Cassandra has moved. Ugo Bardi publishes now on a new site called "The Seneca Effect."

Friday, May 15, 2020

The Great EROEI Scam: Are renewables a good idea?

The cheetah in the figure knows very well that it cannot spend more energy in chasing the impala than the impala can provide once eaten (in other words, the cheetah needs an energy return on the investment (EROEI) >1). Carnivores make no calculations about that question, they only know that, if they want to survive, they have to run. And this is our destiny, too. If we want to survive, we need energy and we need to move away from fossil fuels before depletion or climate change (or both) destroy us. But, unlike lions and cheetahs, we tend to discuss a lot on the subject and, sometimes, to get it wrong. This is the problem with the recent movie "Planet of the Humans" and its wrong evaluation of renewable energy (image by Nick Farnhill, creative commons license)

Years ago, when I discovered the concept of "EROEI" (or EROI), energy return for energy invested, I was both delighted and elated. "Here is," I thought, "an objective way to evaluate and compare the efficiency of energy technologies. No more shaky financial calculations, no more ideology, no more politics, only facts. And everyone has to agree on the facts." And the beauty of the concept was that if the EROEI is smaller than one for a certain technology, then it is an energy sink, not an energy production system.

I was wrong more than I could have imagined. From when the idea of EROEI was first proposed, in the 1980s by Charles Hall, the concept was stretched, squashed, squeezed, twisted, and shaken until it became a useless mongrel. Ideology took over from physics and EROEI became a support for preconceived ideas rather than an evaluation tool.

I should have known better, but I hadn't realized how difficult it is for most people, including opinion leaders, to think in terms of data. One of the problems with EROEI is that many people just can't understand it, but the main one is that it is not easy to quantify its value. You can say, "this apple is red" just by looking at it, but not "this plant has an EROEI of 12.5." That is unless you perform a complex calculation based on the rules of LCA (life cycle analysis). Impossible if you are not trained in this specific field of work.

In practice, it is not difficult to find people with sufficient knowledge of the rules to be able to bend them in such a way to obtain the results they (or their sponsors) want. The result is a jungle: for every conceivable energy technology, you can find a range of values of the EROEIs so large that you can pick one according to what you like (2+2=5).

But it is not so much a question of cheating, it is just that science and politics talk two different languages. If you are a scientist, you reason in terms of data and models. If you are like most people, you reason in narrative terms. And narrative, as we all know, is all about a conflict between bad guys and good guys. So, that's the way people tend to evaluate the EROEI issue: they judge the messenger rather than the message. And they tend to like messengers who bring them messages they like. It is called "selective exposure" or "confirmation bias."

That's the reason for the success of a movie such as "Planet of the Humans." It is a clever movie because it passes a simple message that resonates with many people in the environmentalist movement: "big capital bad." That may even be true: there are plenty of scams embedded in concepts such as "green growth." But, in the movie, the real target is not big, bad capitalism, but renewable energy. It is presented as being unable to support itself because it has EROEI<1  or that, at least, the value of the EROEI is too small to support a complex civilization.

Then, most environmentalists know nearly nothing about the most elementary technologies of communication and many of them reacted by criticizing the many factual errors of the movie. But they didn't realize that most people are unable to evaluate the details of the takedown of the movie that many experts engaged in. And the result was a remarkable success for the movie and for its sponsors.

In any case, you can't change the way people think, not in a short time at least. So, my personal opinion is that it is useless to engage in infinite discussions about the EROEI of renewables or of other technology. And it is especially useless to discuss at length about a bad movie such as "Planet of the Humans." The human mind is such that it can demonstrate just about anything on the basis of apparently logical arguments. You probably know the story of how in 1903 the American physicist Simon Newcomb "demonstrated" on the basis of physics that human-made machines couldn't fly -- that was just five years before the first flight of the Wright brothers.

I am sure that with a little work it would be possible to "demonstrate" on the basis of physical principles that cheetahs cannot catch impalas. But cheetahs don't need theories telling them that they cannot feed on impalas. They run and they catch their prey. So, we can demonstrate that renewables work by installing renewable energy plants, as many as possible. And show that they work -- they do produce energy. And the more plants we install, the better the world will be for us and for those who'll come after us. It will help climate to stabilize, too. 

On this matter, below you may read a post that I wrote three years ago. See also a post I published in 2016: But what's the REAL energy return of photovoltaic energy?

Why EROEI matters: the role of net energy in the survival of civilization 

Published on Cassandra's Legacy, March 13,, 2017  (slightly modified in this version of May 15, 2020)

The image above was shown by Charlie Hall in a recent presentation that he gave in Princeton. It seems logical that the more net energy is available for a civilization, the more that civilization can do. Say, build cathedrals, create art, explore space, and more. But what's needed, exactly, for a civilization to exist? Maybe very high values of the EROEI (energy return on energy invested) are not necessary.

A lively debate is ongoing on what should be the minimum energy return for energy invested (EROEI) in order to sustain a civilization. Clearly, one always wants the best returns for one's investments. And, of course, investing in something that provides a return smaller than the investment is a bad idea. So, a civilization grows and prospers on the net energy it receives, that is the energy produced minus the energy required to sustain production. The question is whether the transition from fossil fuels to renewables could provide enough energy to keep civilization alive in a form not too different from the present one.

It is often said that the prosperity of our society is the result of the high EROEI of crude oil as it was in the mid 20th century. Values as high as 100 are often cited, but these are probably widely off the mark. The data reported in a 2014 study by Dave Murphy indicate that the average EROEI of crude oil worldwide could have been around 35 in the past, declining to around 20 at present. Dale et al. estimate (2011) that the average EROEI of crude oil could have been, at most, around 45 in the 1960s Data for the US production indicate an EROEI around 20 in the 1950s; down to about 10 today.

We see that the EROEI of oil is not easy to estimate but we can say at least two things: 1) our civilization was built on an energy source with an EROEI around 30-40. 2) the EROEI of oil has been going down, owing to the depletion of the most profitable (high EROEI) wells. Today, we may be producing crude oil at EROEIs between 10 and 20 on the average, and the net energy yield keeps going down.

Let's move to renewables. Here, the debate often becomes dominated by emotional or political factors that seem to bring people to try to disparage renewables as much as possible. Some evidently wrong assessments claim EROEIs smaller than one for the most promising renewable technology, photovoltaics (PV). In other cases, the game consists of enlarging the boundaries of the calculation, adding costs not directly related to the exploitation of the resource. That's why we should compare what's comparable; that is, use the same rules for evaluating the EROEI of fossil fuels and of renewable energy. If we do that, we find that, for instance, photovoltaics has an EROEI around 10. Wind energy does better than that, with an average EROEI around 20. Not bad, but not as large as crude oil in the good old days.

Now, for the mother of all questions: on the basis of these data, can renewables replace the increasing energy-expensive oil and sustain civilization? Here, we venture into a difficult field: what do we mean exactly as a "civilization"? What kind of civilization? Could it build cathedrals? Would it include driving SUVs? How about plane trips to Hawaii?

Here, some people are very pessimistic and not just about SUVs and plane trips. On the basis of the fact that the EROEI of renewables is smaller than that of crude oil, considering also the expense of the infrastructure needed to adapt our society to the kind of energy produced by renewables, they conclude that "renewables cannot sustain a civilization that can sustain renewables." (a little like Groucho Marx's joke, "I wouldn't want to belong to a club that accepts people like me as members.").

Maybe, but I beg to differ. Let me explain with an example. Suppose, just for the sake of argument, that the energy source that powers society has an EROEI equal to 2. You would think that this is an abysmally low value and that it couldn't support anything more than a society of mountain shepherds, or not even that. But think about what an EROEI of 2 implies: for each energy-producing plant in operation there must be a second one of the same size that only produces the energy that will be used to replace both plants after that they have gone through their lifetime. And the energy produced by the first plant is net energy fully available to society for all the needed uses, including cathedrals if needed. Now, consider a power source that has an EROEI= infinity; then you don't need the second plant or, if you have it, you can make twice as many cathedrals. In the end, the difference between two and infinity in terms of the investments necessary to maintain the energy-producing system is only a factor of two.

It is like that: the EROEI is a strongly non-linear measurement. You can see that in the well-known diagram below (here in a simplified version, some people trace a vertical line in the graph indicating the "minimum EROEI needed for civilization", which I think is unjustified)):

You see that oil, wind, coal, and solar are all in the same range. As long as the EROEI is higher than about 5-10, the energy return is reasonably good, at most you have to re-invest 10%-20% of the production to keep the system going. It is only when the EROEI becomes smaller than ca. 2 that things become awkward. So, it doesn't seem to be so difficult to support a complex civilization with the technologies we have. Maybe trips to Hawaii and SUVs wouldn't be included in a PV-based society, but about art, science, health care, and the like, well, what's the problem?

Actually, there is a problem. It has to do with growth. Let me go back to the example I made before, that of a hypothetical energy technology that has an EROEI = 2. If this energy return is calculated over a lifetime of 25 years, it means that the best that can be done in terms of growth is to double the number of plants over 25 years, a yearly growth rate of less than 3%. And that in the hypothesis that all the energy produced by the plants would go to make more plants which, of course, makes no sense. If we assume that, say, 10% of the energy produced is invested in new plants then, with EROEI=2, growth can be at most of the order of 0.3%. Even with an EROEI =10, we can't reasonably expect renewables to push their own growth at rates higher than 1%-2%(*). Things were different in the good old days, up to about 1970, when, with an EROEI around 40, crude oil production grew at a yearly rate of 7%. It seemed normal, at that time, but it was the result of very special conditions.

Our society is fixated on growth and people seem to be unable to conceive that it could be otherwise. But it is clear that renewables, with the present values of the EROEI, cannot support a fast-growing society. But is that a bad thing? I wouldn't say so. We have grown enough with crude oil, actually way too much. Slowing down, and even going back a little, can only improve the situation.

(*) The present problem is not to keep the unsustainable growth rates that society is accustomed to. It is how to grow renewable energy fast enough to replace fossil fuels before depletion or climate change (or both) destroy us. This is a difficult but not impossible task. The current fraction of energy produced by wind and solar combined is less than 2% of the final consumption (see p. 28 of the REN21 report), so we need a yearly growth of more than 10% to replace fossils by 2050. Right now, both solar and wind are growing at more than a 20% yearly rate, but this high rate is obtained using energy from fossil fuels. The calculations indicate that it is possible to keep these growth rates while gradually phasing out fossil fuels by 2050, as described in a 2016 paper by Sgouridis, Bardi, and Csala


  1. ok about the need for the growth, but beyond real systemic accounting still needed, EROEI it should be necessary but not sufficient. what about systemic impacts on ecosystems and on mineral and other natural elements supporting life ?

  2. Two of my concerns with renewables are founded upon the narratives that have been used by the industry and its supporters to market them. First is the idea renewables allow us to continue our complex society as is with little transitory disruption or contraction of energy use. Your discussion of EROEI should dispel such notions but they persist, with almost religious adherence. A second is the language used: 'clean' and 'green'. Renewables are neither green nor clean; they not only require vast quantities of fossil fuels for their creation but use ecologically-destructive processes in both their upstream and downstream avenues of production, maintenance, and disposal.
    It seems to me that unless or until we abandon our pursuit of the infinite growth chalice, we are destined to experience the collapse that always accompanies overshoot.

  3. Thanks for this timely article Ugo. I particularly like the insights on growth. People often do not understood that even a small growth like 3% results in an exponential increase. With the current world population we need negative growth.
    Also, if we leave fossil fuels in the ground, then that is a future emergency energy source that we can draw on in case of disasters such as massive volcanic eruptions and meteorite strikes.

  4. The connection between EROEI and economic growth was a really nice idea that I havent seen discussed before.

  5. "And it is especially useless to discuss at length about a bad movie such as "Planet of the Humans." You won't convince anyone using facts. Instead, a practical demonstration that renewables can work, just like cheetahs and lions can demonstrate that can catch impalas. "

    If just that was enough....
    There are already hundreds of GW of PV and wind plants in the world that have proven their efficiency in supplying energy to entire nations and decreasing their emissions, without particular environmental impacts.
    Yet in the film they are not worthy of a glance by instead making cherry picking of a few old plants, poorly designed, harmful and failed.
    So even the evidence is not enough to defeat bad faith.

    Furthermore, the continuation of the effort towards the transition to renewables, being uncomfortable and expensive, requires both the consent of politics and public opinion. And I do not see how else to convince both that that film is crap, if not to point out its factual errors, distortions and lies.
    Of course if Michael Moore change it mind, and make another doc on the same subject more objective and updated, it would be great, but in the absence of this, to point to the abysmal quality of the only one he, and Gibbs, did, is the only way we have.

    Finally, I would like to point out another psychological effect at the basis of the success of the film (I don't know if it has a codified name): we love to see the "unstained and fearless heroes" fall from the pedestal and be soiled, We admire them, but evidently, under below, we also hate, hoping that one day they will prove mediocre and fallible like us.
    So the fact that the film defames some relevant characters from the "green" world, and in general those wise environmentalists, always ready to scold everyone for what they do, with their fingers raised, presenting them as foolish (or paid) servants of capital , I think it pleased many, and not only those who were already prejudiced against them.

  6. Ugo, another great read. I'm sorry you mentioned Simon Newcomb: when he published his "proof" Alberto Santos Dumont had been merrily flying above the rooftops of Paris for four years. All scientists are partly ignorant; the good ones know where the boundary between knowledge and ignorance lies. Michael Moore, I fear, does not, which is why his movie is polemic, not science. But to this extent I believe he is right: the "green" movement has been hijacked by big business, and perverted into a money making scheme that will do very little to save the planet, and a whole lot to enrich themselves.

    On my own behalf, I am opposed to our current incarnation of wind energy. I have some scientific reasons, but also a wholly unscientific one. These windmills are placed to catch the prevailing winds; most of these are also pathways for migrating birds; and to put these lethal machines in their path is surely a crime against Nature.

    Your thoughts on EROEI are also timely, but here I would like to sound a note of caution. Many calculations I have seen about green enrgy greatly underestimate the EI. The energy required to mine and refine rare earths, to clean up the immense amounts of pollution those mines generate, somehow gets minimised. And for solar panels, the energy required to clean up the pollution that they themselves slowly leach into the environment. Growing up in tropical Africa, I became a firm believer in "low tech" green; the current fervour for "hi tech" green is, I suspect, another dead end of our technological hubris.

    But keep up the good work, and thank you again for your unique insights.

  7. The growth is fundamental feature of Western civilization. There is no Western civilization without growth. The growth is the most important value that Western civilization promotes. That is the fundamental problem of the Western civilization - what else is it offering as the substitute for growth? What other value is it promoting? None at all, because Western civilization is basically materialistic in nature. It can not offer anything else except growth. That's why the whole project of Western civilization is doomed. If a civilization is unable to offer relevant human motivation it will fail even if it's EROEI is 100! A civilization able to survive must be able to offer motivation narrative to citizens. In the case of Western civilization, without growth such motivation will be lost and the whole structure will crumble.

  8. I have been watching the numbers for years now. At one point I was very optimistic about renewables but then very skeptical. I am now in acceptance of their limited value and their vitality to a transformation in decline. I reject the hype of them being a transcendental energy paradigm. The primary problem is all the other issues of the human and planetary condition. There is not enough power in renewables to overcome this. Human behavior is possibly the biggest issue. Lower populations of awakened humans who can live with seasonality, intermittency, and less material in localized living would be a start but even now not enough to transcend the consequences of planetary and human decline. Failure is baked into the cake so live with it. It is only accepting this paradigm of decline can one go forth and use renewables rationally.

    Renewables are a great tech. I spent $20K on mine. I am also using the old fashion renewables of wood, grass, and animals. It is a mix of modern and old that can transform life. That said what I am doing since it is also green does not pay the bills of modern life. I am using my fossil fuel drenched nest egg from a previous life to do what I am doing. If SHTF I am in a good place at least for the start of it. My local in the Ozarks of Missouri is not bad in regards to resilience and sustainability but still not survivable in a really bad situation. I am better than a mega city of 15MIL but less good than maybe somewhere in the southern hemisphere with good land and less people. My point is I have renewables but it will only improve me so much. I then have the issue with all the other obstacles.

    Energy can only solve so many problems and this is where the techno optimist veers of course. Tech leads them by the nose instead of starting with a wisdom that choses what tech to use and what to reject. Cost and price do the leading now instead of values. The math is not there in my opinion for a transition paradigm but a transformation is definitely there. Many people have money now but instead of buying a basic solar system for more resilience they buy a fancy car or boat. Cities buy a new sport stadium. Nations a new aircraft carrier. The complexity of all these complications clouds true value that I feel green prepping unlocks. Green prepping says do some renewables but also do some old ones with some new ones. All this glitter and dopamine of this tech crap is a siren song of doom. Where renewables could be truly helpful, they are instead in risk of being stranded assets when applied in efficiency of cost and performance in huge applications. That said the world is going off the cliff of sustainability so I guess a huge solar farm is better than a Permian basin. But it still is wrong way in regards to humanity and the planet.

  9. renewables are a parachute at most.

  10. Ugo: You know, this sort of analysis/experiment might well be done on an individual scale. I took the liberty of linking to this post and writing one of my daily rambles using you as a starting point. I have hopes that this will pan out. Since we aren't doing that well applying EROEI an a societal basis, maybe one can use it as an "ideological lens" to view one's own life.

    Due to the current situation (the virus that dare not speak its name) all of us are doing a re-evaluation of our lives. This might serve us well as one of the approaches to view the problem with in order to come up with valid individual strategies.

    Thanks again for the good work


  11. Have you read how "renewables" are produced?
    It takes a huge amount of energy from fossil resources to produce them, "renewables" do not have either the energy output & unlike fossil RESOURCES produce NO raw materials.

    "Renewables" cannot grow our food, they produce no fertilizers, agricultural chemicals, their output is too weak & their life span is of course limited as are the RESOURCES needed to build them.
    As oil declines, our ability to mine,transport & fabricate raw materials into the components that make up "renewables", their production will decline along with oil & without enough OIL, most of us won't be EATING.
    We foolishly fed our growth on a temporary resource & as that declines, so will we.

    1. Sheila, have you noticed that with this comment you are validating my point? That is, you are arguing by using all caps instead of data.

    2. Sheila, what do you mean with "fossil fuel can grow food"?
      That fossil fuels produce nitrogen fertilizer (surely not phosphate and potassa, which come from mines...)?
      But to produce nitrogen based fertilizer you need hydrogen and nitrogen. The second one come from air and the first one can come from fossil methane, but also from water electrolysis, that can be done with renewable electricity or concentrated sun heat.
      Moreover organic fertilizer can came from compost of organic waste or their anerobic digestion, surely not from fossil fuels.
      So also renewable energy and practice can produce "our food".

      Using organic raw material and renewable energy, you can also produce any kind of organic compound: plastic, paints, pesticides, glue, drugs, fuels, whatever you want. If we did them mostly with fossil fuels, it is just because they are cheap and all the chemical industry is been built around them.
      But there are not physical laws preventing us to use more sustainable ways in their production, we can did them if we want.
      Moreover, if oil and natural gas, are so precious to make complex chemical products, it is even more stupid to burn the 96% of them to produce banal heat and electricity, don't you believe?

    3. "Renewables" cannot grow our food, they produce no fertilizers, agricultural chemicals, their output is too weak & their life span is of course limited as are the RESOURCES needed to build them."

      Well, since with enough electricity you can do anything fossil fuels can do then they are theoretically kw=kw but the real world introduces affordability that represents survivability at some point? Enough windmills can create oil and gas like fuels. Windmills can make water happen. They can light the greenhouse too. The existential answer is likely no because no energy source likely including fusion can power a system of perpetual growth. EROI is only a hint becuase other mechanisms distort the true picture like financialization. The physics of scale are at work with the number of renewables gathering devices needed. The storage and grid enhancements needed show the true cost of renewables vastly understated. It is increasingly the case fossil fuels are unaffordable to power modern life of growth so both energy sources points to a collpase process. Either the system changes or collpase comes eventually. System change is a behavioral step with tech following. Tech cannot fix this situation instead it creates more of a problem with tech leading behavior. It is likely behavior can’t change either and that is why we are in a trap of many traps. The most apparent ones are the carbon trap and the financialization trap. These are path dependencies. They got us to where we are at but cannot get us any further. A new path means collpase.

    4. renewables can't sustain more than two billion humans.

    5. I am sure you have data and models proving your statement about the "two billion humans" -- am I right?

    6. Yes, such data is available online - however their results vary, most think we could support anywhere from 2 billion to 4 billion humans without oil.

      Of course we have millions of years of being fed without oil but then there were only a few hundred million humans on the planet.
      When we reached 1 billion around 1800, we had reached the limits of what could be supported without fossil resource inputs, the Europeans then discovered the energy & raw materials in fossil resources starting with coal & population growth speeded up with the advances in our technology in using coal, oil then natural gas.
      There are many more links.

      Now at 7.78 BILLION we have changed the very composition of our atmosphere, we occupy over 90% of the fertile land, our water is polluted as is our air, our food is now laced with toxic chemicals, we are causing what scientist call the "6th great extinction" as hundreds of living things go EXTINCT EACH DAY.
      As an example of this, I HAD swallows breeding in my nest boxes for many years, until about 6 years ago, since then they have been unable to breed due to a lack of INSECTS. Now they have failed to return, their headed for extinction like so many other living things have before them.
      I now have no BATS, No SWALLOWS, no Kingfishers,no herons, few gulls, no seabirds off the coast here.

      Sure we could stuff more humans onto this poor overpopulated planet & kill off the rest of the wild but then what?
      We will still collapse & our world will be left empty of other living things except a few surviving humans, perhaps.
      We need a viable ecosystem that includes other living things, who want's to live out their "life" in a overcrowded, dirty, stinking cement cage which is what our cities have become.
      I would rather be COMPOST!

  12. What do the companies who sell renewables say about their products, like the evaluation of everything else it seems fair to look at the marketing and judge the product against that.
    For me Planet of the Humans asked the question, do renewables and green technology live up to their own marketing. It was not a debate about EROI.

  13. Unfortunately, I think the problem with renewables goes beyond a poor EROEI. Most renewables depend on not only the fossil energy to produce the infrastructure, but the manufacure of said infrastructure (wind turbines and solar panels) itself exists as a tiny fraction of the overall world economy. The renewables industries are imbedded in the far larger economy, and when declines in fossil fuel production start forcing the simplification and contraction of the overall economy, the renewables will themselves decline. A depressed economy at some point won't be able to continue mining rare earth or other elements when the process involves extracting a ton of ore to get an ounce of the substance being sought. Processing the silicon to the 99+% purity level as solar panels require will be problematic.

    I think some renewables will be feasable on a localized scale. 125 years ago, a farmer would have to give over around a quarter of his acreage to growing hay or oats to feed the horses used to pull his farm machinery. I could see the farmer of the future dedicating a quarter of his space to soybeans or switchgrass or whatever, and having a crude still to “refine” this crop to a biofuel for his tractor. A mill-wheel by a river is also doable. But large-scale wind and solar don't seem feasable in an economy that lacks a cheap and dense energy source such as fossil fuels. Part of the problem with renewables is that they don't seem to scale up well.

    Antoinetta III

    1. Dear Antoinetta, you too are making a comment that proves my point: For most people, including you, narrative prevails over data.

    2. Wind and sun energy look like they can scale up very well

  14. Yes, the cheetah isn't concerned if the numbers say it cannot do what it does. If something can be done when the numbers say it cannot, the numbers are wrong. So if you are sure something like current civilization can be run on sun and wind, then lets see it happen. It is definitely not being done right now. All you are doing right now is giving out your own story about it.

    1. You are wrong. My point is exactly the opposite: I am citing data and facts, others are telling their stories.

    2. You have data and facts from working systems? People are using pv and wind to build more pv and wind generators from the ground up, are making agricultural and transportation equipment and running it on pv and wind, are successfully feeding people, making clothes and housing for them with this energy? Are fixing old and failing infrastructure made with fossil fuel? Are planning to expand and do this for more and more people around the world?

      The fossil fuel industry at the start didn't spend decades of argument that it was feasible to use fossil fuel to do these kinds of things. Step by step, they simply did it. All I've seen for decades is talk about how pv and wind can replace fossil fuel, and I haven't seen it happening. I don't see you arguing from the standpoint of a healthy, successful cheetah, you are arguing from the standpoint of a sick kitten-current pv and wind industry- in danger of being abandoned by its sick mother- current fossil fuel industry. You are telling us it isn't weak and sick, it isn't dependent on the failing fossil fuel industry for its weak and sick existence, but that it can do what its mother used to do when it was young and strong and you have data and facts to back this up. That is an interesting claim, but where is this working system located?

    3. Let me repeat: you totally misunderstand the issue. For a car to be a viable product, it doesn't have to be able to get "pregnant" and deliver another car. What you need is a car factory, and a car factory is not a car. The same for renewable energy. You don't need a factory powered by locally available renewable power to demonstrate that renewable energy is a viable product.

    4. Where the pv and wind generators are, as well as storage, matter because distance increases transmission costs and that affects EROEI. I am not seeing any evidence of it working. Storage systems on the needed scale aren't being built- the projected energy cost is huge. Many existing power lines have maintenance needs that haven't been kept up with, never mind building new ones. You also need to do things like make cement and steel and glass with electricity- there are technical problems with that. There was an MIT professor who worked on making steel with electricity, got a system to work on a small scale, but it uses very large amounts of electricity, and no one in the steel business was interested. And that is only part of the problem, you can't have a rolling mill running on intermittent energy, for example.
      I do need to see problems of energy storage and making and forming of basic materials solved to think this will work. I don't see it being done.

  15. The Princess and the Pea "The Princess and the Pea" A fairy tale by Hans Christian Andersen about a young woman whose royal identity is established by a test of her sensitivity.

    I'm not going to say I did not have any issues with the movie but it says some important things that people need to think about. The fact is, people don't think about the issues the move talks about now. I have known for years people need to change the ways they live and what they value if humanity will have a future. The movie while not perfect does touch on forbidden topics.

    Too many people and too much consumption. We need to admit that and realizing that is madness to burn down forests to keep lights on helps. A few lights that perhaps should not be on in the first place might be turned off.

    Having said that it is not the sole responsibility of the consumer who should be trying harder not to consume true enough; to worry about these things. Doing the right thing should be easy to do but without movies like this? How do all of us find out what is in the best of us.

    The environmental movement in America sold out. It was co-opted in America by the well to do for their purposes.

    EROEI is an important concept but it is not a holy grail and if it is twenty or more it is pretty much all the same. You pointed that out with your two to one example. It makes me think the Egyptian Pharaohs liked that theirs was low. If you have a Tiger in your tank some do not care where it came from or how low the EROEI was on its production.

  16. I should have included this in my comment. Below I quote myself which is weird, but I quote my own website for a very good reason. The quoted text is below a link to an hour long interview that Derrick Jensen had with Jeff Gibbs who directed, and produced Planet of the Humans. It has only just been posted.

    The link to the Derrick Jensen interview is below the actual movie 'Planet of the Humans' which I have featured for a week.

    Derricks' interview is a very good listen.

    "This bonus material is essentially audio only. An excellent interview with Jeff Gibbs by Derrick Jensen. The interview here amplifies the sentiments I share with Derrick. We do not hate humans. We hate what many humans do. We dislike people who only seek to only follow others and who do not think about their impact on the earth. Nazis in any form are not our friends. That is not the same as misanthropy. We respect those who honor all life and not just human life. This is a very good listen."

  17. EROEI is invaluable as a concept and tool of analysis. The devil is in the details, as they say. Let's not throw the baby out with the bath water.

    1. Yes, I think EROEI is a valuable relationship to understand. What I feel is left out is that it is important to compare energy of the same quality. Hall's original observation was about food energy, for example. Food energy can have different quality- it might be high in calories and low in vitamins and minerals and protein needed to use that energy in the body. It won't do what is needed by the body if these other factors are too low or missing. In a similar way, comparing the intermittent, variable amount energy of solar and wind devices, with the on demand energy from fossil fuel used to make the device, is comparing two very different kinds of energy quality, as if they were the same. They won't do the same things and should not be compared as if they can.

    2. And that's, of course, the large and mostly unrecognized advantage of renewable energy: it provides the highest quality energy we have, pure electric power. In a comparison with fossils, the EROEI for the latter should be slashed down by a factor of about three, to account for the unavoidable thermodynamic losses you encounter when converting hydrocarbons into usable energy.

    3. Well, no, my point was that it isn't high quality simply because it is electricity. It is intermittent and variable power electricity, and you can't use it like that for a lot of industrial processes, as well as residential needs. The amount can not only vary during the day or week, but you can have a lot of sun in the summer and very little during the winter. Wind can also be seasonal. As I mentioned above, there are serious problems in using electricity even when it is high quality for some industrial processes. Plus you not only need to generate the current amount, but far more to do these other things.
      I mentioned the problem of making steel, and just remembered that something had been done on that, using hydrogen to run furnaces. That is interesting, but the problems of making and storing hydrogen on large scales are well known and those need to be solved before using hydrogen like that is practical.

  18. That pyramid with arts at the top is ridiculous, art existed in every human society

    1. totally agree. It is an adaptation of the Maslow pyramid... and intent to attach Western positivism (facts and numbers...) to humans' needs

  19. I'm becoming skeptical about the need of growing, not only as a requisite for sustainability but just as a capitalist premise.

    There is monetary inflation... but discounting that, western nations are close or already with flat energy per capita consumption.

    Population grows yet, but projections are to shrinking if you discount population migration. Only Africa and Middle East have birth ratios that are not clear about population stabilization.

    So after population stabilization and energy per capita constant, the consumption of resources should become flat, and shrinking if you optimize the recycling of raw materials.

  20. ok... all very well known stuff in fields like Ecological Economics and political ecology... so what? why and how Moore's documentary is so bad? you don't tell us!
    the documentary simply claims, in a quite clumsy way I must admit, that renewable energy maybe are not able to deliver what many of their supporters promise. As simple as it is... and this is true. You too Ugo say that a world fully powered with renewable will be a 'slower' world. And I'm totally convinced we need a slower world... but I don't get your hostile reaction against the documentary and why you use the EROI to dismiss it. The uncomfortable assumption behind the film is that the society as it is now can't exist without fossil fuel; and a transition to a renewables powered economy must imply a radical reorganisation of social order. You often fail to analyse this point. It's not just a matter of EROI, not just a matter of facts and numbers or feasibly of technological paths.
    Of course, you can answer than I'm following narratives and not facts... but this is a very poor communication strategy I'm afraid. After all, as Kuhn has brilliantly shown, science is a magnificent 'narrative' too. The important is not to turn it into a religion like sometime you seem to do. Although I'm firmly convinced that facts exist, social science teaches us that we can't simply separate them from politics, power, and mental frames... not even super scientists like you can.

    1. You understood nothing of what I said and you attribute to me concepts that I never said -- to say nothing about your cheap insult at me, defined as a "super scientist" -- do you think you are funny?

  21. Good morning Ugo, thanks for all good work you are offering to us. How ENROI is calculated. The PV or the wind when are turned on are producing electricity. The oil has to be found, bumped from deeper and deeper reservoirs, shipped from the Guelph to Canada requires 10% of the shipment, refined and the produce electricity. What is the final ENROI. Further to that. At this point of time close to Cyprus are gathered all the warships, USA, China, Russia, Italy, France, Turkey. Israel, Egypt, Greece... guarding the "fields", is that "energy" used in calculated the fossil fuel ENROI?

    1. Good point, Chrysostomos. If you factor in 11 carrier strike groups, the EROI of oil takes a big dip!

    2. Thanks, not to mention global worming and/or 400.000 premature deaths in EU, due to air pollution, mainly frof fossil fuels.



Ugo Bardi is a member of the Club of Rome, faculty member of the University of Florence, and the author of "Extracted" (Chelsea Green 2014), "The Seneca Effect" (Springer 2017), and Before the Collapse (Springer 2019)