Summary: The report's two crucial conclusions are that the greenhouse problem can be solved by adoption of alternative technologies, and that this can be done at negligible cost to GDP.
The glaring fault in the Report is its failure to discuss the energy assumptions underlying these conclusions, which I argue are invalid.
The core assumption is that alternative energy technologies can be scaled up by the huge magnitudes required to replace fossil fuels.
There has been almost no study of this issue, i.e., the limits to renewable energy sources. The paper looks at the quantities of wind, solar, geo-sequestration etc. that would have to be provided if Garnaut's conclusions were to be achievable, and indicates why these quantities are impossibly large.
If these arguments are valid then it will not be possible to provide the amount of energy consumer capitalist society demands while achieving acceptable greenhouse targets. lt is argued that the greenhouse and energy problems must be seen as elements within the general limits to growth predicament, and that these and other alarming global problems cannot be solved without transition to some kind of Simpler Way.
The 12 page paper is dated 13-11-08 and can also be found at Critical feedback on the paper would be welcome.
The Final Garnaut Report; A Radical Critique of its Energy Assumptions.
The publication of the Final Garnaut report (2008) has made a significant contribution to increasing awareness of the magnitude and urgency of the greenhouse problem and it has moved Australia towards the implementation of carbon trading. However the lengthy and detailed report is based on crucial energy assumptions that are not discussed let alone established. The argument below is that these assumptions are invalid and therefore Garnaut’s conclusions are unsound and his policy recommendations are seriously misleading.
Like the Stern (2007) and IPCC Fourth Report Working Group 3 (2007) analyses of carbon mitigation Garnaut’s core conclusion is that the greenhouse problem can be solved by the adoption of alternative technologies at negligible cost to GDP. In other words, these three highly influential reports reaffirm the common belief that conservation effort, geo-sequestration, nuclear energy and renewable energy sources can cut greenhouse emissions to safe levels while GDP continues to grow at more or less historical rates. Remarkably, none of these reports considers the reasons for concluding that the alternatives cannot replace fossil fuels, at any economic cost. This case is detailed in my Renewale Energy Cannot Sustain Consumer Society, (Trainer, 2007a), and a more recent summary of the case is given in Trainer 2008. (Critiques of the Stern and IPCC Reports are given in Trainer 2007b, and Trainer 2007c.)
Garnaut’s treatment of the crucial assumption
Garnaut concludes that the desirable target for atmospheric CO2 concentration is 450 ppm (although he recommends a 550 ppm target on the grounds that the lower one is not likely to be accepted.) The IPCC estimates that the 450 ppm target would result in a 2 – 2.4 degree rise in temperature. Many would now say that this runs an unacceptable risk of global ecological damage. Hansen (2008) argues that the appropriate target is in the region of 380 ppm, which the world has already passed.
Garnaut aligns with the IPCC in saying that the target would require all carbon emissions to be eliminated by 2100. He anticipates that by 2100 Australian electricity consumption is likely to be 7 times as great as it is now, i.e., around 5.25 EJ/y. (Fig. 20.10.) His Fig. 20.18 anticipates that globally electricity will be generated at a rate that is 10.3 times the present rate, i.e., 103 TWh/y or 620 EJ/y. These figures represent huge increases on present electricity consumption rates, and Garnaut is saying they will be achieved without carbon emissions (p. 482) or significant economic cost. Apart from a few superficial remarks, no explanation, derivation or defence of these assumptions or conclusions is given in the 700 page Report. Almost no reference is made to the possible magnitudes of the contributions that might be made by renewable energy sources, geosequestration and nuclear energy. He simply assumes or states that alternative technologies will be able to cut emissions sufficiently. Almost all of the relevant statements in the 700 page report are given in the brief Appendix 1 to this paper.
The energy targets.
First, note again the magnitude of the problem. By Garnaut’s own account the 2100 global target is a 10 fold multiple of present electricity supply, and a 7.5 multiple for Australia, with 95% of it coming from non-carbon emitting energy sources.
It is not clear how Garnaut accounts Australia’s probable transport energy and the figures do not seem to add up. Fig. 21.4 shows transport emissions rising from 80 million t/y to 350 million t/y under business as usual, but falling to about 20 million t/y by 2100 under the Standard run. (p. 512.) It is assumed that by the end of the century zero-emissions fuels account for 90 per cent of fuel use in these transport modes. (p.. 513.) This would mean that transport energy demand would multiply by 4.375, to 4.725 EJ.
However Fig. 20.10 shows total electricity demand is expected to be 5.25 EJ by 2100, which would mean only .875 EJ would be left to meet direct electricity demand, which is already .7 EJ and increasing at around 3% p.a. If direct electricity demand increases only at the rate ABARE expects Australian energy demand to settle to to (1.9% p. by 2030), then by 2100 it will be 6 times as great as it is now, around 4.2 EJ/y. If we add to this the electricity Garnaut assumes for transport the total is 9.45 EJ, 13.5 times the present amount, not the 5.25 EJ Garnaut’s Fig. 20.10 indicates.
The faulty methodology; "Top down" modeling.
Like Stern and the IPCC Working Group 3 and virtually all analyses of carbon mitigation, Garnaut has relied solely on either "bottom up" modeling (costing each unit of replacement technology and multiplying by the amount that would be needed) or top down modeling (estimating the effect that overall measures such as a carbon tax would have on a choice of energy sources). Garnaut’s approach is in general "top down" although he says some of the studies referred to were "bottom up".
The logic of the former approach asks what amount of tax on carbon would raise the cost of carbon based energy to the point where users would turn to other sources. To answer this question satisfactorily we would need to know firstly what the other sources cost, and more importantly whether they can be implemented on the scale required. This second question is not asked by Stern, the IPCC, or Garnaut. The following section sketches some of the many reasons for concluding that the alternatives cannot be scaled up sufficiently.
The reasons why alternatives cannot replace carbon fuels.
Let us take the global electricity target Garnaut assumes, 620 EJ/y, and also assume one-third of this comes from geosequestration, wind and solar sources respectively.
If one-third of 620 EJ, i.e., 206 EJ was to come from coal via geosequestration which captured 90% of emissions (and it might be only 80%), this would be about 6 times the present amount of world electricity produced from coal. If 90% of emissions were captured, emissions from electricity generation alone would be about 1/2 of the present global total CO2 emission level, when the target must be zero. In addition at that rate of coal use the commonly estimated probably recoverable coal resource of 1 trillion tones would last less than 40 years. (However the Energy Watch Group, 2007 (see also Hienberg, 2007), believe resources are much more limited than has been generally assumed, and that coal supply could peak within about 2 decades.
Note that all this is only for the provision of electricity and other forms of energy would also need to be explained. At present 40% of Australian energy is not accounted for by electricity plus transport.
If 206 EJ of electricity was to come from wind, where would this amount of capacity be located? Garnaut notes that there could be a problem of "site availability" (p. 481.) Trieb (undated), a strong advocate of renewables, estimates that total on and off shsore European potential is only 4 EJ. Europe would have to draw from a far wider area such as Czisch (2004) advocates extending from Morocco to Khazakhstan. This would set problems to do with transmission loss and equity; i.e., the right of other people in those areas to a share of the wind energy they produce.
If Australia is to use 7 times its present .7 EJ/y of electricity, and one-third of this is to come from wind, then wind supply would be 1.7 EJ/y. This is 50 times the amount of wind energy that the Sustainable Energy Development Authority estimated in 2005 might be provided by wind farms in NSW. Australia would need about 156,000 windmills of 1.5 MW capacity (at global average capacity of .23; IPCC, although Australia is likely to exceed this.) Average annual mill production for replacement purposes would have to be about 6,000, costing perhaps $9 billion p.a., not including transmission line replacement.
If we assume that Australia has 5000 km of coast with ideal wind conditions, then at normal spacing (5 x 10 diametres) the mills would form a band 156 km wide. (This is a significant underestimate, given the fact that areas are excluded by prior use, and that wider spacing would be required in a continuous band.)
To derive one-third of a world 620 EJ electricity supply from PV sources, at average Sydney insolation, yielding about .85 GJ/m/y, would require 242 billion square metres of panels, which would probably be 27 metres per person (for 2050 population). For most of the world insolation would be much lower than in Sydney.
If Australia was to derive 1.7 EJ p.a. from solar panels we would need 2 billion square metres of panels, possibly 66 square metres per person. At the present cost, including balance of system cost, this would come to $475,000 for a household of four for one-third of national electricity supply. These PV panels could only supply electricity for about 7 hours a day on average.
Nuclear energy is almost irrelevant to a discussion of the long term global energy future in view of the limited Uranium plus Thorium resources, unless breeder or fusion technologies are assumed. (Trainer 2007, Chapter 9.) The commonly estimated 3.7 – 4 million tones of Uranium would generate a total of only about 600 EJ of electricity, i.e., the equivalent of one year’s demand at the 2100 global rate Garnaut anticipates. Taking the high resource estimates and adding Thorium might multiple the quantity by 6. (Zittel, 2006.)
Even if these formidable quantities of wind and solar energy could be collected and afforded, the main problems surrounding renewables have not yet been raised. These are to do with the integration and storage problems they set. No matter how much wind and PV capacity we build they can provide no energy at all – on a calm night. Output from wind and solar sources rises and falls markedly, and can do so quickly. All PV capacity would come on stream within a couple of hours, but it can take many hours to ramp up a coal-fired plant to full output. (Gas plant can ramp up quicker than coal, but gas use will not be a significant component in a renewable world, because it emits CO2, and gas resources will be largely exhausted later in this century.)
These are not difficult problems when wind and sun contribute a small proportion of demand, say up to 15% each, because adjusting the surplus coal/nuclear generating capacity can accommodate their varying output.
Very large quantities of electricity cannot be stored. Pumped hydro systems are the best option, but can cope with only a small fraction of the demand. Hydroelectricity makes up only about 6% of Australian electricity supply. To store as hydrogen means that possibly 75% of the electrical energy generated would be lost, not including the embodied energy cost of building the elaborate hydrogen generating, processing, storing and electricity regenerating plant. (Bossell, 2004.) That is why a number of people believe we will never have a large scale "hydrogen economy." (See Trainer, 2007a, Chapter 6.) Garnaut devotes one sentence to this enormous storage problem, simply asserting that we can expect it to be solved. (p. 481.)
Note also that if the wind sector is large, for every 1000 MW of wind capacity added up to 1000 MW of coal or nuclear power might also have to be built, to use when the winds are down. This would add greatly to the capital cost of the new system, and clash with greenhouse goals.
If the PV contribution fell from 1.7 EJ to zero in a few hours a load equivalent to about 70 coal or nuclear power stations of 1000 MW capacity, twice our present total generating capacity, would have to be picked up by some other source.
Could solar thermal systems solve the problem?
Because solar thermal systems have the capacity to store heat that can be used to generate later they will probably be the most valuable contributors to a renewable energy world. However it seems that even in Central Australia, possibly the best solar thermal site in the world, these systems will not be ale to provide significant quantities of electricity over the three winter months at an acceptable cost. (For a more detailed discussion, see Trainer, 2008.)
In winter output from trough systems in use in the best US sites goes down to 20% of summer output. The analysis of relevant factors such as direct normal insolation levels, the probable performance of east west troughs in winter, operating and embodied energy costs, and transmission losses from distant sites, seems to leave little doubt that trough systems in winter would not be viable. Average 24 hour flows might be in the region of 10 W/m.
Dishes would be more effective than troughs, but output from the US Mod dish systems corresponds to a continual flow of 18-25 W/metre over a winter month. Performance data on other systems (Davenport, 2008) indicates c. 25 W/m flows. However such figures apply to use of efficient Stirling engines generating electricity at the focus of each dish and these are not applicable to our purpose, which requires heat storage.
The ANU group is exploring the use of ammonia dissociation (splitting into hydrogen and nitrogen) as a way of storing heat from dishes. (Lovegrove and Luzzi, 1996.) They believe the energy efficiency of the chemical process could be .7, and that half the energy entering the dish should be available for generating electricity after storage. This approach is very promising but its net energy efficiency seems to be problematic. For instance if the above Mod etc. winter output figure is reduced to .7 to take into account the ammonia storage process efficiency, and reduced again to take into account the lower efficiency of steam generation compared with Stirling engines, then the winter output would probably be significantly lower than the above 18-25 W/m reported for dish–Stirling systems. Note that at 25 W/m a large power station would need a 40 million square metre collection area, probably costing in the region of $(A)35 billion.
From this gross flow must be subtracted the embodied energy cost of building the collection plant and the heat storage plant involving large and heavy pressurised tanks for the ammonia process. The attempt to assess the embodied energy cost of this system in Trainer 2008 indicates high figures for very large scale systems. Fortunately the Whyalla project being built by Wizard Power will clarify some of these issues. Its developers say they are not yet clear about probable performance and in any case understandably will not make their technical information public.
Also to be deducted are the embodied energy costs of the very long distance transmission lines from central Australia to Eastern coasts. For European supply from Eastern Sahara these could be 15% of energy generated.
Perhaps the most difficult problem for solar thermal systems is set by the need for several days storage of energy in view of winter cloud occurrence. The climate data in Trainer 2008 shows that in central Australia in each winter month there might be two runs of 4 days with little sunlight. Heat storage capacity capable of coping with such runs would be extremely costly in terms of dollars and embodied energy. However if it is assumed that solar thermal is going to solve the intermittency problem set by other renewable source a far greater storage problem is set. This would require solar thermal plant to be equipped with the capacity to generate, accumulate, and store energy output from perhaps three times as much wind plus PV etc. plant as there is solar thermal plant, for several days.
For these reasons it seems that although solar thermal systems will probably be the most valuable contributors to a renewable energy world, they will not be able to guarantee electricity supply in winter even in Australia.
The conversion problem.
Discussions of the potential of renewable energy sources usually fail to take into account the need to convert energy from forms that are available to forms that are needed. Conversion is typically quite energy-inefficient, meaning that much more energy needs to be generated than might appear to be the case.
Electricity accounts for only about 20% of Australian final energy consumption. Garnaut does not explain where the perhaps 40% of energy other than direct electricity and transport energy is to come from, and he therefore does not deal with the losses of energy in conversion from one form to another Nor does Garnaut deal with the fact that sea and air transport cannot be fuelled by electricity.
It should be made clear that little of the global energy budget is likely to come from biomass. (Garnaut does not assume a large contribution.) In Chapter 5 of Trainer 2007a it is explained that if 9 billion people were to have the present Australian amount of transport energy per person from cellulosic ethanol, we would have to harvest a 23 billion ha plantation on a planet with only 13 billion ha of land. (Australia’s biomass potential is likely to be far greater than most countries.)
At the very least the above discussion shows that there are several major difficulties and important issues which need to be resolved satisfactorily before confident conclusions can be arrived at, yet Garnaut does not deal with any of these. He anticipates an Australian electricity consumption that is 7.5 times the present amount, with 7 times the present amount coming from non-carbon based sources, and he anticipates global electricity consumption 10.3 times as great as at present but in a report of 700 pages gives no attention to showing that such huge multiples can be provided. This paper has pointed out that there are a number of impressive lines of argument supporting the conclusion that they cannot be provided.
All the issues raised above were presented to Garnaut as a mid-2008 response to the Interim Report, in the paper Trainer 2008. Receipt of this paper was acknowledged but it is not included in the list of submissions received in the Final Report.
It should be stressed that the points made above are not arguments against renewable energy. We must move to total dependence on renewables as quickly as possible and we can all live well on them, but not in an affluent-consumer-capitalist society.
The Limits to Growth position.
For some 50 years a "limits to growth" analysis of our situation has been accumulating, taking into account many more than energy issues. Its core point is that consumer society is grossly unsustainable because its levels of production and consumption are far higher than can be kept up for long or than all could ever rise to. The quest for affluence and growth is the direct cause of the many alarming global problems now accelerating. Just to note one of these impressive lines of argument, the Australian per capita footprint, around 8 ha of productive land, is about 10 times the amount of productive land that will be available on the planet by 2050 (even ignoring land losses.)
Considerations of this kind support the claim that consumer-capitalist society is not just grossly unsustainable, it cannot be made sustainable. A way of life which is rapidly destroying ecosystems and depleting resources, that is shared by only one-fifth of the world’s people but that all the rest are striving for, that insists on doubling consumption every 23 years, that is possible for a few only because they are taking far more than their fair share and condemning some 4 billion people to poverty – can’t be made sustainable or just.
Even though Garnaut actually briefly discusses the problem of resource limits (p. 69 and Table 3.3), he defers to the dominant ideology regarding the limits theme. He says there is no point considering any option to the greenhouse problem which threatens significant slowing of growth, let alone which involves a transition to much lower levels of production and consumption. He says, "It is neither desirable, nor remotely feasible, to seek to lower the climate change risk by substantially slowing the rise in living standards anywhere, least of all in developing countries. If such an approach were thought to be desirable in some expression of distant and idiosyncratic values, neither Australians, nor people in the developing countries, would accept it.(p. xxl.) Global and national mitigation is only going to be successful if reductions in emissions can be made and demonstrated to be consistent with continued economic growth and rising living standards." (p..)
For several decades some of us have been arguing that the only way out of the global predicament is by huge and radical transition to some form of Simpler Way, in which the core elements are non-affluent lifestyles, mostly small local economies under participatory social control and not driven by market forces or profit, and without any growth at all. (See The Simpler Way website, Trainer 2006.) Such a society would not be possible without equally radical change away from the competitive, acquisitive value syndrome that has driven Western culture for several hundred years.
There is now a small but rapidly growing global movement attempting to build an alternative of this general kind, most evident in the Global Ecovillage Movement and the Transition Towns initiative. Yet, given the overwhelming dominance of the commitment to material affluence and economic growth, the prospects for global transition to some kind of Simpler Way must be judged to be remote. This conclusion is powerfully reinforced by the failure/refusal of governments, media, bureaucracies, people in general, and the intelligentsia to recognise any need to question the commitment to pursuing limitless affluence and growth. Garnaut’s final Report powerfully reinforces the faith that there is no need to think about limits or transition to simpler ways, because alternative technologies will be able to eliminate the greenhouse problem while delivering with vastly greater quantities of energy, and at negligible cost.
Appendix 1. Statements relevant to the adequacy
of renewable energy sources.
- There is a path to Australia being a low-emissions economy by the middle of the
21st century, consistently with continuing strong growth in material living standards.(p. xvii.)
- The solutions to the climate change challenge must be found in removing the
- The interaction of the emissions trading scheme with support for research,
development and commercialisation and for network infrastructure will lead to
successful transition to a near-zero emissions energy sector by mid-century. (p. xliii.)
- Substantial de-carbonisation by 2050 to meet either the 450 or 550 obligation is
- The development of storage technologies and ongoing technical innovation is expected to combine with geothermal energy to begin to replace fossil fuels as the long term solution to our energy needs. Near zero emissions coal technology will have carried out its primary role and remain a significant energy source for some time. (p. 482.)
In Chapter 11 Garnaut makes it clear that he has not examined the potential of particular renewable energy technologies (p. 251) but he regards the most likely of these to be carbon capture and storage. The key numbers, such as those represented in Figure 11.1 stating costs associated with the 450 and 550 ppm targets, cannot sensibly be given without a detailed and convincing explanation of precisely what mix of alternatives might make their contributions and at what cost for each of them. No derivations of these conclusions are given.
- Technological development of any type is difficult to predict. When powerful incentives to innovation are introduced to a market environment, however, human ingenuity usually surprises on the upside. How will this ingenuity manifest itself in the face of high emissions prices and increased public support on a global scale for research, development and commercialisation of low-emissions technologies? We do not know, but there are good reasons to believe that, if we get the policy settings right over the next few years, the technological realities later in the century will be greatly superior to those which, for good reason, are embodied in the standard technology variants of the models used by the Review. (p. 273.)
The footnote says “2 The standard technology assumptions represent a best estimate of the cost, availability and performance of technologies based on historical experience, current knowledge and expected future trends. The standard scenario includes some technological cost reductions through learning by doing and improvements in existing technologies and the emergence and wide-scale deployment of some currently unproven technologies such as carbon capture and storage, hot rocks (geothermal) and hydrogen cars. It does not, however, include a backstop technology in any sector.” (p. 273.) No references are given.
- As one alternative to the standard technology assumptions, the Review
modeled an enhanced technology future, embodying various assumptions of more rapid technological progress, none of which seems unlikely. (p. 252.)
The essentials in the footnote are
- Faster energy efficiency improvements of an extra 1 per cent annually from 2013 to 2030, an extra 0.5 per cent from 2031 to 2040
- More effective carbon capture and storage in response to higher carbon prices
- The share of combustion CO 2 captured increases from 90 per cent to 99 per cent as the permit price rises from zero to $140/t CO2-e
- Faster learning by doing for electricity and transport technologies by increasing the parameter for the learning functions by 50 per cent relative to the standard assumptions over the whole simulation period, and
- Non-combustion agricultural emissions are eliminated when the carbon price exceeds $250/t CO-e. (p. 273.)
Each of the statements in this footnote lacks support, raises major problems and is open to radical criticism. Firstly, the future rate of energy efficiency improvement is highly uncertain and there are poor grounds for assuming particular rates regardless of whether or not the past yields clear figures. We are in an era of great uncertainty, risk and difficulties. Certainly in the short run the now greatly increased incentive is likely to generate considerable gains, but after the low hanging fruit have been picked there will probably be severely diminishing returns. Yet Garnaut assumes likely rates of improvement out to 2040, without supporting argument.
One of the most challengeable aspects of Garnaut’s optimism concerns geosequestration. In this passage he proceeds as if 99% capture and storage will be achieved. (E.g. pp. 273, 482.) It is generally assumed, including by the IPCC, that the limit is 80 -90%. In any case geosequestration can only be applied to that perhaps 50 - 60% of carbon emitting energy generating plant that is stationary. What’s more, Garnaut assumes without explanation that this rate will be possible at the relatively benign cost of $140/t – CO2e.
The third claim is not clear but seems to be, again without explanation, that the figures in the first (energy efficiency) paragraph can be increased by 50%.
In the fourth statement he baldly asserts an outcome which, to say the least, calls for serious examination. How are agricultural emissions to be eliminated, and how is this brought about by the carbon price of $250/t?
In Economic Modeling Technical Paper 1 it is said that there was a detailed treatment of renewable generation in the MMRF modeling, (p. 10), but no information is given.
The most appropriate statement Garnaut makes regarding the core problems is, “Many of the individual technologies are technically proven. Issues of scale, integration and economics are likely to be the greatest challenges. The challenge posed by the scale of the task is the most significant of these.” (p. 495). The reference to the scale of the problem is appropriate but no discussion is offered or referred to.
Again these statements are in effect all the Report includes which refer to, let alone defend the crucial assumption that alternative technologies can solve the problem. In other words almost no case is given and it has been simply assumed that sufficient alternatives can be found to provide more than ten times present electricity supply, while almost completely eliminating emissions.
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