http://solarutopia.org/

(UPDATED, January 2014)

How much Fossil Fuel is needed for Solar Transition & Which one should be used?

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Let’s first be clear that solar transition must be parasitic on existing energy supplies, just as the industrial fossil fuel revolution was parasitic on biomass energy, so-called plant power, until it replaced the former supply with sufficient capacity. The higher the EROEI* value of the wind/solar technology used, the less unsustainable presently-used-energy is needed to effect the solar transition. Mainly because of its lower carbon emission footprint compared to coal, the preferred fossil fuel to make a solar transition is petroleum (oil and natural gas, but excluding tar sands, fracked natural gas, and dangerous drilling on deep water continental shelves). Just how much petroleum is needed in our preferred solar transition model to insure a steadily increasing global energy supply with a minimum 3.5 kilowatt/person globally, accompanied by an early phaseout of coal, nuclear, big damaging hydropower and most biofuels?

Recall this model has the following assumptions: conservative value of EROEI = 20, 20-30 year transition, and at its completion 2x the current global energy delivery is generated comprised of all wind/solar, no fossil fuel/nuclear/biofuels. We estimate that no more than 40% of the proven conventional reserves of petroleum (oil and natural gas, excluding tar sands and fracked gas reserves) is needed, roughly 7 ZJ. The latter requirement will be reduced as higher EROEI wind.solar technologies are developed and put in place in this transition.

Yes, at the culmination of this solar transition a global increase in energy would be delivered to the world not a decrease, with many countries in the global North such as the U.S. decreasing their wasteful consumption, while most of humanity in the global South get a significant increase. To reach the minimum 3.5 kilowatt/person now (7 billion people) requires a delivery equivalent to 25 Tera Watts, with the present delivery equal to 16 Tera Watts (Energy consumed = Power x Time, so just multiply 16 TW by 1 year to get the energy consumption per year, units TWyears). The factors impact on this estimate are discussed in our Report posted on solarutopia.org.

In a robust solar transition, generating progressively increasing global energy delivery over 25 years, with an EROEI value of wind/solar power equal to 25 (same as their lifetime in years) then a total of 18.5 ZJ is consumed, with RE-derived energy generating 54%, and industrial carbon sequestration energy requiring 5 to 20% of the total. This requirement would of course be reduced by the use of agriculturally-driven carbon sequestration into the soil.

Here is the function used for progressive phase-out of non-RE energy sources over the assumed 25 year transition period, with t being the time in years:
FF = 1 – 0.015 t – 0.001 t2 ; ∫FFdt from t = 0 to 25,
gives a non-RE energy sources equal to 15.1 times the present annual global energy consumption level (18 TW year = 0.57 ZJ) or 8.6 ZJ.

Smil (2008) cites Ahlbrandt et al. (2005), who estimated the proven conventional natural gas reserves equal to 7.24 ZJ (55% of 415 Tm3). With an assumed 1,354 bb for the proven conventional oil reserve (equivalent to 7.9 ZJ) this gives a total equal to 15.1 ZJ for proven conventional oil plus gas reserves (“petroleum”). Then the 8.6 ZJ for non-RE energy computed from our robust solar transition is equal to 57% of this proven petroleum reserves. (The ‘proven’ reserves cited do not include tar sands, oil shale or fracked gas). From Figure 2, Hansen et al. (2013), the total of “estimated” plus “recoverable resources” of conventional oil and gas can be computed, roughly equivalent to 26 ZJ (14 ZJ gas, 12 ZJ oil*). For this estimate, the 8.6 ZJ computed from our robust solar transition is equal to 33% of potential energy of recoverable conventional petroleum still in the crust. Since coal, nuclear power as well as hydropower and biofuels now contribute to global energy consumption, and will during their phase-out in a full transition to RE, the computed petroleum contribution is a maximum.
* Assumed values of 51.4 Gt CO2/ZJ for gas, 68 Gt CO2/ZJ for oil.

References cited:
Hansen et al., 2013, Assessing ‘‘Dangerous Climate Change’’: Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature. PLOS ONE 8 (12) e81648.

Other references are given in Schwartzman and Schwartzman (2012), available for download on this website.

Aggressive energy conservation and rapid phaseout of coal use in energy-wasteful countries such as the U.S. is imperative, and must start in the very near future to begin radical reduction in carbon emissions. Further, as the solar transition proceeds, energy conservation in the gobal North would free up petroleum needed for rapid solar development in the global South. Oil rich countries in the Mid-East and South America (e.g., Venezuela) will be valuable partners in this solar transition by providing the needed petroleum. We are persuaded that this hopeful scenario requires global demilitarization a necessary condition for a global cooperative regime of transition. But if we wait too long without making a vigorous transition, then and only then will we likely face the gloom and doom scenario of Peak Oil and the virtually inevitable onset of catastrophic climate change, barring near future revolutionary solar technologies with much higher EROEIs. Nevertheless, carbon sequestration powered by agroecologies and solar power is imperative, and must start asap to have any hope of preventing the onset of catastrophic climate change (“C3″). The longer the excess carbon dioxide remains in the atmosphere the more likely the tipping points for C3 will be reached, therefore radical and early cuts in carbon emissions and carbon sequestration go hand in hand. And now we may have only 5 years left for global carbon emissions to peak, to be followed by radical cuts (“World headed for irreversible climate change in five years, IEA warns If fossil fuel infrastructure is not rapidly changed, the world will ‘lose for ever’ the chance to avoid dangerous climate change” , Fiona Harvey,guardian.co.uk, November 9, 2011).

* EROEI is the Energy return over energy invested ratio, i.e., how much energy does the technology such as a photovoltaic array or wind turbine generate in its usable lifetime divided by the energy needed to construct it and maintain it.

By, David Schwartzman

(Updated 1/10/14)
Carbon-sequestration from the atmosphere must be a component of a Solar Transition

By David Schwartzman

Following Hansen et al.’s (2008) analysis, a prevention program to have any chance of avoiding catastrophic climate change (C3) must include carbon-sequestration from the atmosphere to achieve an atmospheric CO2 level at or below 350 ppm (it is now 400 ppm) ASAP. His group recommends a 6% cut/year in fossil fuel consumption starting now, with 100 Pg of carbon sequestered from the atmosphere by reforestation from 2031-2080 leaving 350 ppm CO2 in the atmosphere by 2100 (Hansen et al., 2013).
Lal (2010) estimates 2-4 Pg per year of carbon from the atmosphere could be sequestered globally as soil carbon from the atmosphere using agroecological approaches. Assuming a rate of 2 Pg/year, in 50 years 100 Pg of carbon could be sequestered from the atmosphere.

A likely complementary approach is solar-powered industrial carbon sequestration from the atmosphere. For an energy requirement of 110 to 442 KJ/mole CO2 (House et al., 2011; Zeman, 2007), 100 Pg of carbon could be industrially sequestered from the atmosphere requiring 0.91 to 3.7 ZJ, equivalent to 1.6 to 6.5 years of the present global energy delivery (18 TW). In a robust solar transition, with an EROEI value of wind/solar power equal to 25 (same as their lifetime in years) then a total of 18.5 ZJ is consumed over 25 years, with wind/solar generating 54%, and industrial carbon sequestration energy requiring 5 to 20% of the total (see methodology and assumptions in How much Petroleum is needed for this Solar Transition?). This requirement would of course be reduced by the use of agriculturally-driven carbon sequestration into the soil.

References

Hansen, J., Sato, M., Kharecha, P., Beerling, D., Berner, R., Masson-Delmotte, V., Pagani, M., Raymo, M., Royer, D.L., and J.C. Zachos, 2008: Target atmospheric CO2: where should humanity aim? Open Atmos. Sci. J., 2, 217-231.
Hansen et al., 2013, Assessing ‘‘Dangerous Climate Change’’: Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature. PLOS ONE 8 (12) e81648.
House, K.Z., Baclig, A.C., Ranjan, M., van Nierop, E.A., Wilcox, J., and H.J. Herzog, 2011, Economic and energetic analysis of capturing CO2 from ambient air. PNAS 108, No. 51: 20428-20433.
Lal, R., 2010, Managing soils and ecosystems for mitigating anthropogenic carbon emissions and advancing global food security. BioScience 60: 708-721.
Zeman, F., 2007, Energy and material balance of CO2 capture from ambient air. Environ. Sci. Technol. 41: 7558-7563.

(A Critique of Michael Lind’s ‘Everything you’ve heard about fossil fuels may be wrong’)
(Posted at: http://www.solidarityeconomy.net/ & http://progressivesforobama.blogspot.com)

By David Schwartzman

It’s the other way around. Nearly everything we hear from Lind in this Salon piece (May 31, 2011) is wrong, except for his argument that huge potential reserves of fossil fuel will likely prove peak oil boosters being big exaggerators. The latter news may not be wrong, but it is hardly comforting.

More importantly, Lind’s uninformed dismissal of solar power as a real alternative is typical misinformation that we can expect from the fossil fuel/nuclear lobbies. And his misplaced optimism regarding the unlikelihood of catastrophic climate change (C3) from rising levels of greenhouse gas is still another unsubstantiated claim. We’re used to hearing this from scientifically illiterate global warming deniers. Why Lind chooses to join them is a puzzle.

Whenever peak fossil fuel usage occurs–either from the exhaustion of reserves or replacement by alternatives–the Age of Fossil Fuels will soon be over. Human civilization and existing biodiversity will simply not sustain ever rising levels of atmospheric carbon dioxide and methane. We have precious little time, if any at all, to radically reduce carbon emissions and replace fossil fuel energy with solar. This is fundamentally why Lind’s born again fossil fuel enthusiasm is so misplaced. If he has the facts and science to claim otherwise, he should produce it. As a scientist involved in this field, I don’t think he can.

Lind’s enthusiasm for shale-derived natural gas via ‘fracking’ (the hydraulic fracturing of underground shale formations with toxic brine) is truly delusional. Ignoring the growing evidence for fracking leading to serious groundwater contamination, he attempts to rebut Howarth’s study recently published in a peer-reviewed journal Climatic Change. Howarth argued that fracking could well be worse than even burning coal, the fossil fuel with the highest carbon emission per energy generated, because this technology results in methane leakage directly to the atmosphere.

Since methane is a very potent greenhouse gas, direct leakage is always an issue in the extraction of natural gas, which is itself the lowest carbon emitter when completely burned. Lind cites the WorldWatch critique which at best demonstrates that methane leakage from coal mining was overlooked in Howarth’s study. So the greenhouse impact of coal use may be worse than anyone thought.

The choice, however, should not be between two fossil fuels with the greatest greenhouse and environmental footprint. Rather it should be to wisely use the minimum necessary fraction of the remaining reserves of conventional petroleum, including non-fracked natural gas, to make a rapid transition to a fully solar power infrastructure while we still have time to avoid C3. This transition is strongly supported by WorldWatch, aside from the controversy around fracking. (Lind’s other potential source of natural gas, extracted from methane hydrates, would likely have the same problem with direct leakage to the atmosphere. I suppose we should at least be grateful for his not mentioning tar sands or oil shale, both with huge negative environmental and greenhouse impacts).

Lind bubbles with delight at the prospect of abundant fossil fuel subverting organic agriculture (really agroecology informed by cutting edge science) and facilitating the spread of human populations outward from cities into forests and grasslands. Biodiversity destruction and poison dispersal gone wild! At least he has made clear that his “green” values refer to the Almighty Dollar, i.e., accumulation of capital by the fossil fuel industrial complex rather than to any semblance of environmental protection.

Lind says “The scenarios with the most catastrophic outcomes of global warming are low probability outcomes…And if the worst-case scenarios for climate change were plausible, then the most effective way to avert catastrophic global warming would be the rapid expansion of nuclear power, not over-complicated schemes worthy of Rube Goldberg or Wile E. Coyote to carpet the world’s deserts and prairies with solar panels and wind farms that would provide only intermittent energy from weak and diffuse sources.”

The worst-case scenarios may not be plausible for Lind, but they are for a growing number of climate scientists, notably Jim Hansen. IPCC predictions keep on being shown to be too conservative. For example, Hansen has recently highlighted the likelihood that disintegration/melting of the ice caps is non-linear, with future sea level increases being underestimated if carbon emission do not cease soon (Hansen and Sato, 2011). Empirical evidence mounts for ocean acidification and extreme weather fluctuations being driven by rising atmospheric carbon dioxide levels and global warming respectively. And Hansen’s “safe” upper limit of 350 ppm for atmospheric carbon dioxide (Hansen et al., 2008) may well be too high, while the level now is 395 ppm (http://www.guardian.co.uk/environment/2011/may/31/carbon-levels-peak). Only thermal inertia of the ocean may give us a small window of time to act, perhaps a decade or two. Carbon sequestration using permaculture and solar energy will be required to avoid C3 even if carbon emissions decline rapidly.

Lind’s prescription for nuclear power is another case of delusion. Aside from the negative impacts of the nuclear fuel cycle, unmentioned by Lind, and catastrophic accidents, the quickest way to replace fossil fuel dependence is building wind turbines, installing photovoltaics and concentrated solar power in deserts–all proven technologies far less complicated and safer than the nuclear option. And these solar technologies generate more jobs and are far cheaper than the nuclear option (or even coal) if the huge subsidies to the nuclear/fossil fuel industries are taken into account.

My older son Peter and I recently published a peer-reviewed “A Solar Transition is Possible” study (http://iprd.org.uk and on our own website http://www.solarutopia.org). We modeled the conversion of our present global energy infrastructure to a fully renewable alternative, inputting properties of current state-of-the-art renewable technology, notably its EROI (energy return on energy invested) and lifetime. Energy investments come from the depletable (i.e., non-renewable) energy sources dominated by fossil fuels as well as the growing renewable infrastructure.

We find that we can replace the entire existing energy infrastructure with renewables in 25 years or less, so long as EROI of the mixed renewable power infrastructure is maintained at 20 or higher, by using merely 1% of the present fossil fuel capacity and a reinvestment of 10% of the renewable capacity per year. Furthermore, in this time frame, for an annual contribution equal to 2% of the present energy fossil fuel capacity, the global power capacity can grow relative to the present level so as to provide energy consumption per person levels sufficient for every one on the planet to live at high human development requirements, while radically reducing carbon emissions. Even faster replacement times result from higher dedicated commitments of depletable energy and energy invested from the growing renewable capacity.

Lind’s alleged intermittency problem with solar has been convincingly addressed by Stanford University Professor Mark Jacobson and others. Adequate baseload energy is achieved once the solar infrastructure grows using smart grids and becomes more diverse. Meanwhile energy storage technologies and petroleum can contribute to baseload.

While we did not include energy conservation in our model, making our projections conservative (not politically!), aggressive energy conservation is imperative, especially in the United States and other countries of the global North. We can all live better with a sharp reduction of wasteful consumption, breathe clean air, drink clean water and eat organic food. Nevertheless, we are arguing strongly for a global increase in power capacity, employing clean energy and not fossil fuels or nuclear power, to insure every child born on this planet has the material requirements for the highest quality of life.

The obstacles are obvious. First is the huge waste of resources and funds to the annual $1.5 trillion global military budget, followed by the disinformation spread by the Military Industrial Fossil Fuel Nuclear Complex with authors in its service such as Michael Lind.

References cited

Hansen, James E. and Makiko Sato, May 5, 2011, submitted. Paleoclimate Implications for Human-Made Climate Change. http://arxiv.org/abs/1105.0968

Hansen, J., Mki. Sato, P. Kharecha, D. Beerling, R. Berner, V. Masson-Delmotte, M. Pagani, M. Raymo, D.L. Royer, and J.C. Zachos, 2008, Target atmospheric CO2: Where should humanity aim? Open Atmos. Sci. J., 2, 217-231, doi:10.2174/1874282300802010217.

Howarth, Robert W., Renee Santoro and Anthony Ingraffea, 2011, Methane and the greenhouse-gas footprint of natural gas from shale formations. Climatic Change 106:679–690.

Lind, Michael, 2011 (May 31), Everything you’ve heard about fossil fuels may be wrong,

http://www.salon.com/news/env/energy/?story=/politics/war_room/2011/05/31/linbd_fossil_fuels

http://blogs.worldwatch.org/natural-gas-versus-coal-clearing-the-air-on-methane-leakage/Natural Gas versus Coal: Clearing the Air on Methane Leakage

David Schwartzman is a Professor in the Department of Biology at Howard University in Washington, D.C. His research focus is on biogeochemistry, astrobiology, origin of life, and environmental policy. He is a member of the International Committee, Green Party U.S., DC Metro Science for the People, and Metro DC chapter of the Committees of Correspondence for Democracy and Socialism, and an activist in the DC Statehood Green Party . He is the author of Life, Temperature, and the Earth: The Self-Organizing Biosphere. Websites: http://www.solarutopia.org and http://www.redandgreen.org

The following exchange originally took place on a listserv….

FROM Maggie Zhou: David, I am sorry but I’ve discussed this with you several times, I really think the model you keep promoting is a self-deceiving fantasy that is dangerous for all of us to believe in.

David Schwartzman’s RESPONSE: Rather than a self-deceiving fantasy we submit this is a realizable transition that can and should be achieved if we have any hope of preventing catastrophic climate change and of providing the minimum energy needed for everyone on this planet getting the state of the science quality of life. Everyone, yes even the majority of humankind now living the global South suffering from energy poverty. And as we emphasize this transition will not happen by business as usual market-driven, rather will require radical changes, including the dissolution of the Military Industrial (Fossil Fuel, Nuclear, State Terror) Complex (“MIC”). (go to our Statement on solarutopia.org and our Report, plus several of my own papers in CNS).
The real self-deceiving fantasy is to believe that we should simply promote a radical reduction of energy globally and expect working people and unemployed to support such a future. Rather, fighting for clean energy, green jobs, fighting to eliminate MIC as you have so ably done in your activism, is class struggle that can succeed.

FROM Maggie: In your report you even acknowledge there may be a problem with rare earth metals availability for this huge scale wholesale transition to solar+wind, with no reduction of current global energy production, but instead a doubling of total production! Yet you do not examine this essential problem at all. Extracting for rare earth metals is extremely damaging to the env, and there is limited supply of it, which is why western countries are so annoyed when China announced reduction plans of its imports (partly to keep it for themselves, partly due to closing down of dangerous and highly polluting open-pit mines).

David’s RESPONSE: Your concern is very well taken. Any solarization, including the mining of REE, making PVs, siting wind turbines, must be subject to social management and design, starting with the local going to the global, to address the negative impacts you are referring to, corporate-managed versus people-managed. I looked at the known reserves of REE and they are sufficient to build present-technology wind turbines contributing on the order of 10TW of global power. Further, transition to solar will also reduce energy used for mining by facilitating recycling without the concomitant negative impacts of using fossil fuels to do the same. Similarly, we can plausibly expect technological innovations to phase out the need to use rare metals like Nd (e.g., see http://www.terramagnetica.com/2009/08/07/10-mw-and-beyond-are-superconductors-the-future-of-wind-energy/).
But to demand that solar have zero negative impacts is the real fantasy. Putting passive solar on a roof opens up the risk of falling off and breaking your neck, indeed repairing bridges, expanding decentralized solar power, all neceessary, will result in such accidents. We should fight for full and expanded enforcement by OSHA, just as we protect the workers and community from potentially negative impacts of making PVs etc. ALL of this requires Class Struggle!

FROM Maggie: You also have not examined the NF3 emission associated with solar panels, or SF6 with wind farms. Both are thousands of times more potent than CO2, and lasts thousands of years. At least NF3 is likely unavoidable.

David’s RESPONSE: You point to potentially important greenhouse gas contributors associated with present, too weakly regulated solar production. But a qualitative argument alone means little, show us the studies that demonstrate a comparable greenhouse forcing for even present PV and wind turbine production to fossil fuels for the same power capacity created. Here is one study which shows how these emissions for PV could be significantly reduced: de Wild-Scholten, et al., FLUORINATED GREENHOUSE GASES IN PHOTOVOLTAIC MODULE MANUFACTURING: 22nd European Photovoltaic Solar Energy Conference, Fiera Milano, Italy, 3-7 September 2007 Version: 30 August 2007
Further, the life-cycle studies cited in our report demonstrate that greenhouse forcing from PV and wind are much lower than fossil fuels. Nevertheless, your point about potential future contributions from these trace gases must be addressed in a solar transition!

FROM Maggie: You assume a minimum of 3.5 kilowatt per capita for high life expectancy for everyone in the world, but even in those countries currently falling on the pivot of the life-expectancy/energy curve, this amount of energy is not all used in ways that strengthens their life expectancy. Some of it is still wasted on productions and consumptions that are harmful. So the real need is far less, and we certainly should not accept it that the planet WILL swell to 9 billion people, if we are a species that thinks it’s any more intelligent than rats or yeast to be able to do something about its uncontrolled multiplication!

David’s RESPONSE: First your last point which sounds like a reprise of neo-Malthusian arguments. Eliminating the worst poverty and disempowerment of women is the proven approach to stabilizing population. The critical material requirement is to also eliminate energy poverty.
As for your first point, to be sure, energy consumption per capita needs to be corrected for the unequal consumption by class in a nation. Nevertheless, given the small percentage of the number of very rich-energy consuming folk, the correction you call for is not significant, especially given the caveats we discuss in our report. For example, if 1% of the population consumes 10 x the energy of the bottom 99%, the required 3.5 kilowatt/person for the bottom 99% goes down to 3.1 kilowatt/person. Neverthess, there is a very strong causal correlation between life expectancy and energy consumption per person which is now recognized by many scholars (Smil, UN, even Richard Heinberg). Our challenge with the global North is fighting for a robust regulation regime to rapidly phase out carbon emissions, including very aggressive energy conservation combined with a maximum of decentralized solar power capacity, but for the global South we must fight for a rapid and substantial increase in solar power to meet the approximately 3.5 kilowatt/person minimum required for the state of the science life expectancy and all that goes with it. Again Cuba is an excellent example of how a society transitioning to ecosocialism is still a society of scarcity and energy poverty (because of the unrelenting campaign of hostility and aggression from US imperialism) look at her life expectancy, now tied with the U.S. and Denmark at 36 in the world.

FROM Maggie: Finally, this talk about being able to grow all the pot we want reveals you are not taking it to heart yourself about the equal sharing per capita of 3.5 kilowatt for everyone on the planet. The US currently far exceeds this consumption level per capita, so we’ll have to reduce dramatically our electricity consumption, even if it’s 100% solar.
The reason why I keep criticizing you on this is because I see this as an example (same goes for the “single-occupant electric SUVs” – excuse me?) of the callous green capitalist mantra of just-convert-everything-to-renewable-and-we’ll-be-fine. Coming from a Green person and an academic it’s especially damaging given the level of trust socially responsible people likely place on you. We must advocate dramatic reductions in consumption as a society, and a complete shift of what to produce and consume, and how to. Renewable energy all come at a cost to the environment as well, so only a small amount of it (at least in the short run) should be used to ensure the most essential needs. Most importantly we have to acknowledge that there is a climate/ecological emergency, and our societies have to make the necessary changes in far shorter time than decades.

David’s RESPONSE: Again, we strongly advocate aggressive energy conservation especially in the global North, like the U.S. with its very wasteful pattern of consumption, far above the minimum needed to achieve the roughly 3 to 3.5 kilowatt/person. Again with such a reduction we can all live better, clean air, clean water, organic food, mass transit instead of SUVs etc.
To be sure we must start now, but If you think we can make the necessary changes in a far shorter time than a few decades, please show us how? Everyone should migrate to the woods and live without electricity in a log cabin? (the die-off school of Peak Oil)

David ADDED:
I misstated a point in my previous message. I meant to say:

Nevertheless, given the small percentage of the number of very rich-energy consuming folk, the correction you call for is not significant, especially given the caveats we discuss in our report. For example, for an overall energy consumption per capita of 3.5 kilowatt/person of a nation, if 1% of the population consumes 10 x the energy of the bottom 99%, the actual consumption for the bottom 99% goes down to 3.1 kilowatt/person. Reducing income/energy consumption gap alone would of course help deliver higher energy to the 99% without increasing the energy consumption by this nation. However, this example shows how energy poverty is still very relevant wrst global requirements, even with the inequality prevailing in most countries in the global South. The Cuban example shows how even a very equal society in the global South still suffers from significant energy poverty.

More comments:

One other consideration regarding the future of PV technology: new thin film PVs are being developed including those that don’t require rare and toxic metals like Cd and In. We can reasonably expect very cheap and efficient thin film PVs using common metals like Ti, Fe becoming available in the near future. Here is a calculation I published in one of my CNS papers (details are available on request): Assuming solar insolation levels available in N. Europe, if 15 percent of present world rooftop area were to be used to site photovoltaics with an assumed conversion efficiency of 20 percent (the current value of Si PVs), the current global electricity power capacity would be created. Of course we should not expect “green” capitalism to automatically drive this energy revolution in time to prevent catastrophic climate change (C3).

One imperative dictated by the physics of climate: to increase the chances of C3 prevention, the challenge we face is to curb C emissions radically and rapidly AND promote effective solar-powered C-sequestration sooner than later to reduce the current 390 ppm (soon to be greater) CO2 level to below the safer 350 ppm level (see Jim Hansen’s papers). I suspect this will require industrial solar-powered sequestration on a massive scale coupled with a rapid shift to agroecologies (permaculture). The longer we leave the CO2 in the atmosphere the greater the chances we will reach the tipping points to C3 because of the response of the ocean coming into thermal equilibrium with the greenhouse forcings. This is an additional argument for building a global solar power level to over 20 TW delivery capacity. We also need extra power to clean up the huge legacy of destruction produced by MIC. See our report for more details.