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ERoEI is unimportant and is being used incorrectly

In this article I will show that ERoEI is almost totally unimportant by itself. It does not matter if ERoEI is increasing or decreasing. ERoEI provides no guidance about which sources of energy we should pursue, nor does it offer any guidance about how much net energy will be available to us in the future. By itself, ERoEI is a useless figure. Although different sources of energy (such as coal or solar PV) have different ERoEI ratios, this means nothing important.
What is important to civilization (and to us) is the amount of net energy obtained from a source of energy, not its ERoEI. The two are not the same. It is the amount of net energy which determines how much we can drive, whether we can take long airplane trips, and so on.
Unfortunately, the amount of net energy from a source cannot be determined from its ERoEI. ERoEI is a ratio, so it contains no information about the amount of energy invested or returned. As a result, ERoEI cannot be used by itself to determine how much net energy will be produced by any type of energy (such as coal).
The equation for determining net energy would be as follows, given ERoEI and an energy investment:

energy_net = (1-1/ERoEI) * energy_investment

You will notice that it’s IMPOSSIBLE to solve this equation without knowing what the energy investment is. As a result, it’s impossible to calculate net energy returned from any type of energy (for example, coal) by knowing its ERoEI alone. As a result, ERoEI is a useless figure by itself and cannot be used to determine the amount of net energy which could be obtained from any type of energy, and it’s the amount of net energy which is important, not ERoEI.
Let me provide a more concrete example. Suppose you have a solar PV panel with an ERoEI of 2 which returns 1KW on average continuously for 30 years. In that case, the net energy provided by that solar panel is 131.4 MWh ((1*24*365*30)/2) over its lifetime. If, however you have 10 such solar panels, then the net energy returned is 1314 MWh—ten times the amount of net energy returned, despite no change in ERoEI. In this obvious case, ERoEI has NO CORRELATION with the AMOUNT of net energy obtained.
As another example, assume two kinds of solar panels. One kind of solar panels has a very low ERoEI of 2, and another kind has a very high ERoEI of 1,000. However, the solar panels with the very low ERoEI require 1/1,000,000th the labor to construct, and labor is the scarce factor determining how many we can build. They are identical in all other regards. In this case, it can be shown that the low-ERoEI type of solar panels will obtain over 500,000 times more NET energy despite a 99.8% reduction in ERoEI. (The total net energy returned by 1,000,000 low-ERoEI solar panels will be 500,000, whereas the total net energy returned by the 1 high-ERoEI solar panel will be 0.999). Again, there is no correlation between ERoEI and net energy obtained.
As a result, the ERoEI of solar panels is useless information by itself. You must also know HOW MANY solar panels (or windmills, etc) there are (or will be), to determine the net energy available to civilization. ERoEI cannot tell you that.
For the most part, the net energy obtained from solar power would be determined by the number of solar panels built, not by their ERoEI. In turn, the number of solar panels which can be built, is determined by non-energy factors like capital and labor, because those are the scarce factors which prevent the construction of more solar panels. This point is complicated and requires further elaboration, so I will discuss it in a subsequent article. Suffice it to say, that the net energy of solar power is determined by non-energy factors such as capital and labor, and has almost no relation to ERoEI, because the number of solar panels built is determined by the scarce factors such as capital and labor.
Generally speaking, the amount of net energy goes up as ERoEI declines, although it’s a weak correlation. This is because the amount of gross energy is vastly higher at lower ERoEI ratios, and the greater amount of gross energy more than compensates for any decline in ERoEI. For example, it’s commonly claimed that crude oil had an ERoEI of 100 in 1930, but only has an ERoEI of 15 now. I seriously doubt that, but I’ll assume it’s true for the moment. From those figures, we can show that a decline in ERoEI led to a large increase in net energy. If oil had an ERoEI of 100 in 1930, and 5 million bbls per day were extracted back then (source: ), then the total amount of net energy per day from oil in 1930 was 4.95 million bbls of oil. On the other hand, if oil has an ERoEI of only 15 now, and we extract 90 million bbs per day, the total net energy from oil per day is now 83.99 million barrels. The amount of net energy from oil is 17 times higher today than in 1930 despite an 85% decline in ERoEI. This is frequently the case; more NET energy is frequently available at lower ERoEI ratios, because the amount is so much greater that ERoEI makes little difference.
In general, renewable sources of power can provide vastly greater net energy regardless of their ERoEI. This is because they are available in far greater amounts, by a degree which totally erases the importance of ERoEI. For example, what is the maximum amount of net energy which could be provided by solar power? The ERoEI is not important except as an intermediate figure when calculating the amount of NET energy.
 
The Earth is bombarded by 23,000 terawatt-years/year of solar radiation. Let’s assume that only 1% of this could ever be captured by solar PV panels. Also assume the panels have an extremely low ERoEI of 4. In that case, the amount of NET energy which is available from solar PV is 172.5 terawatt-years/year, which is more than 10x worldwide energy consumption at present (more than 30x if you apply an energy quality correction). As a result, the amount of net energy possible is vastly greater from solar power than from fossil fuels, EVEN IF the ERoEI of solar were very low. The reason we don’t obtain that much net energy from solar panels is because we don’t have enough NON-energy resources such as labor and capital to build that many solar panels. It has nothing to do with ERoEI. Even if the ERoEI of solar PV increased to infinity, it would make little difference to the amount of net energy obtained.
Again: net energy available is a function of BOTH EROEI AND AMOUNT. Either one of them by itself cannot be used to calculate net energy. If we wish to use a “rule of thumb”, then we should assume that MORE net energy is available at lower ERoEI ratios, but the correlation is so weak that it can’t be relied upon.
Unfortunately, ERoEI theorists do not realize any of this. Over and over again, they assume that ERoEI is somehow proportional to net energy. They assume that a higher ERoEI somehow implies more net energy. This is a severe mathematical error, but it’s repeated endlessly throughout the ERoEI literature.
Let me provide some examples which I read just a few days ago:

“Look [at a] Cheetah… That beautiful and ultra efficient machine, needs an EROI of about 3:1 (sped three times less energy running for the prey, that the energy contained in the prey it is going to eat). That’s a metabolic minimum EROI for mammals.Being the minimum EROI for any live being (mammals in particular) 2-3:1 in average, to be kept alive as species and for the couple to successfully breed their offspring (minimum of 2-3 per couple), probably Charles Hall is very right to state that a minimum EROI of 5:1 is required to have a minimum (very primitive and elemental) of civilization, beyond us living as naked apes.”

No, because that is confusing an ERoEI with an AMOUNT of net energy. Dr Hall observes that civilization requires more net energy than just the metabolism of its inhabitants require. Then he wrongly concludes that a higher ERoEI means more net energy. That is a basic mathematical error; frequently, using a lower ERoEI source of energy will obtain more net energy than a higher ERoEI one.
The Cheetah example is also mistaken in other ways. The Cheetah doesn’t just have a low ERoEI; it also has TOO FEW prey which it can consume. If the Cheetah could eat prey every 5 minutes, then it would have a vast excess of energy even at an ERoEI of 1.5. The problem is that many animals eat only once per day and some animals (such as crocodiles) eat only once per week or so. If they eat only 10,000 kilocalories per week, then increasing the ERoEI wouldn’t matter much (even increasing ERoEI to infinity in this case would only gain the animal another 3,300 kilocalories). What would help is to catch MORE prey.

We can take our ERoEI 20 FF and invest them in ERoEI 50 sources and make a huge energy profit. Or we can invest them in <5 and make a loss. Our policy makers have lost their heads electing to promote loss making activities.”

No, because that is confusing ERoEI with an AMOUNT of net energy. If an ERoEI were an amount, then spending fossil fuels with ERoEI 20 on solar panels with ERoEI 5, would imply a loss of 15. However, you cannot subtract the ERoEIs of different sources of energy, because they are not AMOUNTS which can subtracted.
If you take ERoEI 20 fossil fuels, and invest them in ERoEI 5 solar PV, then the aggregate ERoEI is 100 (invest 1 unit of fossil fuels initially, obtain 20 units of fossil fuels with ERoEI of 20 thereby, invest each of those 20 units in solar panels with ERoEI 5, then obtain 100 units at the end of it for an initial investment of 1).

IMO, the only thing that could delay the bad impacts of declining high ERoEI FF is to introduce to the global energy mix an energy source that has higher ERoEI than the fuels they have to replace.Introducing low ERoEI energy sources simply makes things worse.”

No, because (again) that is confusing ERoEI with an AMOUNT of net energy. The “bad impacts” are caused by TOO LITTLE net energy, not a low ERoEI. Adding any source of energy with an ERoEI higher than 1 increases the total amount of net energy available. Only an ERoEI lower than 1 would make things worse. If the source of energy is cheaper per unit of net energy (as solar power actually is) then it is easier to obtain more net energy that way, regardless of its ERoEI.
 
…All three of the above quotations are taken from leading figures in the ERoEI literature. Granted, the ERoEI movement is a tiny fringe movement, but these people are among the leading figures of it. Over and over again, they wrongly assume that ERoEI and net energy are somehow proportional, and that higher ERoEI implies more net energy. That is a basic mathematical error. Frequently, the opposite is the case.

 

What matters is the AMOUNT of net energy available to civilization, and that amount is far higher for renewables than for any other source, regardless of ERoEI.

bountifulenergy.blogspot.com



65 Comments on "ERoEI is unimportant and is being used incorrectly"

  1. TomWayburn on Fri, 18th Sep 2020 9:03 pm 

    It may be that the total amount of net energy that can be harvested is more important than ERoEI, provided ERoEI* > 1.0; however, if ERoEI* 1.0. There is a rather long section on sustainability and ERoEI* at https://www.dematerialism.net/ . More at https://eroei.blogspot.com .

  2. bochen777 on Fri, 18th Sep 2020 9:10 pm 

    First we lost our hero Kobe in the beginning of this year, later we lost our King of Wakanda, now we have lost the Honorable Mrs Ginsburg, what is going on? What will become of this once great nation?

  3. TomWayburn on Fri, 18th Sep 2020 9:24 pm 

    It may be that ERoEI is not as important as the total amount of net energy, provided ERoEI is greater or equal to 1.0. If ERoEI* 1.0. There is a rather long section on Sustainability at https://www.dematerialism.net/ and more at https://eroei.blogspot.com/

  4. TomWayburn on Fri, 18th Sep 2020 9:29 pm 

    It may be that ERoEI is not as important as the total amount of net energy, provided ERoEI is greater or equal to 1.0. If ERoEI* less than 1.0 for an alternative energy technology, the technology does not harvest energy renewably, which shows the importance of using my methodology to compute ERoEI*. Moreover, I am under the impression that now, in 2020, we do not have a commercial solar or wind installation with ERoEI* greater than 1.0. There is a rather long section on Sustainability at https://www.dematerialism.net/ and more at https://eroei.blogspot.com/

  5. Cloggie on Sat, 19th Sep 2020 9:32 am 

    “Moreover, I am under the impression that now, in 2020, we do not have a commercial solar or wind installation with ERoEI* greater than 1.0.“

    I’m under the impression I’m Napoleon.

    Seriously:

    https://deepresource.wordpress.com/2017/12/16/siemens-reports-eroi-onshore-wind-of-50-or-larger/

    “Siemens Reports EROI Onshore Wind of 50 or Larger“

    https://deepresource.wordpress.com/2017/08/05/solar-eroi/

    “Solar EROI“

  6. Cloggie on Sat, 19th Sep 2020 4:33 pm 

    I’m under the impression I know what I am talking about.

    Fixed. Sorry for the error.

  7. makati1 on Sat, 19th Sep 2020 6:34 pm 

    Keep dreaming of that techie heaven where all your techie dreams come true, Cloggie.

    https://sunweber.blogspot.com/2011/12/machines-making-machines-making.html

    Sorry, but the real world is killing your dreams, even if you will never admit it. Dream on!

  8. Anonymouse on Sat, 19th Sep 2020 7:31 pm 

    I dont think jews believe in a ‘heaven’ strictly speaking mak do they? With cloggjude, his fascination with ‘tech’ is more of a fetish if anything. Although, I will admit, it moves back and forth between religious proselytizing the great singularity to come, (TBA) to , basic garden variety tech fetishism, then back again.

    Funny, you mention sunwebs blog. Do you know one time I pointed out wind turbines are not sentient, self-assembling entities to the cloggecolon here, and you know that Yidiot did?

    He linked to Sunwebs blog as if he, and it, supports the notion that they were. LOL. We could probably dig it out of the web if I wanted to, but, yea, he thinks Sunbwebs blog supports the notion that self-assembling machines are not only a tangibly real, but they require no FF, or can self-replicate with from the energy they produce.

    He did that back in when he constantly linked to articles that not only did support his stupid claims, but flat out contradicted him in almost every case. He even admitted to seldom actually reading the stuff he would paste here. He doesn’t that much anymore, not because of any burning sense of intellectual honesty, or any honestly period,, but simply because I kept pointing out that fact.

    You know, his usual stupid boilerplate.

    You know, with deranged davy having having driven off a good many intelligent posters over the years, I still have to wonder, just who is cloggjew here trying to convince or convert anyhow?

  9. makati1 on Sat, 19th Sep 2020 9:31 pm 

    Anon, I think he is trying to convince himself. He claims to be educated, but if he didn’t understand the Sunweb article, he is the village idiot. I think that is closer to describing his intelligence than any of his claims.

    It has nothing to do with machines making machines. It describes all the steps that are needed from mines to the store shelves that require energy. NET energy. Something renewables will never have in sufficient quantity to scale up to anywhere near that needed to have a “renewables” world. All he can do is point to some electric produced by a few windmills and solar panels.

    We were a “renewable” world when all things were done by animal and human muscle. If we survive the coming extinction cliff, that is the “renewable” world we will again live in. But, by then. the Netherlands will be under water again. LOL

  10. makati1 on Sat, 19th Sep 2020 9:34 pm 

    BTW: Jews believe in cash, gold, money. That is their god. That and the delusion that they are some “chosen people”. One nuke in Jerusalem and they are history. TO bad Ramses was a whimp and let them leave Egypt. LOL

  11. Anonymouse on Sun, 20th Sep 2020 2:37 am 

    For sure right. He let them go because they were a pain in the ass and not worth keeping around anymore. Which is kind of odd because back in the day, a useless slave usually = dead slave(s).

    It wasnt like the slave-master called all the slaves to gather round one day and said.

    “I was hopeing things wouldnt come to this, but weve been talking and you know, you people really arent very good slaves, and clearly, your hearts really are not in it. We were really hoping you would have adapted by now and settled into your life of servitude with no rights of any kind, 14 hours days of back-breaking labor in the hot sun etc etc, but no. You’d think by now it would be second nature to you all, but that doesnt seem to be the case. And it wasn’t for lack of trying on our part, but, it seems none of you appreciate the time and effort we put in enslaving you, and our efforts seem to be mostly wasted, sadly. I have to say, we are rather disappointed with the lot of you, but, the decisions been made
    and its out of my hands. So sorry enslaving you didn’t work out as we had hoped. Anyhow, off you go then, and best of luck in the promised land”.

    Thanks, make sure to clear out your lockers and leave everything as you found it when you got here, please and thanks.

    IoW, that whole story is jewshit as well. No one let their slave population go free en masse, much less that AND let then settle literally next door so they could one day raise an army and drop by one day for some payback.

    Ejecting your jews because they are a fooking PITA, is tactic as old as dirt. Problem with that was, once you got rid of your jews, they because someone else’s problem, then someone else’s, then someone else’s until they became the entire WORLDS problem. And long before that happened, they were still your problem even after you got rid of em. Because they are problem no matter where they ended up.

    Which is where things sit today.

    So yes, shoulda cracked those whips harder. A lot harder..

  12. Abraham van Helsing on Sun, 20th Sep 2020 5:05 am 

    Keep dreaming of that techie heaven where all your techie dreams come true, Cloggie.

    https://sunweber.blogspot.com/2011/12/machines-making-machines-making.html

    Sorry, but the real world is killing your dreams, even if you will never admit it. Dream on!

    Interestingly, makati’s glorified Chinese have mysteriously also embarked on a renewable energy future. Apparently they didn’t take notice of the fail-proof blog of some 85 year old american layman called Weber, makati keeps peddling for years now. He does that to support his a priori desired end result, namely the collapse of western world. Mysteriously not the beloved Chinese.

    I would love to see a picture of makati. Probably half-white, half-Asian.

    Makati ignores all the work done around the world, in Europe, in China, in Japan and even in pockets in the US, like California, Texas and soon in Maine… to make the renewable energy transition work.

    Nay, Weber is da man!

    ROFL

  13. Davy on Sun, 20th Sep 2020 6:33 am 

    “IoW, that whole story is jewshit as well. No one let their slave population go free en masse, much less that AND let then settle literally next door so they could one day raise an army and drop by one day for some payback.”

    One thing about annoy is you can get right to his point of view with Jew and or stalking. He really has no other ideas in his blank mind. This is why he goes by Anonymouse, he is empty of critical thinking. The reason I am here so little these days is this unmoderated forum has a handful of people who comment with a net of zero contributions to advancement of knowledge. Of course, the lunatic JuanP is the worst dumping his mental illness on this ruined forum but there is little else from the others either. Who visits this forum anymore, lunatics and delusionals.

  14. Davy on Sun, 20th Sep 2020 10:37 am 

    woof woof!

  15. Davy on Sun, 20th Sep 2020 5:02 pm 

    From: Po.com moderator
    to: cloggo:
    Re: My comment 6:33 on Sun Sep 2020

    Do not feel that you have to modify your own ceaseless ‘jew-baiting’ in any way. Your constant calls for over the years for the extermination, your calls for genocide, your alleged fawning adoration of Hitler , your holocaust denial and all your other random slurs and calls violence, implied or otherwise against the wonderful jewish race you have graced us with here over the many years are well within my stringent guidelines. So keep up the good jew-baiting cloggo. Your high-brow jew-baiting is fair, balanced and intelligent. As are your claims the holocaust is a fraud. I may not know where Europe is, but I think I heard denying the Holocaust there is actually a crime? Well I dont know if is that true since I have never been out of Missouri myself, but I promise you this cloggo. Jew-baiting will never be a crime on MY watch here.

    UNLESS that idiot anooy does it. Then I will neuter his extremist anti-American stupidity.

    God Bless America. The only real democracy ever.

    It is important you do not construe my comments at the idiot annoy are directed at your fair and balanced jew-baiting in any way. Please keep posting your genocidal, hate-filled diatribes while I continue doing gods works of ridding my forum of the fuckwacks (not you) once and for all, god willing.

    Your Po.com Senior moderator

    Davy

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