Saturday 11 June 2016

Once More on the Viability of Renewable Energies

For some years in the past, I more or less withdrew from the debate/discussion on the above subject. We were not making any progress. The optimists continued repeating like a religious mantra ("100% renewables") that in 20-30 years all energy needs of human society will be (can be) supplied by renewables. No arguments of the skeptics like me were being taken seriously. I gave up, saying "Just wait another 10 years! By then the issue will be decided." I started saying that about five years ago. But already now it appears that the optimists are no longer so sure. In an article written by Ugo Bardi1, a member of the Club of Rome, also published in a popular Indian internet journal (, I read that more and more people, even experts, are expressing their skepticism. So I again joined the debate.
    Ugo Bardi and other optimists of today are of course still expressing optimism. But they are no longer as euphorically optimistic about renewable energies as, for example, the late high priest of solar energy euphoria Hermann Scheer (former president of Eurosolar). They are now roughly saying, 100% renewables is possible, but it will not be easy, and we must in future change the way we are living today in industrial societies; we must be satisfied with less. That is some progress. But the illusions still remain.
    So I intervened again, with two comments and a letter to a friend. They are appended below with several references.

Sarkar's 1st comment:

I just read Ugo Bardi's article with interest. I am not a scientist, never tried myself to measure the EROEI or the EPBT (Energy Payback Time) of any energy technology. But I am very interested in the question, for obvious reasons. I am trying to keep abreast of the news on this matter. But I am not convinced that the EROEI of photovoltaic technology is that high (Bardi estimated 11-12).
    The proof of the pudding is in the eating. If the assertion of Bardi were true, then there would not be any reason at all for
India, much richer in sunshine than Italy, to still build new (I stress new) coal-fired power plants and to import huge quantities of coal and oil and pay high amounts of precious foreign exchange to foreigners. If the matter were that simple, the problem of global warming would have been solved long ago.
    The first author of the paper Bardi refers to appears to be an Indian (or of Indian origin). Why doesn't he go to New Delhi and persuade the Indian government to cover all desert and semi-arid areas of the country with photovoltaic panels? After all, only a few months ago, at COP21, India was heavily criticized for obstructing the process of reaching a global agreement.
    I think most studies that paint a rosy picture in this question tend not to count all (I stress all) energy costs (investments) needed in building a solar module. That is why, already in 1991, some researchers who, commissioned by the EU, made a study in Europe came to the conclusions (a) that in European climates, the average EPBT for photovoltaic modules were as low as 1.2 years and 2.1 (meaning EROEI was very high) and (b) that the EPBTs of the PV technologies developed till then were by and large "comparable to that of large-scale electricity production in fossil and nuclear power plants
".(quoted in: see note 4) We know that PV technologies, in spite of all subsidies and sundry favors, still cannot compete with fossil fuel based technologies of producing electricity.
    How researchers in this field ought to count all energy costs of an energy technology (not to be mixed up with money costs) can be read in a paper of Nicholas Georgescu-Roegen on this subject (see note 3)

Sarkar's 2nd comment:

Dear Ugo, in real life it is very useful/necessary to take a round-about (indirect) way to reach a goal when there is no direct way to reach it. It is even scientific.
James Lovelock (of the Gaia hypothesis) did that when he (plus many other scientists) was asked by NASA to figure out whether there could be life on the Mars. He could not land on the Mars to find out the answer. So he asked, how would the atmosphere of Mars be if there were life on that planet.
    We are today faced with a vital real-life question: Can someday in near future fossil fuels be replaced by photovoltaic energy etc.? We cannot answer the question directly by "rigorously" counting the calories of energy invested in manufacturing all the equipment of PV technology because it is nearly impossible. That is why every researcher is guessing. Guesstimates are anything but rigorous. That is why so many different results are on the table. Nobody, for example, really knows what proportion of the energy costs of manufacturing the truck that is transporting the sand to the silicon smelter should be included in the energy costs of manufacturing a PV module. I do not want to write more on this point. Georgescu-Roegen (1978) put it more clearly.

A Letter to a Friend


Dear Johny,

many thanks for sending this article.2 I, like all of you, got the reference through reading the comments on Ugo Bardi's article in Cassandra's Legacy.2
    I think the whole debate is a little out of focus. Which end of the formula should we pay more attention to? To ER or to EI? Counting both exactly would be good. But only ER can be counted exactly by attaching meters to every PV-module. Nobody can deny that ER may improve in course of time through technological improvements in the modules. But that does not help much because it is very difficult to exactly count the EI (energy invested on pro rata calculation basis) in every module. Even if you are satisfied with average figures at any given latitude and in any given climate zone, it is very difficult. How difficult it is can be realized if you ask the question: where should one begin the counting? Here a reading of Georgescu-Roegens 1978 paper3 is very important. (I did that in the 1980s and summarized GR's argument in my book.4) If one reads it, one would realize that most modern estimates of EI per module are wrong.
    My new idea has been to come to a provisional conclusion on the basis of a round about method following James Lovelock's method of intelligently guessing whether there could be life on the Mars (referred to in my second comment on Bardi's article. See above.). Coming to a provisional conclusion reg. the EROEI of both PV and Wind-turbine technologies is important because, all people agree, burning more and more fossil fuels must end if we really want to save the planet. So I asked (in my opinion the very important question) why India still wants to double coal extraction in the next five years although it is among the most sun-rich countries of the world.5 It must do that because Indian energy experts & engineers are not convinced that the EROEI of PV technology is sufficiently high to justify leaving India's coal wealth in the ground.
    Another point I made (see my article on Krugman's folly6) is that the energy cost (EI) of producing PV or wind energy modules (as distinct from money cost) is continuously and inevitably rising (even if you leave aside the equipment and processes for storing and distributing the renewable energies) because the materials (including coal and uranium) that are used to build/manufacture all the equipment are becoming increasingly difficult to access.
    And finally, the difference between
feasibility and viability, that we should learn from Georgescu-Roegen. Renewable energies are feasible but not viable. This point was indeed made in a comment (by "foodnstuff")7 on Bardi's article. But it was unfortunately ignored by all (except me).
    Finally, I request you to retrieve the paper of Georgescu-Roegen and publish it in some website (it was published before the internet age). Then it can be circulated without any problem.
    I am also going to post this piece in your Simplicity Forum. But before doing so I must add the references. For that I need some time. In the meantime I am sending it to you and ...  as an e-mail.

With warm regards


Notes and References:

1. Ugo Bardi (2016) "But What is the Real Energy Return of Photovoltaic Energy?"

2. "Energy Return on Energy Invested (ERoEI) for photovoltaic solar systems in regions of moderate insolation", by FerruccioFerroni a,n, RobertJ.Hopkirk
Energy Policy
journal homepage:

3. Georgescu-Roegen, Nicholas (1978) "Technology Assessment: The Case of the Direct Use of Solar Energy", in Atlantic Economic Journal, December.

4. Sarkar, Saral (1999) Eco-Socialism or Eco-Capitalism? London: Zed.
5. Sarkar, Saral :
A Historic Event or a Fraud?....

6. Saral Sarkar (2014)
Krugman's Illusion …..

7. Foodnstuff : comment/questions:

foodnstuffMay 23, 2016 at 7:53 PM

I still want to know if the following can be done and does the EROEI quoted include it all (plus extra energy demand I haven't thought of):

(1). Mine the raw materials using equipment powered by solar panels.
(2). Transport and convert metal ores, eg bauxite -> aluminium, using equipment run by solar panels and in a factory built using the energy from solar panels.
(3). Make the finished panels in a factory run by solar panels, including building and maintaining the factory.
(4). Transport, install and maintain the solar panels using equipment running on solar panels.

All this is presently being done with the energy from fossil fuels.
How will it be done when they are gone?