has been accumulating that our resource consuming and environmentally expensive way of life is grossly unsustainable, for many reasons besides energy difficulties. The rich-world per capita “footprint” is about ten times that which could ever be extended to all people. In addition our way of life is built on a grotesquely unjust global economy. We in rich countries could not have such high “living standards” if we were not taking most of the world’s resource wealth and condemning the Third World to a form of “development” which benefits us and our corporations but not the mass of Third World people.
Most people assume that although some of our resource and ecological problems are very serious, they can be solved by strategies like greater recycling efforts and the development of better technology. This “tech-fix” position is quite mistaken because the overshoot is already far too big for this to be possible. Reductions possibly of the order of 90% are required in rich-world per capita resource use.
All our problems will rapidly become worse if we continue to be obsessed with constantly increasing production and consumption, living standards and the GDP. Yet these are the fierce and supreme commitments of just about all governments, economists and people, and we have an economic system that cannot work without them.
A global consumer-capitalist society cannot be made sustainable or just. We cannot solve the big global problems such a society generates unless we face up to transition to a very different kind of society. Salvation cannot be achieved by changes within consumer-capitalist society — there must be change from it to very different social, economic, geographical, political and cultural systems.
The rich-world per capita “footprint” is about ten times that which could ever be extended to all people.
It should be stressed that this book is not an argument against the development of renewable energy sources. For some forty years I have argued that renewable energy sources are ideal, that we must move to them, and that we can live very well on them — but not at the level of energy use we take for granted today in consumer-capitalist society. Far from being hostile to them, I have always relied on renewable energy forms. Our homestead has a wood fire for space heating, for decades our cooking was by wood stove (not at present), we pump our water by windmills, and for thirty years have had PV panels on the roof and no grid connection. In several previous publications I have argued that in a sustainable world we must live on renewables and that we can live well on them, but only after radical transition from consumer-capitalist society to “The Simpler Way.”
Apologies to “Green” people
Obviously this book’s message is not a pleasant one for people in the Green Movement and I am acutely aware of the damage it would do the general environmental cause if it were taken seriously. Environmental activists have great difficulty getting the public in general to respond to environmental issues, even when they pose no significant challenges to the lifestyles and systems of consumer society.
Almost all environmental activists seem to be oblivious to the contradiction built into their thinking. They are in effect saying, “Please help us save the planet by calling for a switch to the use of renewable energy sources — which can sustain consumer society and will pose no threat to our obsession with affluent lifestyles and economic growth.” Even getting people to attend to such unthreatening messages is very difficult. So how much more difficult would it be to get people to listen to the claim that to save the environment we have to cut consumption by perhaps 90%, and give up fossil fuels — and renewables cannot substitute for them?
Almost all environmental activists seem to be oblivious to the contradiction built into their thinking.
Given that I have been part of the Green Movement for decades, I realize that green goals could be significantly undermined if the theme of this book became widely discussed, let alone generally accepted. The most immediate effect would be a surge in support for nuclear energy.
The Green Movement in general is deeply flawed. It is for the most part only light green. Most environmental gurus and agencies never go beyond seeking reforms within consumer-capitalist society.
A sustainable and just society cannot be a consumer society, it cannot be driven by market forces, it must have relatively little international trade and no economic growth at all. It must be made up mostly of small local economies, and its driving values cannot be competition and acquisitiveness. Whether or not we are likely to achieve such a transition is not crucial here (and I am quite pessimistic about achieving it). The point is that when our “limits to growth” situation is understood, a sustainable and just society cannot be conceived in any other terms. Discussion of these themes is of the utmost importance, but few if any green agencies ever even mention them.
The “tech-fix optimists” who are to be found in plague proportions in the renewable energy field are open to the same criticism. If the position underlying this book is valid, then despite the indisputably desirable technologies all these people are developing, they are working for the devil. If it is the case that a sustainable and just world cannot be achieved without transition from consumer society to a Simpler Way of some kind, then this transition is being thwarted by those who reinforce the faith that technical advances will eliminate any need to even think about such a transition.
The Simpler Way could easily have an extremely low per capita rate of energy consumption, and footprint, based on local resources — but only if we undertake vast and radical change in economic, political, geographical and cultural systems
Ted Trainer teaches at the University of New South Wales in Kensington, NSW, Australia.
[17 dec 08]