Below is a piece by Ted Trainer reviewing a recent report on renewable energy. He argues, contrary to what is often cliamed, that renewables will not proved an affordable source of energy needed to save consumer-capitalist society. The only way to solve global warming (and the other big problems facing humanity) is to take the Simpler Way.
Some critical notes on the Global Energy Assessment’s Renewable Energy chapter.
Ted Trainer
17.12.2012
This massive report (1880 pages and weighing 5.1 kg) contains a 140 page chapter on renewable energy which reinforces the dominant assumption that renewables can provide abundant energy, easily meeting all demand. At the start of the chapter we are told,
“The renewable resource base is sufficient to meet several times the present world energy demand and potentially even 10 to 100 times this demand.” (GEA, 2012, p. 767.)
With 16 lead authors and 11 others contributing to the chapter who could doubt that renewables can save us?
Like the 1000 IPCC page report on renewable (2011), this chapter contains much valuable information, but the discussion does not show that renewable can meet demand, it does not attempt to do this, and it fails to deal with the crucial problems confronting heavy dependence on renewables.
There are now many impressive looking reports claiming to have shown that the world can run on renewables. I have examined several of them in some detail (for addresses see Appendix 1) and do not regard any of them as being at all satisfactory or convincing. All either fail to provide a case, or to deal with the crucial issues, or do not deal with those issues adequately. Many simply state claims or discuss scenarios involving high levels of renewable input, and do not show, via clear assumptions and numerical argument, that the required energy can be provided when and where it will be needed. Like several of these reports, this GEA pronouncement does not even attempt to show this, i.e., it does not include any analysis of the sources and quantities needed to meet demand at particular times or over a year, how problems intermittency and therefore the need for redundant plant would be solved, and what the overall system cost would be.
Minor issues.
Almost all of the chapter simply reports information on various renewable that is available in many reviews, and does not seem to add anything distinctive or new.
No reference is made to any literature doubting the potential of renewable energy, let alone that arguing that it cannot meet global demand.
The above quote is only a statement about the amount of renewable energy out there. The chapter reviews some estimates for the various technologies, e.g., the amount of solar energy falling on the land, the total amount of wind energy. This kind of exercise is engaged in by other renewable optimistic analyses but it is more or less pointless, as well as highly misleading. It is obvious for instance that there is a vast amount of energy in the sunlight falling on the earth, but that tells us nothing about how much of it can be a) harvested and b) delivered c) reliably, at d) an acceptable price.
This is the general issue of the difference between a technology’s “theoretical potential” and what it can deliver in the real world after all economic, ecological, social, political, cultural and other limiting factors have been taken into account. The theoretical potential quantity of the global biomass harvest has been estimated at over 1500 EJ/y. (Smeets and Faaij, 2008.) That is in fact around the total biomass growth each year on the planet. However how much of this could be provided as useable energy at an acceptable cost, without depleting biodiversity, without depriving native and peasant people of their vital resources, at an acceptable energy return, without taking resources needed for timber, fuel and fibre, and while providing for the replanting needed to restore the planet’s seriously degraded ecosystems? The answer given by Field, Lobell and Campbell (2007) is 27 EJ/y, around 2% of that theoretical potential figure.
The integration problem
The crucial problem for renewable energy supply is set by the highly intermittent nature of almost all renewable sources. A plot for the contribution of a national wind system over time typically shows an extremely jagged pattern, often descending to 3% or less even in Denmark, and at times a negative output, e.g., in Victoria ( because the system sometimes has to draw energy from the grid to maintain the generators.) What matters most is how such erratic inputs can be combined to meet demand. Following is the summary statement from GEA on their response to this integration problem.
System integration studies show no intrinsic ceiling to the share of renewables in local, regional, or global energy supplies, depending on the resource base and energy demand. Intelligent control systems, supported by appropriate
energy storage systems and energy transport infrastructure, will help renewable energy meet the energy demands of different sectors. However, the variability of wind, solar, and several ocean energy resources can create technical or cost barriers to their integration with the power grid at high levels of penetration (20% or above).To reduce or overcome these barriers, the main approaches in the electricity sector involve: drawing power from
geographically larger areas to better balance electricity demands and supplies; improving network infrastructures; increasing the transmission capacity, including the creation of so-called supergrids for long-distance power transmission; developing the Smart Grid further; applying enhanced techniques to forecast intermittent energy supplies hours and days ahead with high accuracy; increasing the flexibility of conventional generation units
(including dispatchable renewables) to respond to load changes; using demand-side measures to shift loads; curtailing instantaneous renewable supplies when necessary to guarantee the reliability of power supplies; and further developing and implementing energy storage techniques.(p. 769. This is the end of discussion of this topic.)
This is a common form of “argument” in the renewable arena. A problem issue is identified, followed by reference to the kinds of technologies and strategies that can be applied to it...with no attempt to show that they can solve the problem. The quoted list is of ways that can make a difference, but the question is whether they can make a big enough difference. This would require a detailed numerical case deriving/demonstrating the conclusion from plausible assumptions. The more detailed discussion later in the chapter, occupying 10 pages, does not even attempt to do this. It merely provides superficial accounts of some options, e.g., half a page on the vehicle to grid strategy, and the closest it comes to a relevant conclusion on integration is to state that penetrations of 30% - 35% are feasible... Earlier reference is made to studies claiming that it could be up to 95%.
Following is an indication of the magnitude and difficulty of the integration problem, which this report goes nowhere near representing. (These points have been made several times in the previous critical reports I have circulated, listed below.)
Firstly it is important to point out that there is no difficulty in explaining how 100% of demand can be met by renewable sources – the difficulty is in explaining how that could be afforded. In other words to do it would require a great deal of redundant back up plant to be resorted to when there is insufficient wind or solar etc. energy available, and the numerical analyses I have explored indicate that this amount would involve impossibly high capital costs.
The nature of the problem is evident in this report’s Fig. 11.74 (p. 866) which shows that in the system considered where average annual demand is 3,300 MW the amount of PV, wind, hydro and biomass electricity generating plant needed would be 5,330 MW, and another 1750 would have to be imported from outside the system. In one month the PV component, capable of providing 1000 MW, would be providing only 100 MW. Thus the amount of plant required to meet average demand would be over twice as much as would be needed in the form of coal or nuclear power plants.
However this common approach, taking monthly or annual average demand and contributions, is not appropriate and is highly misleading. It suggests that far less redundant plant is needed than is actually the case. What happens when there is no wind or sun anywhere in your continent for two weeks? How many solar panels or turbines, or solar thermal plants in North Africa do you need then, standing by to resort to in these situations? This is the problem of the Big Gap weather event. Following is an indication of the magnitude and frequency of occurrence of such events.
Oswald, Raine and Ashraf-Ball, (2008) show that for the first 6 days of February 2006 there was almost no wind energy generated from Ireland to Germany, and one of these days was the coldest of the year in the UK. Although not reported, it would probably also have been a period of negligible solar energy. The situation was not much better over a 14 day period. Similar documentation is given by Soder et al., (2007), Sharman (2005) and Sharman, Leyland and Livemore, (2012) for West Denmark, Flocard and Bach for several European nations, Mackay (2008), for the UK, E On Netz (2004) for Germany, Davey and Coppin, (2003) and Lawson (2012) for Australia, and by Lenzen’s review, (2009.)
An indication of the magnitude and seriousness of the this intermittency and redundancy problem can be given by reference to two recent analyses put forward by groups who claim that 100% renewable supply is achievable. The study by Elliston, Diesendorf and MacGill (2012) claims to show how 100% of Australian electricity demand could be met by combining varying inputs from renewable. The study is valuable in exploring the way renewable sources might be combined from hour to hour in an effort to meet demand, as for instance PV fades out in the evening and hydroelectric supply can be phased up. The study concludes that in order to meet an average 25 GW demand the amount of renewable capacity required would be 84 GW, 3.3 times as much coal, gas or nuclear capacity as would suffice.
The second illustration is the modelling study by Hart and Jacobson, (2011) claiming to show that almost all of Californian delivered energy could be produced from renewable sources. However Table 2 on p. 2283 reveals that to meet a 66 GW demand with low carbon emissions no less than 281 GW of capacity would be needed. This would include 75 GW of gas generating capacity which would be required to plug gaps in renewable availability. It would function a mere 2.6% of the time (p. 2283) and it will provide only 5% of annual demand. This means 75 power stations would sit idle almost all the time.
Neither of these two analyses show that big gap events have been adequately provided for. Elliston, Diesendorf and MacGill include a diagram indicating how renewable sources could be combined to meet demand through several days, but all of these days have considerable wind and solar energy input. An accompanying slide report refers to gaps of four to nine days in solar radiation at the best Australian solar thermal sites.
Any claim for high penetration renewable supply wishing to be taken seriously must base its provision on detailed long run information on wind and solar energy conditions, making clear the frequency and magnitude of big gap (and lesser) events. It needs to show how much redundant back up plant would have to be built to enable supply to be maintained through these periods.
It is necessary here to counter the common retort, “ … but the wind is always blowing somewhere.” If the wind is blowing strongly today in region A and the total wind sector contribution is to be supplied by that region today, then it will have to contain enough wind generating plant to meet that contribution. If tomorrow the wind is only blowing well in region B then that region will also have to contain enough generating capacity to meet the whole wind contribution. Thus in every region which might be the only one where the wind is strong on a particular day we would need sufficient capacity to meet the whole wind quota. In other words, to be able to always meet the wind quota would require several times the amount of plant needed to make wind’s average annual contribution, and most of it would be idle much of the time. Also, for much of the time the whole system would be producing far more than could be used.
The redundancy problem can be reduced to the extent that energy storage is possible. This chapter gives about one and a half pages to the topic and again proceeds as if it is sufficient to point to storage technologies that exist or can be developed, without attempting to show that they can be provided on the scale needed to solve the intermittency and redundancy problem.
The liquid fuel problem.
Electricity makes up only about 20-25% of energy use in rich countries, and 13% of global energy use. Almost all renewable sources provide only electricity. This sets the question, from what renewable sources is the other 87% of energy going to come. Biomass is not capable of being the answer.
This chapter estimates global primary biomass availability at 160 - 270 EJ/y, (p. 772) which is around half the IPCC estimate. In my view even this is highly challengeable given the reasons why we should minimise use of this source. These include
- Increased pressure on land for biological materials will increase Rising energy costs will tend to move structural materials from steel, aluminium and cement to timber.
- Water is a problem for very large scale biomass production, especially in view of the climate problem.
· Large quantities of carbon would be removed from soils and ecosystems. Patzek (2007) argues that over the long term carbon should not be removed and if it is soils inevitably deteriorate. In the coming era of probably severely limited availability of petroleum and fertilizers it is likely that agriculture will have to focus more intensively on the organic factors contributing to yields, t maximum retention of soil carbon and therefore maximum recycling of crop “wastes” is likely to become crucial.
- The biodiversity effects are probably the most disturbing. There is an urgent need to return vast areas to natural habitat, rather than contemplate taking more from nature. In addition biomass plantations focus on a few high yield species, meaning that large areas would not have natural levels of biodiversity.
- More than 40% of the biomass potential the IPCC estimates is urban, industrial and agricultural “waste”. It is likely that in future this category will be significantly reduced as resource scarcity, reduced affluence and greater conservation and recycling effort reduces biomass waste streams.
· Biomass energy conclusions depend greatly on the assumed biomass growth yield. It would seem that the common biomass energy yield per ha assumption of c. 13 t/ha/y, (evident in the IPCC discussion) is unrealistic as an average for very large scale production. World average forest growth is only 2 - 3 t/ha/y. A more realistic biomass-energy yield figure might be 7 t/ha/y.
- According to the IPCC (2011) 80% of the present 50 EJ/y harvest of biomass energy is “traditional use” by tribal and peasant people. This is labelled “inefficient” use and the report anticipates shifting this land to the much more “productive” use characteristic of modern biomass energy systems. In view of the low yield/efficiency, that area is likely to correspond to 750 million ha. However this land provides crucial services sustaining the lives and livelihoods communities of the poorest billions of people on earth, the building and craft materials, food, medicines, hunting, animal fodder, water and products to sell. The greatest onslaught of the global economy on the poorest billion is the taking of the land on which they depend. To move this land into modern “efficient” production would inevitably be to transfer the resource from the poor to the rich.
For these reasons it is probable that only a relatively small amount of land should be put into global biomass energy production. However if we take the 200+ EJ/y figure this chapter arrives at, it would probably produce less than a net 100 EJ/y of ethanol or methanol. If renewables were to meet total electrical demand, presently in the region of 65 EJ/y, adding all this biomass would explain where only half the present world energy consumption could come from.
All of this has to be considered not in terms of present global energy demand but in terms of where it is heading. The general pre-GFC expectation was that it is heading to a possible doubling by 2050, or maybe somewhat less.
That would enable a global per capita average supply of 110 GJ/person, around only one-third of the present Australian use (assuming population reaches 9 billion.). Those who believe renewables can meet demand therefore need to explain how up to six times present global consumption can be supplied.
The capital cost issue
This report does not consider the capital cost of a global 100% renewable energy supply system.
Trainer 2012a offers a clear and followable numerical case deriving from explicit assumptions the conclusion that to meet probable global 2050 demand from renewable sources would require an unaffordable quantity of redundant plant.
Note that it is increasingly accepted that by 2050 all greenhouse gas emissions must have been eliminated if serious climate danger is to be avoided. (Meinshausen et al., 2008, Hansen, 2008) so it will not be good enough to meet only a high proportion of demand from renewables.
The foregoing has not been an argument against transition to renewable energy. It is an argument against the possibility of running a energy-intensive affluent consumer-capitalist society on them.
Conclusion
The GEA renewable chapter is of little value. Its summary of technical evidence is useful but does not seem to add much to other reviews. The report provides no case in support of any conclusion that renewable can meet future global energy demand. It is not that its case is inadequate; the 140 pages do not present a case. At best they present information on gee-whiz technologies which might lead some to think that the potential in the renewable field will be able to do it.
The main significance of the chapter is that it will be taken as another impressive documentation reinforcing the dominant faith that renewable energy alternatives exist in abundance and all we need to do is shift to them, and then our energy and climate problems can be solved, and we can all go on enjoying affluence and growth forever. In the view of an increasing number it is precisely this mindset that is condemning the planet to catastrophic breakdown and the probable die off of billions. (Smith and Pisano, 2012, for instance argue that such outcomes now cannot be avoided.)
Energy is only one item in the list of problems involved in the accelerating multidimensional and terminal crisis. We are rapidly depleting biological, mineral, agricultural social and cultural resources, four billion suffer serious deprivation and over 1 billion are chronically hungry, and ecosystems are deteriorating alarmingly. The fundamental cause is simply a global level of production and consumption that is grossly unsustainable. The Australian “footprint” of productive land required to provide the “living standard” each individual enjoys takes around 8 ha of productive land. Making the unlikely assumption that by 2050 there will be as much productive land as there is now, the global per capita average available will be one-tenth of the amount Australians use now. This makes clear the magnitude of the over shoot. The problems cannot be solved unless there is an enormous reduction in rich world and in global levels of production, consumption, business turnover, trade, investment and GDP.
Yet the supreme goal within all nations is to raise these levels constantly and without limit; i.e., it is economic growth. If by 2050 all expected billion had risen to the “living standards” we in Australia would then have given 3% p.a. economic growth, world economic output would be at least 20 times as great as it is now. The absurd and suicidal nature of this mindless obsession is glaringly obvious, but it is almost entirely ignored.
Trainer (2010) details this case, showing that a sustainable and just world cannot be conceived other than in terms of a transition to some kind of Simpler Way. Its core characteristics must be mostly small and highly self-sufficient and self-governing communities, within an economy not driven by market forces and profit and with no growth, and priority given to frugality, community, cooperation and giving rather than getting...and 100% dependence on renewable energy. The book argues at length that in such a society the quality of life would be much higher than it is for most people now, with no reduction in socially-useful R and D or high tech. (See TSW website, Trainer 2011.)
The prospects for such a transition are negligible. This is partly due to the unjustifiably optimistic pronouncements of renewable energy advocates which reinforce the faith that renewable can solve our problems and the commitment to affluence and growth need not be questioned.
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