Perpetual Confusion over Energy Balances

People continue to be confused about the energy balance of gasoline versus ethanol. The ethanol lobby, in my opinion, deliberately spreads this sort of misinformation to persuade people that producing ethanol is a wise usage of our BTUs. I have tried to clear up the confusion on a number of occasions, most recently when Vinod Khosla once again claimed “corn ethanol has almost twice the energy balance compared to gasoline“:

The Handy-Dandy Khosla Refuter

But the issue lives on, as strong as ever. A couple of days ago, Stuart Staniford wrote the following essay at The Oil Drum:

The Fallacy of Reversibility

In the essay, Stuart takes on one of the major tenets of many peak oilers: That peak oil will mean a return to localized agriculture. Stuart argued that it would not. I warned him that he would take his lumps for arguing against a popular position (and he did) just as I did when I have argued against the peak oil conventional wisdom that Saudi oil production has peaked.

But in that thread, the energy balance issue once again came up. And here was one response:

I hate to jump in because I went round and round with RR on this a while back, but also because I think the costs of ethanol are being externalized, particularly water costs, and I don’t like seeing food go to fuel. But I agree with you. The slight-of-hand that Nate is using is that he ignores the oil feedstock when refining oil, but you have to include it when making ethanol (system boundaries have to be drawn that way I have been told), so you get this 8:1 number for oil refining and 1.3:1 for ethanol, and all the “awl bidness” folk say QED.

BUT… for grins, lets suppose all the oil you had in the world was 1800 barrels. When that is gone you are out, kaput, no more. Then you can ask what will I do with this. Well you could pump and refine it into diesel using 200 barrels and ending up with 1600 barrels of diesel. 8:1 OK well and good.

Or you could take take that 1800 barrels less pumping cost (let’s say negligent for argument sake) and produce 2340 (1.3 x 1800) barrels of oil equivalent in ethanol.

Now for further grins, let’s assume that the usage is 540 barrels per year. Having pumped and refined diesel you will be out, kaput, done, in about 3 years, but when making ethanol, each year, when a new crop is planted you will still have 1800 barrels, and now you have a sustainable energy supply. Woohoo!

Now these “ethanol haters” will rightfully claim that we can’t replace our current FF useage with ethanol, ignoring the fact that they have been spouting nonsense about efficiency of oil versus ethanol. But with the right ethanol production from say celulosic sources, we could ease the burden on the oil consumption extending our nonrenewable resources, particularly so, if we also agressively conserve oil and recycle some of the water used in ethanol production. Here you will be told that the “devil is in the details”, because there is no viable celulosic process. But hold on now, GE just invested in just such a process, with the idea that they could build many plants and replace about 15% of the FF use in the future. The first plant goes on line this year if everything goes perfectly :). Anyway, you’ll go blue in the face arguing with some of these folk as they set system boundaries to ensure that oil refineries appear efficient compared to ethanol, wihtout a thought for extending the present supply of FF.

Naturally, I responded to it:

You were wrong the last time, and you are wrong now. You are not making an efficiency argument. The argument “what if there was no more oil…” is not an efficiency argument. You are correct, if there was no more oil, then it’s a different argument. But then if there was no more oil, the whole charade would come tumbling down anyway.

The oil feedstock is ancient, captured solar energy. You do not include that when doing the energy balance, any more so than you include the corn BTUS – recently captured solar energy – when doing the ethanol EROEI. (What you do include is the portion of the BTUs that were due to the fertilizer). This is what you, and so many others who are confused on this issue do not see.

What is counted in the ethanol EROEI is the energy it took to grow the corn, turn it into ethanol, and purify it. What is counted in the gasoline EROEI is the energy to extract the oil and to refine the oil. The portion of the feedstock BTUs that amount to captured solar energy are not counted in either case. Ethanol proponents wish to count them in the case of oil but not ethanol, which is why they say nonsensical things like “It is more energy efficient to produce ethanol than to produce gasoline.”


I think it’s that captured solar energy portion that they don’t seem to get. It’s really not that difficult of an argument, in my opinion. And the argument often shifts, as it did above, to “suppose we had no more oil….” But that is not an efficiency argument. It is a valid argument, just not an efficiency one. But as we debate that argument I think we need to understand, as a society, what it means to transition from an energy return of better than 5/1 in the case of petroleum to something that is around 1, plus some animal feed that gets counted as a fraction of a BTU.

11 thoughts on “Perpetual Confusion over Energy Balances”

  1. Wow, thanks for the link to Stuart Staniford’s article on the Fallacy of Reversibility. I am not a regular reader of TOD, so I would have missed it.

    I am involved in US industrialized agribusiness, and have been all my life. Stuart is spot on with his excellent analysis. I found this to be his key statement; “Instead, the farmers will simply outbid the urban poor for the energy required to operate the farms…”. That is EXACTLY what’s going to happen.

  2. Odo – eliminate food subsidies as well. One of the most onerous is sugar. Import tariffs protect a few wealthy growers at the expense of whole Caribbean economies.

    As food prices shift, people will change their eating habits.

    Did Staniford take into account daily caloric intake? As an office worker I can get along quite nicely on 3,000 calories a day. As a farm laborer I would need maybe double that. Producing food the old fashioned way requires more food.

  3. Odo – eliminate food subsidies as well. One of the most onerous is sugar. Import tariffs protect a few wealthy growers at the expense of whole Caribbean economies.

    That would be nice, wouldn’t it?

    I’ve been throwing a few links at my blog about debt and stimulus. I’m not sure the picture is clear yet, but it’s possible that we all (individual, business, state & federal governments) will have to pay down our debt. Dropping the “subsidize everything” model would certainly help.

    On calories per day … boy is that complicated by both market realities and government subsidies. If I’m remembering correctly a fresh carrot calorie is more expensive than a sirloin calorie.

  4. One more exchange between my very confused opponent and me. First up, my opponent who thinks corn is captured sunshine, but oil is something else:

    I disagreed with you last time and I do so again. You ignore the crude oil feedstock as though it was not an input to crude refinement. In doing so you come up with this specious argument about efficiency. Moreover oil *is* a finite resource and production *is* constrained, so the main issue really should be about “can ethanol production increase our total energy production without hurting us more in other ways.

    This 8:1 ratio is misleading. You don’t get 8 BTUs out from 1 BTU in. That is called perpetual motion and violates the first law of thermodynamics. What really happens is you input 8 BTUs of crude plus 1 BTU (also from crude in steady state) to refine it, and get 8 BTUs out. 9 BTUs in, 8 BTUs out, so your efficiency in refining is 8/9 or less than one. In ethanol production, the sun’s energy is captured in the growth of the feed stock for the ethanol production so that with 1 BTU of oil plus sunlight you get 1.3 BTUs out, so with respect to the BTUs of oil consumed, your efficiency for ethanol production is 4/3 or greater than one.

    So here is where you will claim that I haven’t drawn the system correctly, but as before, I think your argument is sophistry.

  5. And my response. I will be surprised if he continues, because I think this is understandable for anyone:

    My Opponent: I disagreed with you last time and I do so again.

    Me: And as I said, you were wrong last time, and you are wrong again.

    My Opponent: You ignore the crude oil feedstock as though it was not an input to crude refinement.

    Me: As you ignore the corn feedstock. You are treating the BTUs from corn differently than the BTUs from oil, and this is why you come up with the wrong answer. Look carefully at your second paragraph. The error is glaring. Here’s a hint: In oil production, the sun’s energy is captured in the growth of the feed stock. Just as soon as that sinks in, you will understand why you are wrong on the efficiency issue. The efficiency greatly favors oil. We can argue about other aspects, but the efficiency issue is settled.

    Once more, with corn: You spend BTUs to fertilize and grow the corn, to harvest the corn, and to produce the ethanol (which is soluble in water, and energy intensive to distill). Those are the BTUs charged against your process. What is not being charged is the captured solar energy, which is how you can input a BTU and get more than a BTU out.

    With oil: You spent no BTUs fertilizing or growing the ancient biomass. The earth has processed it into crude oil (which is insoluble in water, and not as energy intensive to distill). Where you do have to spend energy is getting it out of the ground and refining it. Those are the BTUs charged to the process. Just as in the case of corn, what you are not charging against the process is the captured solar energy. The excess BTUs that you got out are simply due to the ancient, captured solar energy.

    My Opponent: So here is where you will claim that I haven’t drawn the system correctly, but as before, I think your argument is sophistry.

    Me: Pointing out that your argument is comparing apples to oranges is not sophistry. And this is not rocket science. This is straightforward.

    Here’s a test. You and I each get one barrel of oil to invest as we please: Into oil production, or into ethanol production. Who will return the most BTUs from their investment?

  6. Apart from perpetual confusion about perpetual motion (sustainability!), the pro-ethanol choir misses at least (but not limted to) the following details:
    1. Converting food into fuel is a crime against humanity. Period. The only allowable feedstock for renewable fuel is inedibles, and preferably waste products. DoE are you listening?
    2. Ethanol is a terrible fuel, due to its properties. These include, but are not limited to:
    2.1 The fact that it absorbs moisture, leading to corrossion trouble and eventually to a useless fuel.
    2.2 It increases the vapor pressure of ethanol-gasoline mixtures, increasing emissions and evaporative loss.
    2.3 It burns with a colorless flame – WHOOF!
    2.4 Producing it through fermentation is as dumb as rocks. No amount of genetic engineering or clever enzymatic technology will change that. It simply takes too much energy to separate the resulting ethanol from the fermentation broth. After separation your problems start all over again, as pointed out under 2.1.
    3. Finding a brand new fuel may be exciting (ethanol! biodiesel! biobutanol! etc.), but it pretty meaningless. These things can all be made (sometimes very indirectly) from crude oil. The point is to find a replacement for crude oil. Under the present system it would be most helpful to convert that alternative to gasoline and diesel (or something miscible with those) so that we don’t have to replace the entire fuel supply infrastructure and our vehicles.
    4. Nothing against farmers, but they are not a part of the energy supply chain, other than residues not needed for soil conditioning. As long as there is starvation out there, there is no excess of food.
    5. Ethanol is best used for internal human consumption. Cheers!

  7. I have disagreed with your (Robert’s) arguments and think the views of your disputant are far more valid and applicable to our present situation. You focus on “efficiency” as defined by certain parameters when that is largely irrelevant to the practical decisions we need to make as a society.

    By your definition, solar panels are extremely inefficient, capturing only 6% or so of available solar energy. Yet with the new low cost panels this may nevertheless be an extremely cost effective and economical way for society to invest its resources. Your focus on efficiency would suggest that solar panels could never be competitive with fossil fuels, but that is not the case.

    I think this is why you get so much push-back when you promote the idea that fossil fuel refining is more efficient than ethanol production. Anyone can see the truth of the argument that your disputant produced, that given a fixed amount of fossil fuel (which is exactly the situation we face!), we can in principle get more mileage by using it to produce ethanol than by converting it directly to gasoline. In effect we amplify the energy in the fossil fuel by mixing in solar energy, something that is not possible with straight refining.

    Now, I agree that there are many other problems with ethanol production, that make it a poor choice, and I am glad to see that the ethanol bubble appears to be popping. But the fact remains that your argument about efficiency is irrelevant to this issue and uses an artificial measure that does not shed light on the true merits and problems with the various energy options that lie before us.

  8. your argument about efficiency is irrelevant

    Hal, you miss the point. When someone says “it is twice as efficient to produce ethanol”, or “the energy balance of ethanol is twice that of gasoline”, a discussion of efficiency is not irrelevant. The argument being put forward is wrong. Your focus on other factors, when the claim made was in regards to efficiency, is what is irrelevant in this context.

  9. By your definition, solar panels are extremely inefficient, capturing only 6% or so of available solar energy.

    Incidentally, if that’s what you think, then you don’t understand my argument at all. The energy output would be measured over the lifetime of the solar panels. The equation would be how much total energy was output over how much total energy to make the panels. That is going to be highly efficient.

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