20150419 The PV Energy cliff

A petición de algunos lectores, introduzco los últimos intercambios han tenido lugar últimamente sobre los ya habidos hace un par de años sobre el asunto de la TRE fotovoltaica, a raíz de la publicación del libro “Spain’s Photovoltaic Revolution. The Energy Return on Investment” que publicamos en 2013 un servidor y Charles Hall.

Confío en que los lectores puedan sacar sus propias conclusiones e incluyo los comunicados habidos hasta la fecha. Seguramente seguirá saliendo alguno más y se irá incluyendo en este artículo.

Se incluyen en inglés sin traducción, por la falta de tiempo para traducirlos al castellano. Lamento que los que no puedan leer en este idioma se lo pierdan y dejo abierta la puerta por si alguien tiene interés en traducirlos.

En el blog de Alice Friedemann, una periodista independiente especializada en energía, titulado Energy Skeptic (www.energyskeptic.com) se publica un artículo titulado “Tilting at Windmills, Spain’s disastrous attempt to replace fossil fuels with Solar Photovoltaics”,

donde se hace un repaso exhaustivo del libro que publicamos Charles Hall y yo.

Alice asistió a unas conferencias sobre energía en la universidad de Stanford en EE. UU. Uno de los temas tratados fue la conveniencia y necesidad de estandarizar los procedimientos y metodología para medir la Tasa de Retorno Energético (TRE o en inglés Energy Return on Investment o EROI). A juicio de Alice, los elementos que se supone deberían estudiarse como costes energéticos de la fabricación, puesta en marcha y operación de los sistemas energéticos no quedaban claros. Así que preguntó al panel si no habían pensado en algunos de ellos que habían tenido en consideración Prieto y Hall. Les dejo con el propio comentario de Alice sobre aquellas jornadas:

April 1, 2015 update: Criticism of Prieto and Hall
I was at a net energy conference at Stanford University the past two days. The hoped for outcome is a new net energy think-tank that would standardize net energy by having a specific way researchers must conduct their studies, which LCA or other data tables are most-up-to-date and should be used, what assumptions they must state, and so on. If researchers strayed from this format or added additional material, they’d need to say why.
The reason this needs to be done is because policy makers don’t take EROI studies seriously. Nor should they since they’re too easy to game by proponents (i.e. not counting the energy to make steel because it is 100% recycled, cherry-picking the best performing wind or solar farms over the best performing time period, etc). Policy makers can’t be expected to make policy decisions or recommendations when EROI studies of a renewable ranges from 4 to 115.
Meta-studies can’t be done either because there is too much missing data, and/or unstated assumptions, and/or different models used, and rarely is real data available, since private companies don’t have to, and don’t want to reveal their true performance, operation, and maintenance costs or they’d get less investment and lower stock prices.
Yet even at the conference several EROI papers were not clear about their boundaries. Long after the artificial photosynthesis presentation it came up that the outside boundary was set at 300 feet outside the factory gate. Earlier they said the best guess EROI was 1.66, clearly if storage of the hydrogen produced, and delivery to the customer were added, the EROI is probably negative. The researcher implied that trying to combine the hydrogen with CO2 to make liquid fuels would be negative at this stage. There may be a good reason why the boundary is 300 feet away, probably they assume that there’s a refinery nearby using the hydrogen to upgrade heavy or tarsand oil.
By the end of the conference I was a bit frustrated at the lack of discussion of boundaries.
This has been the main problem for 40 years and one of the big reasons why studies come up with such different results.
So I asked the panel what they thought should be done about the boundary issue. For example, ethanol studies using narrow boundaries found higher EROI values than those with the widest boundaries, which often found a negative EROI. Then I said that if there’s to be a discussion of how to set boundaries, I recommended Spain’s PV revolution by Prieto and Hall which used real production data over several years rather than models as a good way to decide what to include or not include, and why, because I thought the boundaries should be as wide as possible. Also, since what you’re proposing is a mostly electric world, does that mean new standards will include the electricity used to make cement for the windmill and roads it travels on, the electricity to make the steel and fiberglass, and the electricity to make electric mining trucks and the electric delivery trucks that deliver the windmill? And what would that electric delivery truck look like anyhow?
I had the strong impression this was not a welcome question. No one leaped to answer, and finally one of the panelists said that the boundaries ought to be wide but that this question was best talked about over a glass of wine.
After this session one of the speakers, Marco Raugei, at Oxford Brookes University, came over. He was very upset by my question because he thought Prieto and Hall’s book was awful. He told me it was so bad that several scientists had tried to prevent Springer from printing it.
I told Raugei that I had looked very hard for any criticism of the book but had not been able to find any rebuttals, so what exactly was wrong with it? Raugei replied that the book wasn’t peer-reviewed. So I asked why someone didn’t write a paper to refute the book, and he said that since it wasn’t peer-reviewed, why bother, but I pointed out that Farrell in 2006 had used non peer-reviewed papers in his famous ethanol EROI study. I don’t know if their book not being peer-reviewed is a valid criticism or not, does anyone know?
When I asked Raugei to tell me more about what was wrong, he said that it was inconsistent in so many ways, not defensible the way economic inputs were converted from money to energy such as the insurance figures, some air travel expenses, too haphazard, inconsistent in method and goal, not clear enough in stating that this is just one snapshot moment in time in Spain and that it used an ill-advised subsidy scheme, that the EROI is not the same in other countries and parts of the world, and that the goals should have been more explicitly explained.
What goals? I assume he thinks they try to come up with low EROI figures, which is outrageous, they have no special interests in pushing the result up or down.
If anything, Prieto ought to be skewing results towards a high solar PV EROI since he built some of the solar plants he writes about in the book. He could make more money by touting solar PV rather than by criticizing it. Hall certainly has no dog in this fight. In fact, if there were a way to have outsiders with no financial interest do EROI studies I’d be all for it, because parties with a financial interest tend to skew the results, such as the National Corn Growers Association funded scientists, who found the highest EROI results in their non-peer-reviewed papers.
I know there has been a firestorm of criticism of this book, but it’s all within private email, and the only one I have been privy to said that a better LCA database should have been used.
EROI is the only rational way to look at energy contraptions and to reach the right conclusions about what should be done. I don’t have high hopes that a standardized way of doing EROI will be done.
It was ironic that Steven Chu was the opening keynote speaker at this net energy conference, since Patzek once wrote me that “Steven Chu decided not to fund my Laboratory Directed Research and Development (at Lawrence Berkeley Laboratory) project whose goal it would have been to arrive at a consistent thermodynamic description of all major energy capture schemes bio and fossil, so that we compare apples with apples. What I did not appreciate is that no one wants to know that they may be working on a senseless project, such as industrial hydrogen from algae. I despair seeing the rapid corruption and sovietization of American science (without the Soviet strengths in basic sciences), but can do little about it. … It is not easy to get funded on the subjects I have proposed. …In fact, my LDRD proposal to develop the comprehensive thermodynamic language to talk about the different energy resources was just not funded…”
Someday when a future history of science author attempts to write about the history of EROI, I hope that Patzek, Hall, and others have written memoirs that discuss how hard it was to get funding, get published (did scientists really try to prevent Spain’s solar revolution from being published?!), the criticism they received, and so on, because I think it will be of great interest to the grandchildren and further generations down the line. Understanding why renewables have such low EROI might prevent cargo-cult like behavior to spend huge amounts of resources and time to build them after the dark age that may ensue at some point on the downslope of Hubbert’s curve.

A raíz de esto y por alusiones, decidí contestar en el propio blog de Alice y en el foro de Energy Resources, adonde había saltado el debate, de la siguiente forma:

Pedro Prieto’s 4/11/15 response to criticism of his book:

Alice, as promised, let’s start answering and commenting on some of your wise comments.
The first thing is to confirm that no EROI studies can be taken seriously if the range of results varies so wildly. So it is quite a sensible approach to try to reconcile the different studies and methodologies.
Having said that, the prevailing methodology is what fails, specifically in the case of Solar PV analyses, but also in others. Experts in solar PV will have more and more available data as time passes from global installations.
Until now, we had seen many studies on different solar PV technologies with different typologies and topologies. Even before our book “ Spain’s Photovoltaic Revolution. The Energy Return on Investment” (Prieto & Hall. Springer 2013) appeared, there were already many variances and divergences.
Even works of Fthenakis or Raugei have contemplated significant variances in the EROI results over time and with different studies of solar plants.
But they all had a methodology in common: they generally used, as you have correctly pointed out, the best material recovery, the best theoretical solar PV system in each case, the best irradiated areas, the assumption that systems will operate in full along the lifetime with no problems. In summary, a methodology that has helped or served as documentary support or reference to many to reach global conclusions on the long term ability of modern renewables to replace, take over or substitute fossil fuels, from a given particular plant analysis extrapolated massively. That was the case, for instance, of Mark Jacobson and Mark Delucci in their studies on how modern renewables could replace fossils and supply the present global consumption. This is a traditional bottom-up approach.
After my experiences of several years in the field with different technologies, typologies, topologies, latitudes and state of development countries and confronting with the real world results, Charles Hall and myself, after having had a pint of beer in an Irish Pub in Cork commenting these issues, in the ASPO International Conference held there in 2007, decided to embark in a study on solar PV. But we tried to do it in a radically different form. It took us several years of back and forth, discussions, checks and double checks, consulting with other experts and so on.
The study, as many of you may already know, was on a real world installed plant in the best irradiated country in Europe (Spain), with the official and very accurate energy production records of the Ministry of Industry (read by telemetry to more than 40,000 digital sealed meters in each of the respective individual plants) over a period of three complete years (2009-2011). That was the main innovation: a top-down analysis and the huge scope of the solar PV plants working in the real world, rather than theoretical academic bottom-up approaches.
With more than 140 GW of installed plants worldwide, and several complete yearly cycles of operation of many of them, it is going to be increasingly difficult for some authors to continue with the academic approach, to verify real behavior of the EROI.
Now, about the energy input boundaries.
Of course, if we focus only on the energy inputs of the solar modules and their composition (glass, aluminum frame, connection box, copper or silver soldering, doping materials, silicon, ingots, wafers, cells, etc.) and perhaps inverters or metallic structures orienting and tilting the arrays, then we may come with spectacular results in a very good irradiated area with the theoretical module yield. This is what has been generally considered in most of the studies carried out to date and what is proposed by some authors as the recommended methodology.
But this is just one of the factors we looked into when we decided to analyze the energy inputs of a complete solar PV system, not just what appears in the marketing pictures of the solar plants.
After many years working in the field, one can appreciate the number of activities that are indispensable (sine qua non conditions), for a solar PV plant to work and operate as some of the authors of several EROI/LCA/EPBT studies consider they are going to work.
We differentiate some 24 factors and additional analysis that was not absolutely complete nor exhaustive, but proven and existing. None of these factors had been considered or hardly appeared in but few of the analyses made by the most renowned solar PV EROI authors. Your study of our book already identifies some of them and I have mentioned them on many occasions.
One of the factors, a7 (the energy input required for modules, inverters, trackers (if any) and metallic infrastructures, labor excluded), was precisely the EROI as usually calculated by many authors. We decided not to judge the different results of this universe of conclusions but to accept a sensible average of the range of many publications that gave us an EROI in itself for this concept of 8:1; that is, for 25 years of lifespan an Energy Pay Back Time (EPBT) of 3.1 years. Or an energy input cost equivalent to 0.125 of the total generation along the lifespan of the system.
But then we started to consider the rest of the factors (boundaries or extended energy input boundaries) and discovered that conventional EROI studies were ignoring 2/3 of energy inputs indispensable to get the solar PV plants in operation.
The list calculated the energy inputs, based on the experience of several plants in Spain and extrapolating to the 4 GW installed power studied in the book, to road accesses to the plants, foundations, canalizations, perimeter fences, evacuation lines, rights of way, O&M module washing or cleaning self consumption, security and surveillance, transportation — sometimes as far as from China, premature phase-out or un-amortized manufacturing and other equipment, insurances, fairs exhibitions, promotions or conferences (like the one you had in Stanford –to whom to attribute the involved energy expenses?), administration expenses, municipality taxes, duties and levies, cost of land rent or ownership, circumstantial labor (notary publics, public officers, civil servants, etc.) agent representative or market agent, equipment stealing or vandalism, communications, remote control and plant management, pre-inscription, inscription and registration bonds and fees as required by the authorities, electrical networks and power lines restructuring ass a consequence of the newly injected 4 GW in a national network with about 100 GW, in unexpected and not previously planned nodes of the grid, faulty modules, inverters or trackers, associated costs to the injection of intermittent loads: network stabilization associated costs (only referred to combined cycle gas fired plants, well known costs).
Some of these factors may certainly have diminished with time. Many others, have certainly increased over time. Taxes, for instance, have raised sharply. Stealing in Spain, for instance, is not relevant, but in many countries of the world it is a problem.
We mentioned and developed a little of the associated energy costs of the injection of intermittent loads, by pump up or other massive electric energy storage systems, because we knew it was going to be fundamental and relevant and did not want to open any more the old wounds in an already meager EROI. These costs are still today in a fierce debate in Spain and in many other countries, but they are certainly relevant, should the modern renewables have to replace the present fossil fueled global societal functions.
As you can see, the BOUNDARIES are of essence to determine the real life EROI, rather than an academic EROI. No one critical of our book, could say, to the best of my knowledge, that any of these briefly listed factors was not a real one and was not needed to have (at least in Spain) a solar PV system up and running along its lifetime. But for some strange reason they had never considered them.
Once they recognized the facts of real life, then this battlefield was rapidly abandoned and shifted to the “comparison” with other energy sources, namely the fossil fuel sources. Some authors were claiming that if fossil fuels were treated with these ‘extended’ energy input boundaries and factors, their EROIs should obviously go down in a similar proportion.
What they did, then, was to use a multiplying factor on the order of 3 for solar PV, arguing that it has a logic, when comparing equivalent systems and using an equivalent methodology. I fully disagree and I have shown in several occasions the reason why:
The world uses (mostly burns) about 13 BToe/year of primary energy or more than 510 EJ/year.
Of that, approximately 170 EJ of fossil + nuclear go to produce an equivalent of 40 EJ of clean and useful electricity, this making the point of Raugei valid to some extent, if the solar PV systems would entirely go to replace electricity produced by fossil fuels, because of the losses of about 2/3 of the primary energy in the conversion process.
But the world is not behaving in this way, as scientists like Raugei and Fthenakis must know.New renewables just enter into the energy equation to simply provide more energy to the global system.
Above all, the most important flaw in this assumption is that the world also consumes about 285 EJ in non-electrical uses, like aviation, civil works, mining, transportation, merchant fleets, armies or agriculture (eating fossil fuels, Dale Allen Pfeiffer). And it happens that if we would pretend to use electricity from renewables to replace the fossil fuels used for these global activities, likely through an energy carrier like the eternal hydrogen promise, the pretended multiplication factor used by Carbajales et. al, would immediately operate in the reverse form and become a division factor, probably in the order of 3, with respect to the direct use of fossil fuels of today. That is why we did not employ this “correction factor” used by Carbajales et al.
I will not enter into this debate further, because I find it futile. I do not care if when treating the EROI of coal, oil or gas with these extended boundaries may go down 2/3 from already published studies, now ranging with the old methodologies, for instance, from 100 to 12:1 for oil, depending on the period and places, or 60 to 20:1 or coal or gas in similar levels.
Taking down these 2/3 of present EROI studies will not change the fact that this society is now moving itself with fossils in an 80%. And makes it possible to move it. This is the final proof. And an important part of the rest (excluding perhaps a part of biomass in underdeveloped countries) is also being produced because the energy subsidies given by fossil fuels to the other sources, like nuclear, or hydro, that we could not have dreamt of having them, if a well endowed fossil fueled society and its related machinery and technology wouldn’t have been available. Nuclear, hydro, solar PV, solar thermal or wind energies are underpinned (or absolutely underpinned) by a fossil fueled society, not the vice versa. The global society has been making its growing economic, industrial and technological life basically without those energy sources. But we could not imagine these sources working and feeding themselves in all the complex value chain, and besides giving an important net energy surplus to the global society. Not now, neither in a foreseeable horizon.
That is, we can not ignore this crucial fact: biomass helped initially to coal to develop, but 60 years from the first massive use of coal, this fossil fuel had already passed biomass in volume and versatility of use and became quite independent of biomass.
This happened circa 1900, at the level of 800 MToe/year of global primary energy consumption and with about 1.6 billion inhabitants.
Then came oil, much more dense and versatile than coal. It took oil again about 60-70 years to pass coal and biomass as the main global energy source. This happened circa 1960, but then, in a consumption level of 3,000 MToe/year and with 3 billion people on Earth.
Now, we move in the level of 13,000 Mtoe/year of global primary energy consumption and with about 7.2 billion people. But gas or nuclear have not passed oil as the prime energy source. And we have to wonder why, if they were discovered and tried to be used massively more than 60 years ago.
Quite the contrary, we are moving fast, because of peak oil, back to the possibility of coal surpassing oil again in a decade or so, as the main energy contributor, but this time, probably at a lower global consumption level and probably with a world population still growing in numbers and in poverty.
The first two big energy transitions (biomass to coal and coal to oil) were made with the surpassed energy source still growing and helping to initially boost the coming one, but soon proved to be quite self sufficient to feed a growing and demanding global society, well after paying for their own energy inputs in the exploration, mining or drilling, extraction, transporting, refining and distributions processes WITHOUT ANY DOUBT, because nobody will doubt the evolution of the last century and the role of the fossil fuels on it. Now, we have to face the third big energy transition, in the highest level of energy consumption and population and with the main energy fuel, oil, in depletion.
Of course, one has to accept that in this complex world, all energy sources are somehow interrelated, but, as Orwell said in The Animal Farm, ‘all animals are equal, but some animals are more equal than others’. This is exactly what is happening with the energy sources and its properties and qualities: they can all be measured in EJ or in TWh or whatever, but some are more equal than others. Meaning that there is an obvious ASYMMETRIC interdependence of energy sources, being in the last century, the fossil fuels (and oil in a very first place), the ones responsible for our present global status.
To me, then, there is a non sequitur to shift the EROI battlefield to try to extend the boundaries in the fossil fuel EROI studies, to lower them and favor renewables by comparison, because whatever the EROI and the boundaries considered, it is obvious that the present global society spending 13 BToe/year of primary energy (80% of them from fossils), has been able in the last century (we shall see for how long) to pay their own energy expenses, and BESIDES putting a huge net energy surplus at the disposal of 7.2 billion humans and keep growing in a spectacular form for more than a century.
For instance, when the IAE mentions in their WEOs the costs of ‘subsidies’ to different energy sources, it always calculates much bigger subsidies for fossil fuels than for the modern renewables. It is a sort of energy fallacy, from my point of view.
If the global society has resources to subsidize anything, it is because it has previously gotten a surplus of resources from somewhere. And this ‘somewhere’ is obviously a global society that has created them using mainly fossil fuels at discretion. I can ‘subsidize’ my son to go to the cinema, but I cannot ‘subsidize’ myself from the salaryI earn by myself and saved in my left pocket, by changing it to my right pocket.
I understand that some fossil fueled activities may certainly be ‘subsidized’ in certain forms. For instance, kerosene for aviation in the airports, which is tax exempted in many countries, when compared with gasoline. Or ‘subsidized’ coal prices paid to depleted coal basins in Spain to continue producing low quality brown coal, to keep the social peace in the region and avoid the miners revolting. But it is a fallacy to conclude that ‘somebody’ is ‘subsidizing’ fossil fuels globally speaking, when fossil fuels are 80% of our global activities creating surplus. From a strict energy point of view, fossil fuels are subsidizing basically the whole present world activities. Period.
What in reality the OECD watchdog does is a mystifying operation. When digging up the IEA figures of ‘subsidies’ of fossil fuels, one discovers that they are really talking about ‘prices’ or ‘price levels’ of fuel in the producing countries that are selling them domestically at prices lower than those the IEA drawn line would wish they had, to leave more ground to the big OECD importers to buy this fuel from producers at prices OECD can afford.
Coming back to the energy input expenses in extended boundaries, we also left out the financial costs, despite knowing that they were quite large and generally also a sine qua non factor. Most of the plants have been financed in an 80% of the total turnkey projects at about 10 years term, with interest, that ranged from 2% to 5% per year. I firmly believe that finance is a form of using a pre-stored available resource (in a fossil fueled society, coming from fossil fuel related activities) to erect or put in place and operate a given system. In that case, an energy system. So, when one asks for credit or leasing and has to pay back with this resource the principal and the interest to the bank, in let’s say a 10 year term, this is energy evaporating into the system through the bank.
Labor energy input costs were also left aside, even we had a very good set of data from industry in Spain, classified by categories, skills and full time and part time employees in the sector. The reason was that some of our factors may have had already included part of this labor in, to avoid some limited duplicities.
If we had included these financial (even just the additional money created and having to pay back in the form of interests by the requested credits or leasing) and labor energy input cost, the solar PV EROI would have probably plummeted to <1:1.
In fact, it is very surprising how they criticize the methodology we used to evaluate the financial data (which they did not question basically in numbers), by stating that the conversion of monetary into energy units is not adequate and do not conform to conventional input-output methodologies. Our methodology is clear in these conversion units and reflects a quite direct relation between GDP and total primary energy spent in Spain or between active labor and energy spent per laborer or any given and specific related industrial activity or service rendered. This despite we mentioned that Spain hasn’t publish, for years, any input-output tables for the economy (Carpintero, Oscar).
However, it seems remarkable how some are incapable of detecting any anomaly in describing EPBT’s of solar systems recovering the energy spent in them in a question of few months for a life time of 30 years (EROI’s of 40:1 !!) and the astounding divorce with the economic reality, of a world or promoters that look for about 10 years economic recovery, this including heavy premium tariffs (Germany, Spain, Italy, now UK or France) or tax holidays or exemption (US and others) or economic recoveries that last more than the expected life time, if no economic incentives are given.
Without these incentives, the rest of the world is a renewables wasteland. Promoters are virtually not investing (with few exceptions in volume worldwide) in modern renewables, if there are no such incentives. The 140 GW world installed base so certifies, with about 70% of the global installed base made in developed countries with incentive schemes and some 25% made by emerging countries, like China or India (now Brazil or South Africa in a much lesser amounts), also with strong political incentives to cope world markets, leaving a meager 5% for the rest of the world. Doesn’t this crude reality shows anything in their conversion of monetary units to energy units methodologies, to the ones giving EPBTs of few months and financial recoveries of many years?
So, I am not surprised, Alice, that some experts, having in their records tens of papers published with high solar PV EROI results, would have shown some annoyance at your question on our book. I would humbly ask from here that when somebody mentions that we work with some methodological ‘inconsistencies’, -a term to which they are so fond of to disqualify other disturbing views- they should rather look into the above explanations and facts of the real world.
I have kept silent until now on what I consider a very regrettable behavior now made public by Raugei, as per your comments. It is true that they dared to write our publisher asking him to stop publishing the book when it was in a draft version in a sort of censorship I had not seen since several centuries in medieval Spain. The recommendation came after somebody took the draft from our publisher without our consent some time before the release and they tried to stop the publication, even threatening that they would discredit it, as they have been doing since it was published, if it were published. I have never seen such a type of behavior, even less in the academic instances.
The reason they gave first is that we missed our final EROI (2-3:1 being quite conservative and I reaffirm myself more and more as years are passing) by an order of 3. That was precisely the Raugei view on the penalty to be imposed on fossil fuels, if a clean electricity source could replace every kWh of fossil fuel origin, considering that in conventional fossil fuel (or nuclear plants for the case) we need about 3 units of primary energy to get out 1 unit of electric energy. We tried to clarify this in some posts, but unsuccessfully.
Fortunately, the publisher did not consider this a direct threat and the book was finally published.
As for the Raugei comment that the book was ‘awful’ because it had not been ‘peer reviewed’, he qualifies himself. Just look at the acknowledgements of the book. Two professors in Physics from different universities did review the book and produce sensible comments. Charles Hall, the coauthor, is an institution in EROI, that is here questioned with superficial comments. Besides, I understand that publishing a book is a free decision, that does not necessarily require peer revisions, yet despite that, we did have our work reviewed. Perhaps what Raugei wanted to say is that the peer review was not made by the usual reviewers in an endogamis game.
I have been observing that in the academic world, things are getting unfortunately tougher. Some of the technical papers have sometimes more pages of references than pages of content (see more of my comments on the article below). In the case of solar PV systems, and the references in published papers, it seems there is an excess of ‘selfies’ which were a fashion in the academic papers, much before than with the smart phones and the sticks. And secondly, it appears that credits are gained or given by the number of references that a given person is quoted and this has started a race for a sort of endogamic cross-quotations, that gives all the reason to Tadeusz Patzek, when he talks about the ‘Sovietization’ of the American science. Perhaps what disturbed Raugei about our book is that we also skipped somehow from these habits and did not leave to the usual teams a review that, with all probability, would have ended in the basket.
Of course, Raugei is right when he presumes that our case is perhaps valid for Spain and for the 4 GW installed within the period 2009-2011. Because should we had considered Germany and its public production of solar PV systems within the same period, the Energy Return in terms of MWh per MWp installed would have been less than half of those of Spain.
I am now retired and happily growing my organic farm. Not now or since 2001, when I left working for a telecom corporation, have I had any interest in discrediting or crediting solar PV systems. I am not making my life by publishing papers and trying to gain credibility on a given subject. If anything, I should have defended, as you very well stated, the solar PV systems, because I own 50 kW within a 1 MW plant that I manage and I have helped to design, develop and done some consulting (including what we call here ‘permisología’ (an intricate paperwork to get all permits and licenses to the the solar PV plants) of more than 30 MW that are working with different technologies, typologies, and topologies in different latitudes in Spain. I have also cooperated with projects in some Latin American and African countries and I have worked as director of Development of Alternative Energies for a listed Spanish company for a couple of years within the period.

Just a final nota bene, with additional comments on the paper Energy return on investment (EROI) of solar PV: an attempt at reconciliation. Michael Carbajales-Dale, Marco Raugei, Vasilis Fthenakis, Charles Banhart Journal of Latex Class Files. Volume 11 No. 4 December 2012
The title of this paper, is a supposed attempt to reconcile different views on solar PV EROI, but I have never been informed by the authors of it, even though I have the dubious honor of being cited several times in it.

I did not know that I had formed a so called “Prieto group in Madrid ”, in second place, after Fthenakis group in Brookhaven and before Weissbach group in Berlin or Brandt group in Stanford.
Also surprising is that the document is dated in December 2012 and our book was not published until the spring of 2013. Even more surprising, that the book is mentioned several times, to be criticized, but it does not appear as such (Prieto & Hall. Spain’s Photovoltaic Revolution. The energy Return on Investment”. Springer, 2013) in the bulky references, that occupy almost as much space as the article in itself. It appears, however, as some uncertain (P. Prieto and C. Hall, “Eroi of spain ’s solar electricity system,” 2012). This does not seem to be a very edifying example in referencing others.
Then, the paper comments that “an average energy payback time (EPBT) of 3 years and lifetime of 25 years are used to calculate the EROI subscript PE-eq = 8.33 value for this part of the system. No references are given for any other input data; though it appears that anecdotal worst cases of installations were generalized by the authors”.
Well, a brief look to the a7 factor (page 78) of Energy derived from Conventional Life Cycle Analysis Studies and Calculated as an Inverse Factor of EPBT”, comes out with an EROI of 8:1 for the energy content in modules, inverters, trackers and metallic infrastructure, quotes some works of Fthenakis, Alsema and Kim among others not cited, not to make too boring the EROI publications ranging around 8:1 in their conclusions and with these parameters analyzed (without extended energy input boundaries). Some more could be found in many places. In fact, these levels of EROI for solar PV were quite common in the early years of 21st century. See, for instance, Bankier and Gale in its Energy Payback of Roof Mounted Photovoltaic Cells. Energy Bulletin. June 16. 2006, where they come out with a number of EROI’s ranging from EPBT’s from 1 year (EROI 25:1) to 25 years (EROI = 1:1)

Bankier & Gale EROIs

As can be seen from the above, we were far from using as an EROI for modules+inverters, plus metallic infrastructure in a sort of anecdotal worst cases of installations generalized by the authors. On the contrary, we were more in the low estimate in years (high estimate EROI), than using worst cases.
Now, for the record, it should also be very convenient for all the prolific authors on solar PV EROI to revise the figures given in papers published several years ago, to double check how are they performing (Energy return statistics). We are very anxious and expectant to learn how it has gone with, for instance, the hybrid PV/Thermal promising analysis, or even better, the results, years after publication, of the Fresnel lenses combined with high efficiency cells in concentration mode.
I recall specifically in this respect the V.M. Fthenakis and H.C. Kim paper, titled “Life Cycle Assessment of High-Concentration PV Systems”, in which they analyzed The estimated EPBT of the Amonix 7700 PV high concentration system with Fresnel lenses in operation at Phoenix , AZ, and found 0.9 yrs for its EPBT. I wonder if they could still support this analysis, just five years after their study and how the promising system has contributed to the grid parity worldwide, considering they recovered the energy spent on it in less than one year.
Scientific authors should be more careful when accusing to others of using ‘anecdotal worst cases’, specially for the expected Energy Return along a life time, when they are probably using ‘anecdotal best cases’, instead of going on to real life 3 years cycle proven and official statistics of production for 4 GW installed park.
Talking about the life time (directly involving the Energy Return), it is very interesting to see how some papers have changed the estimated life time of solar PV Systems from 25 years to 30 years. It is curious that virtually all manufacturers give a maximum of 25 years of power guarantee of their modules (with the corresponding degradation process over the years) and 5 years of material guarantee (the later superseding or prevailing on the former in case of failure) and we find scientists happily granting 30 years for the EROI studies. In my opinion this is a clear attempt to produce higher EROI’s and lower EPBT’s with no rational grounds.
The fact that the Carbajales et al paper ends recommending “that the conventions outlined by the EIA PV Systems Program Task 12 (Environmental, Health and Safety) be followed in conducting EROI calculations, considering that the IEA methodology has easily swallowed the 30 years life time for solar PV modules, gives us a very clear clue of what is going on with these recommendations.
In our discussions on this topic a couple of years ago, an editor came to say that if our factors were really sine qua non (indispensable) for the system to be up and running and the IEA methodology did not considered them, perhaps it was the moment to change the IEA methodology.
I would just recommend the IEA tour Spain (it is not the worst country in solar PV systems; on the contrary, it is one of the most efficient in terms of MWh produced per Mw installed). The IEA should come and check and double check how many solar PV plants have not lasted, for a variety of reasons, the 25 year life time of the manufacturers or the 30 years of the IEA backed by some scientists. Just in 2015 alone about 40 MW have been dismantled, with a lifetime averaging about 5 years. Trials are the delight of reputable and expensive law firms, which earn quite a lot of money preparing lawsuits against promoters, manufacturers, banks and the government. That is real life, far beyond the academic instances. I am following now a demand of a promoter that has decided to buy 2/7 of the modules he originally bought for his 500 kW plant, because the manufacturer (not Chinese), he originally bought from 6 years ago, has disappeared, as have most of the European manufacturers in the last 5 years.One wonders what is the value of a technical guarantee on power, if the life time of the manufacturers becomes much shorter than the one of the power of the promised modules. This is, of course, ‘anecdotal’, although not for the interests of the affected promoters.
After a couple of years from the publication, I have much more data to reaffirm for myself that we were really conservative in our 2.4:1 EROI for many different reasons and factors. But I will not publish more data. I will go back now to my organic garden and wish you all the best for what I suspect may be a grim future.
I’m a pessimist because of intelligence, but an optimist because of will. Antonio Gramsci.
Pedro in Madrid, without any group.

A raíz de esto, surgieron más comentarios de diversos participantes en el debate como sigue:

Ted Trainer, un profesor de Ciencias Sociales de la Universidad de Nueva Gales del Sur, en Australia, autor, entre otros trabajos de “The Simpler Way” (el camino más sencillo) dijo:

Ted Trainer, author of “Renewable Energy Cannot Sustain a Consumer Society” and many other great books detailing what needs to be done, wrote this thoughtful response to what I wrote about the net energy conference:
Thanks Alice for your valuable comments on the EROI of P/v issue. Yes it is very disappointing that so much confusion and acrimony surrounds this crucial issue, and that they seem not to be moving to a resolution as quickly as they should be. There are of course big interests at stake, with the conventional high EROI assumption suiting the industry, and the theorists who have previously put out such claims. At the very least Prieto and Hall should be commended for getting the whole messy issue of boundaries and components, and appropriate energy cost assumptions for the various components, on the agenda. Sadly the disputation over this issue illustrates the way scientists are not immune from prejudiced and nasty behaviour, (a considerable amount of which my efforts to analyse renewables has evoked.) As Alice notes, when large scale research funding is at stake there can be strong incentive for competitors to reinforce perspectives that suit them.
As I see it the goal should not be a single EROI figure for PV, because much depends on the situation and conditions. We need values for, for instance modules operating at the average site in Spain with its level of radiation and losses, and we need figures for the various components in the system, such as energy used to produce modules in the factory, energy used to produce the factory, energy lost in inversion, in typical inefficiency due to dust, poor alignment…, and in transmission… , energy embodied in inverter replacement, energy used to get workers to the factory, energy used for O and M at the solar farm, energy “retrieved” when the modules are recycled … A fairly thorough provision of these elements would enable anyone to work out the EROI for a particular plant at a particular location, and most importantly the EROI assuming a given set of boundary assumptions. Graham Palmer has just begun a PhD at Melbourne U intended to sort all this out
I strongly object to Raugei’s comments to you re peer review. I have little respect for the entire peer review edifice, due to my unsatisfactory experience in trying to get critical analyses published. Very often I have found the comments of reviewers to range between nit picky imposition of the way they would have expressed things or gone about the job, through reasoning that I see as at least challengeable and at times dead wrong, to rejection on utterly idiotic grounds … such as being told that my recent c 20 page detailed critique of the 2014 IPCC report on renewables was “not scientific”, after waiting seven months for review. (That phrase constituted the full case given for rejection.) On another occasion, where it took over a year to get through the difficulties, I was presented with a seven page essay disagreeing with elements in my case. If that reviewer wanted to express a different view he should have done it somewhere else, not try to insist that I say what he would have said. I have another case where possibly a c 50 word review from probably the most prestigious individual in the field said the paper was good, but the paper was rejected because a second even shorter review was unfavourable. The reasons were so unintelligible that I had to ask what they meant. It eventuated that the editor said he didn’t think it was the kind of paper his journal published … after I had waited seven months.
I see the process as far too prone to the whims, prejudices and in fact arrogance of reviewers and editors. They should get out of the way and let people say what they have found or think, and focus only on things like pointing out mistakes or pointing to overlooked evidence or assumptions, or logical errors. Their role should be to help get ideas and analyses out to others, and to block only as a last resort. Too often I have found that reviewers think their role is to make authors conform to their preferred style and they assume the right to condemn work that doesn’t proceed as they would have. I have written reviews in which I say I think the argument is wrong and the procedure not satisfactory but I think the paper should be published, because I could be mistaken and the paper does present a case that it is important for us to think about.
Ultimately what matters is not whether some guru approves of your analysis, what matters is whether the case is sound/convincing/persuasive/well supported, and that judgment should be up to readers, and the quality of the work should be established over time as others in the field comment on it. My main concern here is what must be the large amount of time and good work that doesn’t get published because of the whims of some guru. I would assume that most of us have had papers rejected by one set of reviewers but regarded highly by those from another journal.
So I see any attempt to block publication of controversial, and even flimsy/challengeable cases, on grounds to do with “peer review” as very annoying. I have no interest in whether or not it was peer reviewed; what matters is whether or not the case it argues is sound, or valuable, or ought to be heard. (Theses that are dead wrong can turn out to be valuable contributions, by helping subsequent discussion to clarify an issue.)Whether or not it was peer reviewed has nothing to do with whether or not it is correct, or a valuable contribution, and, Alice, should certainly not be regarded as “a valid criticism” .
In my view Raugei raises some important problems, such as the effect on the Pietro and Hall conclusions had by the Spanish subsidy system, but it’s appropriate to now sort these, not to regard them as reasons why the gook should be rejected. The most important issue he raises is in claiming that the energy input to PV production should be reduced to one-third, on he grounds that it is electricity and PV produces electricity. As I see it this simply depends on whether the electricity used to produce the modules is coming from PV (or wind or CSP) generating systems … and at present it isn’t. In a world where all electricity came from PV farms it would make sense to put the value of the electricity input into the denominator of an EROI, but in the presenter world the energy going into production is (mostly) coal.
Endnote: This book was only available online at the University of California. It’s a shame libraries are putting many journals and books into electronic versions only. Especially this book. Microchips, motherboards, and computers will be among the first casualties of declining fossil fuels, because they have the most complex supply chains with many single points of failure, dependence on rare metals, and so on (see Peak Resources and the Preservation of Knowledge for details). I encourage you to get your (university) library to buy a hard copy of this book, so that future scientists and historians will understand why our society didn’t replace fossil fuels with “renewables” even though we knew oil couldn’t last forever.
On an energy form, Prieto recently wrote (March 2014): “Since we wrote the book, I have been able to experience a few more incidental factors: mice delightfully gnawing the cables and covers and optical fiber communication color cables, and storks excreting on modules with about 6 inches size -one cell- per excretion. Real life has many factors that they are not accounted in organized studies in labs, universities with particular technologies and plants in perfect irradiation places.”
Bankier, C.; Gale, S. Energy payback of roof mounted photovoltaic cells. The Env. Eng. 2006, 7, 11-14.
Bullis, K. 26 Aug 2010. Self-Cleaning Solar Panels A technology intended for Mars missions may find use on solar installations in the deserts on Earth. MIT Technology Review.
Colthorpe, Andy. 18 July 2013. Solar Shakeout: Spain’s Cel Celis begins insolvency proceedings PVTech.
Fthenakis, V.H.C. et al. 2011. Life cycle inventories and life cycle assessment of photovoltaic systems. International Energy US Energy Investment Agency (IEA) PVPS Task 12, Report T12-02:2011. Accessed 19 Sep 2012.
Neubacher, A. January 18, 2012. Solar Subsidy Sinkhole: Re-Evaluating Germany’s Blind Faith in the Sun. Der Spiegel.
Nikiforuk,Andrew. 1 May 2013. Solar Dreams, Spanish Realities. TheTyee.ca
Parnell, John. 22 July 2013. Spain’s government accused of killing solar market. PVtech.
Parnell, John. 23 July 2013. Spanish government facing court action over cuts to solar support. PVTech.
Raugei M., et al., “The energy return on energy investment (EROI) of photovoltaics: Methodology and comparisons with fossil fuel life cycles.” Energy Policy (2012), published on line doi:10.1016/j.enpol.2012.03.00897. See more at: http://www.todaysengineer.org/2013/Jun/book-review.asp#sthash.YsRjuI9R.dpuf
Prieto & Hall, 15 Apr 2011. How Much Net Energy does Spain’s solar PV program deliver? A Case Study. State University of New York 3rd Biophysical Economics Conference. Data sources for Energy Generated and Energy Invested slide 10, How monetary costs were converted to energy units. Slide 12, How the embodied energy costs and boundaries were determined Slides 17, and much more.
Soble, J. March 3, 2015. Japan’s Growth in Solar Power Falters as Utilities Balk. New York Times.
Spanish solar energy: A model for the future? Phys.org

El debate entonces se trasladó al foro Energy Resources, donde Alice hizo comentarios sobre el mismo y Marco Raugei, también por alusiones escribió el pasado 13 de abril de 2015:

I find it rather unfortunate that my personal comments to Ms. Friedemann about the book by Prieto and Hall were misconstrued as stemming from the frustration at a failed attempt at “medieval censorship”.
To try and clarify once again:
the main issue with Prieto and Hall’s book, apart from the somewhat crude nature of their money-to-energy conversions, is that their analysis was promoted and advertised as reporting on “the true EROI of PV” (largely understood as that of the technology itself, to be then liberally compared to that of “oil” or “coal” as alternative energy sources),
instead of something like “the societal EROI of PV in Spain, in the specific circumstances dictated by the incentives and deployment schemes in place that country in 2009-11, and including all the documented (yet often in principle avoidable) system-level inefficiencies, as well as a host of monetary inputs used to indirectly support the PV industry in its early stages of expansion, etc. etc.”.
As to Mr. Prieto’s response of 11 April, I have no problem in conceding that there is some truth in many of the points he makes.
However, the main issue there is, again, that of a loose definition of goal and scope.
In fact, by reading through his long post, it appears that Mr. Prieto’s ultimate interest lies not in comparing PVs to e.g. coal- or oil-fired electricity production systems, but instead in comparing the ability of PV to completely replace fossil fuels by single-handedly supporting all of society’s energy demands.
I personally wonder whether it is even reasonable to frame the problem in these terms – but even if one were to accept this as the starting point for one’s analysis, the fact remains that one would then have to be extremely cautious in the way the latter is carried out and advertised, in order to:
(i) avoid a somewhat random (and hence yes, inconsistent) cherry-picking of the energy inputs, and, even more importantly,
(ii) prevent the subsequent inadvertent (or even worse, intentional) extrapolation of the results to a different context from the one for which they were intended.

El 14 de abril de 2015, Charles Hall también intervino brevemente y publicó a través de Alice el siguiente texto en Energy Resources:

Charles Hall says:

April 13, 2015

There are many things I could say, but mostly hooray to Alice for bringing this up again in her marvelous fashion! And to Pedro for his exhaustive replies, many of which show how conservative our initial assessments were. Of course our analyses were for one country at one time. OK lets see such an empirical study done elsewhere and with boundaries that include ALL the necessary inputs. The reader should know that both Weissbach and Graham Palmer have published studies that are comprehensive and give results similar to ours.
One thing I find amazing is that no one mentions the sensitivity analysis Pedro and I did in chapter 7. This covers the special effects of the Spanish situation, weighting electricity vs fossil energy, removing financial services from the assessment or considering an energy assessment of labor. None of them, other than the obvious effect of multiplying the electrical output by three or including the energy to support labor’s paycheck, made any very large difference in the EROI. There are other sensitivity analyses here and there in the book. Why in the world do people criticize us for things we had already examined and published the effect of? Did they read the book?
The boundaries issue remains critical and I for one will not believe any EROI that does not have something like as thorough as we have attempted in our book. All that we do is enormously subsidized by fossil fuels, and we need to understand that better. I hope that we will someday have abetter estimate of the energy cost of indirect costs, business expenses, roads etc. but leaving them out completely is, in my opinion, a greater error than using a value that has uncertainty, especially when that uncertainty is examined. In the 1970s we had some fair idea of the energy costs of all kinds of goods and services in society due to the wonderful work of Bullard, Hannon and Herendeen using detailed I-O tables and good government data, with uncertainty analysis. Services were quite energy intensive, although not as much per dollar as most goods. Now there are no such analyses and government energy use data sources degrade year by year. So we used and corrected these old values and compared and corrected them against what we could come up with for these issues today. All explained in the book.
Most of the uncertainties in EROI are greatly reduced when goals and boundaries are consistent, when an explicit methodology is used (e.g. Murphy et al. 2011, Order from Chaos, a preliminary protocol…in Sustainability) and when real data, not cherry picked lab data, is used. I look forward to better science in the future, but the failure of the Stanford meeting to answer Alice’s spot on question, and the ascendency of neoclassic economics vs using as hard real science as we can bring to bear, does not leave me with too much hope.

De aquí, un lector trasladó este debate a otro foro especializado en energía (peakoildiscussion), donde Ron Swenson, Director del International Institute of Sustainable Transportation y de una decena de empresas y entidades más relacionadas con la energía solar y miembro de ASPO USA, hizo el siguiente aporte el 17 de abril de 2015:

I’m afraid this remains a narrowly framed discussion. If you want to moan and groan about solar EROI, then you might consider at least one more piece of the puzzle…

Because it can’t be replaced, the EROI of oil is eventually going to be <<1 of course. (It won't pay energetically to pump it out of the ground or squeeze it out of tar sands.) Our children's children will have to bring it up from below using old prairie windmills I suppose.

In the meantime while it still flows out of the ground, the EROI for oil is not all that pretty either, because there's more to it than just extraction. Here for example is an illustration from one of Charlie Hall's publications:

20150419 Ron Figure 1

Once the oil becomes «Consumer Ready Fuel» then this is what happens (per RMI)

20150419 Ron figure 2-

13% of 20.5% above = 2.7%.

Then take note that the 13% efficient engine is moving mostly metal. If several humans in a car constitute even 10% of the vehicle’s mass, then the oil-based transportation system is 2.7% * 10% = 0.27% efficient carrying people (the real point, after all).

No, mine is not a complete analysis either, but it serves to point out that the solar folks aren’t the only ones whose analysis is incomplete.

As Pedro and Charlie know, I didn’t object to the book being published, but I did find errors in an early draft that had subsequently been corrected. I also experienced blatant censorship of my own work when I found dramatic errors in the EROI analysis of a solar system by our common hero Howard Odum 10+ years ago when he was still amongst us. It goes both ways.

We have a long way to go. Getting funding for resolving these crucial questions is the key. Using economics (an instrument of policy, not a science) is where humanity is really off the mark. (Any lousy technology can be gamed for a while but then the chickens come home to roost.)

How about if we take a good hard look at this as a community and find common ground for a better conversation … and work as a community to find resources? (We peaksters are not _that_ pathetic!)

Pitting solar against oil against cold fusion is not the point. The point is to establish common terminology, identify boundaries (as suggested) and include the complete life cycle, plus factor in the plight of our children’s children. Climate change comes to mind for some of us. What’s the EROI of oil and coal if the result is inundated coastal cities? How much energy from whatever source will it take to pump the oceans out of human settlements?

Best regards,

Ron Swenson

Antonio Turiel, suficientemente conocido en este blog, contestó a Ron Swenson el mismo día de la siguiente forma:

Interesting remarks, Ron. My feeling is that the situation regarding the EROEI of oil is even more convoluted.

For instance, looking at the first figure, we see several industrial activities (extraction, refining, transportation…) where part of the energy of oil is «wasted», but I think that the picture is more complicated than that. That «wasted energy» is in fact used for feeding the own industrial process in some sense, this generates some (typically well-paid) jobs and estimulates activity (that is what energy is useful for). My point is that a part of that «wasted energy» is in fact used in the more complex Human ecosystem which goes beyond the final consumer. Maybe the final consumer just gets 20% of oil energy, but a significant part of the other 80% keeps the wheel spinning (for instance, some «waste heat» at refineries is used for other chemical processes that provides us useful chemicals and plastics). So a clear definition of «wasted energy» is in order.

Regarding the second figure, there is also some subtleties here. We tend to oversimplify the discussion on energy because going into the details is very complicated. From the perspective of the end user, it is irrelevant the amount of energy that s/he is provided but the useful energy (or even rather, the «usefulness») s/he can get from it. A person who drives a car doesn’t want to know how many megajoules of fuel have been loaded into, but how many miles s/he can drive. It is irrelevant if a quite large part of the energy is wasted as far as the deal makes sense for the driver (i.e., the amount paid per mile). And thus, at the end, the question is what we want the energy for, in the first place. Energy is just a mean, not a goal on itself. Any process in which energy is employed has its inefficiencies, but this is already somehow implicit and embedded in our calculations. It doesn’t really make a lot of sense, for instance, to compare the efficency of an electric car in terms of how it uses the energy once loaded into if we dismiss all the losses of the process of charging the battery, including the embedded energy in all the parts of the car. My feeling is that, yes, most likely just a small fraction of the original energy goes into doing «useful work» (exergy, if you like) for any process you dare to think about, but the losses are always there and are going to be always the biggest part because that’s the way Nature works. All the discussion about «wasted energy» recalls me the discussions more than a decade ago about the «waste DNA» that constitutes 99% of our genome; it finally came out that that «waste DNA» was in fact important.

Another important point is that EROEI calculations are static, that is, they assume a stationary society. This is no longer the case. We can well be wasting previous stored energy (in the form of key assets and infrastructures that we are no longer maintaining, and thus they are lending us their embedded energy until they finally break up) just to keep oil being pumped/extracted/synthetised from the most inefficient sources. This use of our previous «energy savings» may lead us to the wrong impression that everything is fine and that the EROEI is ok. We need rather a definition of dynamic EROEI, which in particular would help us to identify energy sinks that are actually draining our immobilized «energy savings».

So, if we want to clarify the situation from an academic perspective I feel that probably those three issues should be analyzed. From my personal point of view all that is however quite irrelevant, because as we keep on discussing about those challenging, technical issues, real-life first-hand experience shows us that something is going deeply wrong in our society and that the long promised energy saviors are never arriving. Maybe we should rather be preparing ourselves for the next hit.


Ese mismo día también intervino el profesor Ugo Bardi, titular del Departamento de Ciencias de la Tierra y miembro de ASPO Italia, de la siguiente guisa:

Calculations are never perfectly right. Sometimes, they can be perfectly wrong but, normally, they are useful if you know their limits. But they are not useful when they are used to bolster one’s ideological prejudices.

On this point, I am always amazed by the true hatred that some people have against renewables and photovoltaic in particular. Just yesterday I had a taste of this on the «peak oil» group on facebook. (https://www.facebook.com/photo.php?fbid=379559368743674&set=gm.10150667093274858&type=1&theater)

As Ron correctly points out, «we peaksters are not that pathetic». And we should not be. I understand that some people took the idea of «peak oil» as meaning that we will all return to the stone age. So much that they WANT to return to the stone age and react emotionally to any hint that we might, after all, mitigate the decline, at least a bit. It is the exactly opposite attitude to that of those who cover their ears with their hands when they hear the fateful «peak» term and then run away singing «la-la-la» to themselves.

Well, I guess it is the way humans are.


Sam Carmalt, presidente de SW Consulting SA en la Universidad de Yale y consultor energético, comentó en el mismo medio y día:

Two points:
1) I find the EROEI concept extremely useful. But whether it can be used quantitatively at the precision needed to make investment or policy decisions is more of an open question. At present such decisions are made primarily by considering the monetary return on investment — which has its own major problems with subsidies, taxation and so forth. If the economy is indeed powered by energy (note particularly the economic publications by Georgescu-Roegen, Beinhocker, and Charlie Hall in collaboration with Kent Klitgaard in this regard) then in theory it seems to me that the two ROIs should align. And I might note that parliaments cannot repeal fundamental economic laws, although they often try.
2) Attempting to suppress any thoughtfully presented and rationally supported position is not the way to move forward. This is especially important to remember when the position is not the consensus view. I recall that Lord Kelvin opposed Darwin’s theory of evolution; similarly, it took an Australian medical doctor years to get his theory that stomach ulcers are caused by bacteria rather than gastric secretions past the peer review objections that simply reflected accepted belief.

También consideré necesario volver a responder a Ron Swenson (en el pasado debatimos esto con intensidad y frecuencia, al parecer con las divergencias todavía vigentes) de la siguiente forma y en el mismo medio:

I will start agreeing with Ron that EROI of fossil fuels will finally go to <<1:1. This gives also ground to Antonio comments that EROI is a dynamic (and very complex today) process. Although it was not so dynamic when we were in the stage of hunter gatherers for the two previous million years.

However, much before we reach <>1:1 in ground 1 level of pears to pears comparison, without any deep study. And if in this common level or ground 1, modern renewables appear to have much less EROI than fossil fuels and result, after more than 60 or even 100 years of having been invented, are still totally underpinned in the fossil fuels society, then Houston, we have a problem.

And now, let’s go to ground zero if, for instance, we want to introduce climate change and try to calculate the equivalent energy input expenses of this certainly extended boundary into the equation (or energy needed for corrections that climate change will require thereof, if they can be solved by pouring more energy into the system). In this case, probably by now, you all may have reached to the conclusion that it probably the experiment of the last 150 years of growth based on fossil fuels and that our grand grandparents was not worth the effort and that we should have rather given up extracting what it should have been always left underground.

And from here, to the obvious conclusion: should we had no reached to this level of technological advances, social benefits and present worldwide infrastructures, heavy machinery fleets, etc. and with them the level of complexity, all of them thanks to the abundance and versatility of fossil fuels, we could not even dream of having modern solar or wind systems (or also nuclear, for the case) up and running.

I cannot imagine gallium arsenide vaporization chambers, micrometric filters, mining of the variety of sophisticated materials required in modern renewables (copper, indium, titanium, neodymium, praseodymium, aluminum, tempered glass, special saws to cut ingots in micrometer slices, doping systems, modern transport, packaging, pick ups for maintenance, etc., without this society that is obviously changing the climate. What a paradox, isn’t it?

Of course, I encourage Ron or everybody to continue searching and finding energy resources to keep this 150 years game or illusion going on for some more decades, but trying to avoid, as much as it is possible to fool oneself playing solitaire and comparing pears with pears, as much as it is possible in this complex society, working in the same ground levels when analyzing or compare different energy systems.

In my case, after many years of this search, I have concluded that fossil fuels were a poisoned gift and I could not find in all these years any other energy source with the same abundance, versatility and availability, until now (of course it will end and sooner than many expect). So, my obsessions to continue the way we were, have finished.

I now am trying to rewind in my memory and learn from my grandmother way of living and her energy habits in a village, with a very good and sustainable use of solar and wind energy. Warming herself in the sunny days of winter by sitting with her neighbors looking south, protected from the cold winds of the north by the sun dried brick’s wall while either weaving, sewing, mending, patching or embroidering, or in winter in the patio in the shadow, with a small well and the walls and floor full of flowerpots and fruit trees. Using wind to dry the washed cloths; animal dung to fertilize the farm and very little wood to cook the delicious and simple meals. Reducing its mobility to a much less than one kilometer in 99% of the movements and so forth. It was not romantic; it was very tough and hard living; but it was way more sustainable than what we have today. And over all, she had the dignity in her humility that I miss today in many people living in our arrogant modern cities with a lot of material comfort and enjoying absurd mobilities as if there were no tomorrow.



Ron Swenson volvió a contestar de la siguiente forma el mismo día:


Thanks for your kind words in respect to your grandmother and your thoughtful comments.

On 4/17/15 2:45 AM, Pedro Prieto wrote:

> I have concluded that fossil fuels were a poisoned gift
Well put. FWIW, in Swedish, the word gift actually means poison. (It also means married… that’s another, longer story.)

We are yet to discern the true meaning of these words. In that light, I’m having a little trouble with your comment:

> I could not find in all these years any other energy source with the same abundance, versatility and availability
«Abundance, versatility and availability» come with a price if it doesn’t happen to be «abundant» or «available» underfoot but must instead be [essentially] stolen [sold at a price far below its intrinsic value] from other parts of the world:
20150419 Ron figure 3 text 2

I wonder if there is a connection between that «red ink» and this red ink:

«The Great Recession in Spain began in 2008 during the world financial crisis of 2007–08. In 2012 it made Spain a late participant in the European sovereign debt crisis when the country was unable to bailout its financial sector and had to apply for a €100 billion rescue package provided by the European Stability Mechanism (ESM)….»


The game keeps rolling along because the incumbents (those who control the deal flow) can always extract a percentage from the flow and then pass on their costs to an evermore impoverished constituency.

Is this abundance or debt bondage? I’m reminded of a song from my youth, Tennessee Ernie Ford singing a coal miner’s lament, «I owe my soul to the company store.»http://en.wikipedia.org/wiki/Sixteen_Tons


PS: Spain is not the exception. My own native USA is by far the more egregious player in this drama.

Gerry Agnew, escribió en Energy Resources el 16 de abril de 2017

That is some article Alice!

So, two questions if I may-

1) With solar power proven to be just about everything it was NOT supposed to be, can we say that the abandonment of DESERTEC a couple of years ago shows that even with an environment which has to be about as favourable as possible (the Sahara), solar couldn’t make a go of it? Remarkable! Is there any environment were it CAN work, or is it a terrible financial gaffe which is going to see write-downs/write-offs on an immense scale?

2) So, without generous subsidies, is solar a mirage – it can never work? Are solar companies a terrific short sell in other words (to bring this back to something I am quite familiar with)?

Have you done any work with wind power? Is this a similar boondoggle?


A lo que Alice contestó:


The EROI of solar PV is probably negative, at best very low, wind isn’t great either. Although I think EROI is the only way to rationally analyze what contraptions might work or not, that is best left to the experts in the field.

Another way of looking at wind and solar is that they simply add to the blaze of the age of oil but won’t outlive it because they don’t produce enough energy to reproduce themselves AND have extra energy to keep civilization going.

It’s easier to understand why they’re useless when you consider that FREIGHT transportation depends on oil. There is nothing in your house you paid for that didn’t get there on a truck, and most likely on a ship as well. If we can’t electrify trucks, and the lifespan of highways is about 20 years, electricity won’t matter. Rail can be electrified, but the tracks go very few places. In America, Canada, Mexico this isn’t likely to happen – one electric locomotive equals about 2200 PHEV cars, so charging up 25,000 locomotives is a like charging 55,000,000 autos (if battery operated), or if overhead catenary you’d need about 250 new power plants. Our existing locomotives are often over 400,000 pounds, the railcars over 300,000 pounds, and so a LOT of power is needed. Europe has much lighter trains and equipment.

Even if we could electrify – diesel engines can last 40 years – we won’t have the TIME or energy to replace trillions of dollars of equipment AND build an electric distribution system.

On top of that, it isn’t clear that we can balance over 50% intermittent electricity (or even over 33%) without energy storage which is not possible to the extent needed, or a national grid – that’s not going to happen, and that takes decades as well.

I don’t see a solution, but even if I were a techno-optimist I don’t see any way around hard times because it would take decades to build something else with less and less fossil fuel — my guess is that people would rather eat than build windmills with the remaining petroleum.


También, Vasilis Fthenakis, profesor de la Universidad de Stanford, puso su comentario en Energy Resources a través de Alice como sigue:

I don’t have the time to go over the details of the editorial above so I will limit my response to three basic items:

1. My name (Vasilis Fthenakis) was cited above as having published estimates or EPBT and EROEI based on models, not actual data and that my estimates include only modules, not the rest of the system. Alice, you got it completely wrong; if you bother to look at my peer-reviewed journal articles (and Yes I believe in peer-review) you will see that my estimates (also consensus estimates from IEA PVPS Task 12 comprising LCA analysts from 12 countries and 2 industry associations) are all based on actual process data; data that originate in 13 different manufacturing facilities in the EU and the US and were cross-referenced and verified exhaustibly.

2. It is true that we describe, quantitatively in great detail, the best actual systems of which there are min-to-min and hourly performance data over many years and we don’t bother with the worst. We do this because only the best survive, and yesterday’s best is proven to be today’s average. All the ground-mount utility PV systems in the US that were constructed since 2010 and are being operated accordingly. The fact that the system prices for c-Si and CdTe PV fixed tilt and 1-axis tracking have gone down a factor of 3 since the timing of Pietro’s experiences is a clear indication of the continuing evolution taking place which we have been accurately described and quantified.

3. I also thought that presenting Pietro’s book as a book describing the global PV reality was a disservice and for the two years before the publication of the book I tried to engage the authors asking for their data which they were not providing. And yes I complained to the publisher about this lack of scrutiny to literarily promoting one’s view as the view for the world and hinder the growth of solar. Vasilis Fthenakis, PhD, senior chemical engineer (with tenure) Brookhaven National Laboratory and professor of earth and environmental engineering, Columbia University author or co-author of 300 articles and 4 books on topics at the interface of energy and the environment (email: vmf@…)

I want to add to the 1st item above that our estimates of EPBT (and by extension EROEI) are based on energy and material burdens in the life-cycle of the modules, mounting structures, inverters, transformers, cables, thus of the whole system till the high-voltage feed into the substation. All based on actual-process data. To the reader: if you have the time and the interest please read our publications; some of them have been cited 300 times in journal articles of others -they must be credible cheers, Vasilis Fthenakis

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  1. Interesantes disgresiones sobre el tema de la TRE de la fotovoltáica.


    No hace falta que nadie me revise esta realidad.

    Y la demostración de la inminencia del Colapso, tampoco necesita ser revisada: la realidad se encargará de hacerlo a la vuelta del próximo decenio.

    La única alternativa es la de construir «botes salvavidas» colectivos en nuestros valles, en nuestros pueblos, y abandonar lo más rápidamente que podáis las grandes ciudades, y los actuales modos de vida.

    Y aún así y todo, tampoco garantizaremos la supervivencia de nuestr@s niet@s.

    Un abrazo, Pedro,


  2. Dubitador dice:

    La conclusion es que no solo no va a aparecer una energia que sustituya la actualmente utilizada sino que no debe aparecer, pues no debe mantenerse este modo de vida, ha de cambiarse, ha de sustituirse por otro, por uno compatible con los recursos y energia que se puedan obtener del medio entorno sin desestabilizarlo, incluso dedicando sustanciales esfuerzos a reparar lo desbaratado y colaborar con el medio.

  3. Dario Ruarte dice:

    Jo jo jo!. Claro, que exista un libro que fundamenta de un modo tan detallado los inputs que llevan a establecer una TRE en un rango de 3 para la fotovoltaica es como un suicidio anticipado para la burbuja de renovables.
    Tengo la sensación que, en algún momento del futuro cercano el libro de Hall y Pedro va a «desaparecer» de los anaqueles. 🙂

    O, como pasa en las leyendas urbanas de los inventos de combustibles mágicos en los que siempre la ‘industria del petróleo’ compra las ‘patentes’ o silencia de algún modo a los inventores, en este caso cabría esperar que la industria fotovoltaica compre a los autores quienes, a cambio de irse a vivir a una isla paradisíaca con muchos millones, publicarán su retractación en un opúsculo titulado: «Nos equivocamos. La TRE de la fv era como de 20 o 30» 🙂

    En fin Maestro Prieto. Te has ganado una dura lucha y una posición atacable por haberte tomado el trabajo de desmitificar los rendimientos de una industria que está presta a dar su salto en «inversiones» y necesita formar la masa crítica de aplaudidores y «expertos» recomendando sus virtudes para poder movilizar los millones de los inversores. Tú te lo has buscado !

    Pero, como siempre, consigues el maravilloso efecto de ponerlos a todos a revisar las cuentas y a toser disimuladamente cuando surgen las preguntas «molestas» porque «… según dice Pedro Prieto en su libro…».

    Haremos lo posible para facilitarte la tarea… y seguir generando «toses incómodas» entre los vendedores de crecepelos. No generaremos más energía pero, al menos vamos a divertirnos con los debates. 😉

  4. The traditional energy pollution environment, so the photovoltaic industry has been advocated. But in the acquisition of traditional energy at the same time, can also extract a variety of industrial raw materials, which is necessary for modern industry. Without oil and coal, many of your things will disappear, such as cars, plastic products and so on. vu sand making system So the traditional energy access is inevitable, that is, oil, coal is necessary to be mined.

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