Disclaimer
First, I want to make a little disclaimer. In this essay, I will again be discussing the energy balance of gasoline versus ethanol. I am not doing this to suggest that gasoline is a great fuel of choice, but merely to show that grain ethanol is not. Gasoline has its own set of baggage, most notably that it is not sustainable. But the purpose of this essay is merely to examine claims from ethanol advocates who would have us believe that ethanol is actually more energy efficient to produce than gasoline.
Correspondence With Minnesota Dept. of Agriculture
Following my last posting on the energy balance of corn ethanol versus gasoline, I got into an e-mail exchange with an official from the Minnesota Department of Agriculture. I pointed out to the official that a claim that can found on their website is simply not correct. In part, the claim reads:
In summary, the finished liquid fuel energy yield for fossil fuel dedicated to the production of ethanol is 1.34 but only 0.74 for gasoline. In other words the energy yield of ethanol is (1.34/0.74) or 81 percent greater than the comparable yield for gasoline.
I won’t identify the official by name, but I will show that his responses were vacuous and devoid of any logic or calculations to back up his point. In his first response, he wrote:
It appears that you may not be considering that all 115,000 (more or less) BTU’s of energy that exist in a gallon of gasoline are solely derived from the crude oil that was also used to extract, distill and refine it. Only in this way could you come to the conclusion that the gasoline production and refining process yields more energy than it consumes. In fact, no matter how efficient the process of oil exploration and refining becomes, the energy yield for gasoline can never be positive because each unit of energy in the finished product also must be added to the total oil consumed in the production and refining of crude oil.
So, he is suggesting that by definition, the energy yield for gasoline can’t be positive. That’s all well and good, and I understand that, but then they do not use the same definition for calculating the energy yield of ethanol. I responded:
No, I understand quite clearly. What the USDA, and you by extension, have done here is to make an apples and oranges comparison. Consider that I wish to produce 10 BTUs of energy. I can use 1 BTU to pump oil out of the ground, and 1 more to refine it, netting 8 BTUs. This is where the claims of roughly 80% efficiency come from.
Now, let’s do the same exercise for ethanol. To produce 10 BTUs of energy, given an energy return of 1.3, requires that I invest 10/1.3, or 7.69 BTUs. I only net out 2.3 BTU, or barely over 1/4th of what I would get for investing my BTUs into gasoline production. That is a true apples to apples comparison using the same metric.
There may be some legitimate reasons for producing ethanol, but energy efficiency is not one as my calculation has shown. My calculation and conclusion are correct. If you work through the math, you will see the same thing. What is shown on your website is misinformation.
Sincerely,
Robert Rapier
He then followed up with:
I disagree with your contention. You are still ignoring 80% of the energy required to provide gasoline. According to the report you reference, one Btu of fossil energy yields 1.34 Btu of ethanol.
No calculations or logic to support his position. He is simply ignoring the fact that the two methods of measuring efficiency are using completely different methodologies. When you compare ethanol to gasoline using the same metric, ethanol always turns out to be far less efficient. So, I again responded:
I am not ignoring anything. I am just showing the energy investment required to produce 10 BTUs of gasoline, versus 10 BTUs of ethanol. The energy investment is always much higher for producing ethanol. That is a true apples to apples comparison. The “80% that I am ignoring” are the contained BTUs in the crude oil that end up getting turned into gasoline. This is comprised of captured solar energy, as in the case of ethanol, but in the case of gasoline the solar energy was captured over many years instead of a single growing season.
Again, let me put it to you another way, and I think you will see the problem. Assume I have 10 BTUs of energy to invest. How many BTUs of usable energy will I have left if I invest into producing gasoline from scratch (i.e., starting from crude oil in the ground) versus investing the 10 BTUs into producing ethanol?
Here is the math, if you don’t wish to work it out. In the case of gasoline, my 10 BTUs will generate about 100 BTUs of crude oil, since the energy return on energy invested for crude oil is about 10 to 1. It will then take about another 10 BTUs to refine the oil into gasoline. So, for my 10 BTU investment, I netted back 80 BTUs of gasoline.
In the case of ethanol, for a 10 BTU investment, I only got back 13.4 BTUs. I only netted 3.4 BTUs.
I can understand that you might disagree. But your disagreement needs to be backed up with some actual calculations showing where my contention is wrong. Please set up any case you like, as long as the comparison is apples to apples. I am confident that you can’t show a case in which ethanol production is more energy efficient than gasoline.
Sincerely,
Robert Rapier
After my last response, I never heard from him again. I really wanted to see him back up his claims with some calculations. Perhaps he tried to do it, and got my point. Or perhaps it doesn’t matter anyway to him, since a lot of people involved in agriculture don’t seem to care about the energy balance, as long as it benefits corn farmers.
Gary Dikkers Reports a Similar Experience
I would also point out that Gary Dikkers indicated that he had a similar exchange with the MN Dept. of Agriculture. Gary had previously written in the comments section of an earlier essay:
Last month the USDOT released the fuel consumed/miles driven for each of the 50 states in 2004. Just for kicks I compared Minnesota (which has mandated ethanol) to Wisconsin (which does not.) The two states are near twins with similar weather, topography, and about the same mix of urban/rural population.
In 2004, the average fuel economy for the entire State of Minnesota using E10 is 20.62 mpg. The average in Wisconsin is 23.30 mpg.
By adding 10% ethanol to their fuel, Minnesota drivers ended up burning 13% more fuel than their Wisconsin neighbors.
After my last essay, Gary indicated that he had also corresponded with the MN Dept. of Agriculture:
Yesterday I sent him the USDOT data showing the large differential between fuel economy in Minnesota with E10 and Wisconsin without ethanol, and he is having trouble getting his mind around that. Says it can’t be true.
Correspondence With Michael Wang
Finally, I had tried to elicit a response from Michael Wang at Argonne, who seems to be the source of these claims about energy efficiency. I had also written to him to show him that his claims could not possibly be accurate. He finally responded. In part, he wrote:
Our calculations on energy are separated into total energy, fossil energy, and petroleum energy. Depending what type of energy you are looking at, results are very different. I believe that you are talking about total energy.
Well, of course I am talking about total energy. Can you make ethanol or gasoline without the total energy? Why on earth would someone not count the total energy, unless they are playing games? Frankly, this statement from him didn’t make much sense to me. I know that these guys are just playing games to exaggerate ethanol’s allure, so I responded:
Hi Michael,
Thanks for the response. I have read quite a few of your publications, as well as Shapouri’s. I also exchanged e-mails with Shapouri last year on this subject. It really seems to me that you are playing games with numbers to try to make ethanol look better than it really is. I think that you are not making consistent comparisons between gasoline and ethanol production. When I see someone say that gasoline is 80% efficient and ethanol is 130% efficient, they are always using different measurement metrics.
Can you show me any case in which an apples to apples comparison shows ethanol to have a better energy balance? We can do solar energy if you like, but fossil fuels are a very rich source of captured solar energy with a much greater BTU value per unit volume. It is hard for me to see how ethanol is going to win that matchup. But if you have a specific publication, or a specific example in which you can show that ethanol has a superior energy balance, I would like to see it. I can tell you that if I have X BTUs to invest any way I like, I will get about 4 times the BTU value by investing in gasoline over investing in ethanol. That is quite an easy calculation to show, and is essentially the calculation I showed in my first e-mail.
I would support ethanol if I thought the energy balance was very good, but from what I have seen it is not. All I see are some very misleading arguments designed to show ethanol in a more positive light than reality would dictate.
Sincerely,
Robert Rapier
So far, no response. I don’t expect to get one. It seems that whenever I ask an ethanol advocate to back up their assertions with some calculations to support their argument, they immediately clam up.
Are there any ethanol advocates out there who would like to back up some of these claims with some calculations? I guess I need to issue a debate challenge to see if I can get someone to actually actually defend ethanol with calculations.
RR,
The poor EROEI of ethanol doesn’t matter if you use a cheap, non-liquid form of energy (like coal) to do the distilling etc. If you proceed that way, then ethanol can be regarded as a form of “coal liquefaction”, and the low EROEI doesn’t matter. The question is whether coal liquefaction via ethanol is more cost effective than coal liquefaction via other routes.
JD
Hi JD,
I addressed that very topic in my essay Improving the Prospects for Grain Ethanol. I believe that this is the future for ethanol plants. It certainly is not an environmentally attractive solution, though. As far as coal liquefaction by other routes, I think coal based methanol will be a much cheaper option, but the ethanol advocates will certainly play up the toxicity of methanol.
RR
Should’ve known I wouldn’t catch a sharp guy like you with your shoes off. 😉
Thanks for the link!
By the way, I’ve been reading your site. It makes me feel a bit more optimistic (although I am not a doomer anyway).
RR
Well, you forgot to mention that the production of gasoline needs digging a huge hole and (sometimes) pumping the oil out of this hole besides transportation and distilation, just like ethanol. All those consume a lot of energy.
Brazil produces ethanol with an EROEI of 5 to 11 (thus, highter than gasoline), already delivered to the consumer. If you or any other reader happens to speak portuguese, here are some data gathered from scientific journals. And all brazilian ethanol byproducts are eletricity sent to the grid, that is not accounted on those numbers.
Ethanol is viable. The United States may not have the technology to produce it, but that doesn’t means that it is impossible. And people would buy gasoline even if you get a highter EROEI out of ethanol just because it is cheaper.
Hi Marcos,
All of those things you mentioned are taken into account in the EROEI of gasoline. The far superior EROEI of gasoline over grain ethanol is why gasoline is cheaper.
My understanding is that the EROEI of sugarcane ethanol is much better than for grain ethanol. Someone just sent me a technical paper on the process and I will read it on Monday. My position is not that ethanol production needs to have an EROEI as good as for gasoline, but it needs to be much better than it currently is (around 1.3).
RR
Did anybody take into account the energy required for a dinosaur to run into a prehistoric corn field, eat the corn, and digest it? What about all that geothermal energy required to convert the dinosaur into crude oil in the first place?
When you take into account all the BTUs required to turn plants into crude, maybe ethanol is more efficient 🙂
Did anybody take into account the energy required for a dinosaur to run into a prehistoric corn field, eat the corn, and digest it? What about all that geothermal energy required to convert the dinosaur into crude oil in the first place?
Slostang,
Petroleum doesn’t come from dead dinosaurs. It is made mostly of billions of tons of algae and plankton that settled to the bottom of the seas over millions of years and then was metamorphosed through heat and pressure into oil. Besides algae and plankton, there is also a component made of other organic matter such as giant ferns, leaves, etc.
The energy in petroleum is really sunlight that arrived on the earth millions of years ago and was captured by organic plants and organisms as they grew taking in carbon dioxide and water. Oil is nothing more than an organic compound resulting from a mix of sunlight, carbon dioxide, and water — and millions of years of heat and pressure.
I’ve always been puzzled that oil isn’t considered a renewable resource. The truth is it is both organic and renewable. The big problem of course is that the renewal cycle takes millions of years, and we can’t wait that long with our 70+ year life spans.
That also helps explain the reason making ethanol is not very efficient. To make ethanol, farmers and ethanol plants must accelerate what nature would be content to do in 75 million years down to a few months. It takes lots of energy to accelerate what would be a natural (but slow) process into a short time.
The most efficient way to make ethanol would be be to bury corn and wait 75 million years — nature would then turn it into liquid fuel for free. Of course that is impractical, but to speed up that process we do have to spend energy.
As Robert Heinlein famously said, “There ain’t no such thing as a free lunch.”
Ethanol is viable. The United States may not have the technology to produce it, but that doesn’t means that it is impossible.
Marcos,
Thank you for your input.
It’s not so much that we don’t have the technology to produce ethanol as you do; it’s more that we don’t have the favorable conditions you do. Here are several reasons, you can be independent using cane ethanol, and that we can’t:
1. It is much more efficient to make ethanol from the sugar in cane than from the starch in corn.
2. You have vast tracts of undeveloped and available land at the tropical latitudes needed for growing cane. (There are only four of our states suitable for growing cane. Parts of Florida, Louisiana, southern Texas, and Hawaii.)
3. You have an abundance of inexpensive, machete-swinging, manual labor. Our farmers are much more likely to drive tractors and harvesters each burning 25-30 gallons of diesel fuel per hour than to wade into a field swinging a machete. (And who can blame them?)
4. And most importantly, your per capita energy consumption for transportation is only 12% of ours. (I know, don’t tell me. I already know we are energy hogs.) If you suddenly increased your energy consumption for transportation by a factor of eight, you would need to import oil also — no matter how much rain forest in the Amazon Basin you cut down and converted to cane plantations.
The real solution for us is not cane ethanol, but learning to live comfortably while burning far less energy. Unfortunately, I don’t think we are likely to learn to do that until the wolf is at the door.
Gary – I was trying to be humorous (as noted by the smiley) in an attempt to mock the Dept. of Agriculture.
I knew vaguely that oil is ancient biomass of some sort (and probably not really “dino juice”), and enjoyed your excellent and detailed description of how oil really is formed.
If there’s a serious point to be made at all in my post, it’s that the millions of years of heat and pressure could be counted as an energy input if you wanted to calculate the EROEI of making oil “from scratch”. I can’t imagine a good reason for doing this, unless you work in ethanol marketing.
Gary – I was trying to be humorous (as noted by the smiley) in an attempt to mock the Dept. of Agriculture.
My apologies, I didn’t catch that.
Best,
Gary Dikkers
“if you use a cheap, non-liquid form of energy (like coal) to do the distilling etc.”
Burning coal sounds like a good idea until you start to think about the details. Problem is coal is nasty stuff to burn. It releases tons of polutants such as sulfur and mercury and creates lots of particulates. The utility industry has been fighting these problems for years, but they have run out of grace and time. The next generation of coal fired electric plants will “gassify” coal, which is expensive and resource intensive. Having to jump through that hoop destroys the case for using coal to boil corn liquor.
If you gassify the coal, you can just use some of the syngas to create methanol or other fuels. No need to plow uphalf the country.
Robert Schwartz said, “The next generation of coal fired electric plants will “gassify” coal, which is expensive and resource intensive. Having to jump through that hoop destroys the case for using coal to boil corn liquor.”
Robert,
Gasifying coal IS energy intensive and not cheap, but that’s also the case with corn ethanol.
But there is a difference: Coal is a true domestic fuel. We have enough coal in Wyoming and Montana to last us perhaps 200 years or so. It’s our coal, and there are no geopolitical issues involved with using it.
That’s not the case with corn ethanol. Modern industrial corn production is entirely dependent on nitrogen fertilizers made from natural gas. And right now we import almost 60% of the nitrogen our farmers use after its made outside this country from foreign natural gas. (Corn ethanol producers are as addicted to natural gas as the rest of the country is to oil.)
…you can just use some of the syngas to create methanol or other fuels. No need to plow uphalf the country.
Correct. We should use all that coal as a feedstock for methanol and synthetic diesel fuel. No need to go through the middleman of having farmers consume energy to grow corn in order to turn that corn into fuel alcohol using more energy.
Which looks more efficient?
1. coal -> syngas -> methanol or diesel (the coal originally came from carbon dioxide + water + sunshine + millions of years of heat and pressure)
2. natural gas -> nitrogen fertilizer + water + sunshine -> corn -> more natural gas or coal -> ethanol
Ethanol is really an immature fossil fuel in which we replace millions of years of heat and pressure with some type of thermal energy to accelerate the process. Unfortunately, very few in the ethanol industry will own up to that fact.
Best,
Gary Dikkers
SloStang: “I was trying to be humorous “
Well, I think you did great, SloStang! Was laughing hard when I read that dino argument 🙂
Hi Guys,
Re. Oil Peak, I have a question, that seems to fit in this forum…
I recently heard abt this Fischer-Tropsch technology where you can produce diesel or gasoline from coal, and was surprised I never even heard of this before, even though it’s been in industrial use since WW2.
The info I got was that you can produce a barrel of “ultra-clean” diesel/gasoline for ca US$35, and South-Africa already used it for decades during the Apartheid oil blockade, to produce the bulk of their tranportation fuels. Also, using this method, US has enough coal-reserves to meet current demands of transportation fuels for more than 2 centuries.
From the above data, this seems like the obvious Oil Peak solution for the to me, but are they correct?
What is your input on this?
What are the drawbacks?
The energy balance I have no info about — do you know how good/bad it is?
The comparison of actual mileage in the two states is the most damning number for E10 possible. Adding 10% ethanol to the fuel mixture accomplishes…nothing. Not 6% more energy, none. Why? The Lambda fuel injection controller notices more oxygen in the exhaust stream and richens the mixture.
The energy equations for E10 calculations should all take into account the 0 net energy. Doing the calculations in miles or dollars should make this clearer.