An Energy Analyst's Viewpoint on Corn Ethanol
I urge our readers to check out this article that Glenn Doty, an extremely senior energy analyst and frequent commenter here at 2GreenEnergy, wrote on corn ethanol. Glenn asked me to respond, so here goes.
I totally agree. I’m not a fan of biofuels generally, based on the basic thermodynamics. Organisms did not evolve to store lots of chemical energy they don’t need, just so we could harvest it and put it in our gas tanks. This is why the efficiency of solar energy is orders of magnitude greater than biofuels; almost all of the sun’s energy that is absorbed by the plant goes into the organic processes required for survival and growth.
To the degree we still have a civilization here in 100 years, I believe that the people of that day will regard our efforts at biofuels with the same mixture of pity and contempt that we have for those who treated disease with leeches and bloodletting. Future generations will marvel: “The people of the early 21st Century lived in a time when their scientists were telling them three things: a) their population was in the process of quintupling in size to 10 billion in under 100 years, b) demands for energy were exploding far faster than the population growth alone would suggest, and c) climate change was bringing shortages of potable water and food. And they thought it would be a good idea to power their cars and trucks with their vegetables?”
Of course, corn ethanol is the most egregious case, the worst of all possible worlds, for the exact reasons you name in your article. But let’s be fair: the concept came into being in an era before our concern with global climate change, where the primary driver was a substitute for foreign oil. Now, of course, it continues, but only because of corruption: the influence of powerful senators in the corn belt, who themselves are fattened by the industry itself. It’s just one of many depraved energy-related practices under which we suffer here in the U.S., all with the precise same root cause: the collusion between big money and politics.
Btw, if you can help me do something about that root cause, I’d sure appreciate it.
Thanks again for another excellent article.
Thanks, I like your perspective, I am smiling, you made my day better.
“Bloodletting”, Right on….
Well, if you’re smiling, so am I. Coincidentally, I just now read this poem on the subject:
Count That Day Lost
by George Eliot
If you sit down at set of sun
And count the acts that you have done,
And, counting, find
One self-denying deed, one word
That eased the heart of him who heard,
One glance most kind
That fell like sunshine where it went —
Then you may count that day well spent.
But if, through all the livelong day,
You’ve cheered no heart, by yea or nay —
If, through it all
You’ve nothing done that you can trace
That brought the sunshine to one face —
No act most small
That helped some soul and nothing cost —
Then count that day as worse than lost.
Craig,
Thanks for the link!
🙂
The thing that is really interesting is the fact that we’re going to lose roughly half the crop this year, but we were growing roughly twice as much corn as we needed. IF the mandates are abandoned then the ethanol infrastructure would have been an invaluable path to maintaining food supply… but if they are not abandoned then they will be directly contributing to human suffering.
There are good points to HAVING an ethanol industry – so long as we are smart enough to know when not to use it.
Yes, per-acre yields continue to rise as we keep getting better with genetic modification and the chemistry in fertilizers and insecticides.
As if THOSE were were good things…
But…………… Who are you kidding? The soil cannot support ethanol production and food together. We are rapidly exploiting topsoil today at alarming rates but they are, just like global climate change, conveniently deniable. Our subconcious guilt requires our grievances now be projected out onto the world, having killed all enemies we can make; yes, we made them. Our guilt says we must combat our enemies in mind, because we have lost all sense of power in our guilt infested mind. We believe we are form, not content. Therefor, the form must be reacted to, because the content of our minds has become insane, and un-recognizeable. And you learned men still believe that the corrected facts will save what you prefer to see, though it is false and impossible to maintain at the current levels. Everything must change, or, everything will change in ways we cannot imagine now.
I come from the Midwest and find it interesting how farmers found a way to dry there corn, generate feed for the livestock and be subsidized, TWICE.
Corn ethonal is a fine example of our government waste. Forrest Gump sez it best. Stupid is as stupid does!
If anyone were to try and design a more outrageously inefficient means of personal mobility they would have difficulty beating the average ICE vehicle. Amory Lovins has done his usual thorough analysis concluding that cars are something less than one percent efficient at moving the driver. (the engine being about 20% efficient at best and most of the energy of course going to move the two tons of steel)
Ken Regelson has done an analysis of various biofuels compared to PV charged EVs done in miles/acre/year
http://evworld.com/insider.cfm?archyr=2007&nextedition=133
Ethanol (Corn) 18,000
Solar Photovoltaics 2,250,000
Perhaps we should look at vertical farming, as described in Peter Diamandis’ book, Abundance. This involves growing crops in skyscrapers with climate control, hydoponics, etc. “Farms” can be located in population centers to reduce transportation energy use and costs. Crops could be “tuned” to give biofuels or food as needed, with the emphasis on providing the needs of the people first.
The drawback I see in this is Diamandis’ acceptance of GMO plants, something which could have long-term negative consequences.
The idea is that droughts and crop diseases would be a thing of the past, although one wonders whether this is a Pollyannish notion.
Damages to fauna from GMO’s have now been documented in myriads of places: Tyrone Hayes, from UC-Berkeley is the most colorful and entertaining, see his TEDx talk, but the research in FL on alligators preceded him, and the outrage of Colbert, when Nicholas Kristof came on, speaking of the mutated “fish junk” also preceded him, as did research from the TEDX (endocrine-disruption exchange). Work in France and Russia and even Scotland (whistleblower crucified, the modern way) also confirms this. The bad guys cannot keep up their intimidation for much longer. They picked on the Amish in the 70’s too, but it is ungentlemanly and just plain un-manly to do this. The jig is going to be up pretty soon, in my estimation. The Army wants solar, and the Navy wants algae. They are both fed up with energy systems they see as endangering national security, not to mention convoy- and field/sea- security. Sheesh. Meanwhile, what if we turned kudzu into fuel instead of poisoning the deep ground to get rid of it, duh. Ethynol works for NASCAR. You could fuel with this, and there was a funny story about this a few years ago. So many humans have a slow learning curve, but we need to sharpen up, soon.
Also, see Stephen Brooks, Costa Rica, TEDx talk. He is generating gas from compost, somewhat in the manner of Jean Pain, if I understand correctly. There is also another guy in India doing this, but I cannot remember the key words to find him offhand. There is a thread on permies.com where they have been discussion Jean Pain’s method.
Energy comes from the Sun or atomic annihilation in nuclear reactors which is how the Sun makes it too. At 93 million miles away the sun is a marvelous energy and we get so quickly because it is all downhill from Sun to Earth. There is NO Other energy source, Wind, Hydro, and Geothermal it all originated with the Sun so put up solar PV panels on every barn roof, Garage roof, House and shed roof and every porch and breezeway roof. We must find and publicize that cheep and simple Solar PV panel manufacturing method from screening, and layers of paint like materials that will waterproof our roof and generate power for the home and car !
Glenn,
Interesting to follow your American debate on fossils vs renewables from biomass. You just touched your excellent idea of renewables from CO2 chemically directly without going via photosynthesis and biomass. This concept of mimicking photosynthesis instead of copying it is also the Chinese route, but the use coal as carbon source to produce alcohols & ethers. I would like to hear more about that. If I got it rightly you ignore methanol in favour of ethanol and buthanol. Why?
Jan-Gerhard,
We don’t see much potential for methanol to ever be competitive. It will never be preferred for an automotive fuel in the first world, as the energy content is low, vapor pressure is high, and it is far more toxic than even the worst gasoline blends the U.S. used in the 60’s and 70’s – which have long since been banned.
So there is a limited market for methanol, and that market will almost certainly be filled with highly-polluting coal-to-methanol processes from China.
Our clean fuels, made from recycled CO2, will have more expensive feedstocks than coal-to-anything; so in order to have a product that viably competes we must have an assured market that has significant value/MJ of energy. The high-energy petroproducts such as diesel, jet fuel, gasoline, butenes, propylene, butanol, and high-value solvents that can be synthesized via Fischer Tropsch are clearly a better choice – in terms of value of products – than methanol and methane.
The key must be to have an openly competitive process. Otherwise it will never outgrow the government support – which is fleeting (ask the ethanol industry, which has never been competitive).
🙂
Glenn,
Thanks for your answer. However, I am still not convinced that methanol is that bad.
I don’t oppose for provoking but for learning. Please don’t hesitate to crumble my arguments!
1) Energy content is low. Sure – 1 oxygen atom in the molecule has the same weight as 1 carbon + 4 hydrogen atoms together. What a fine ballast facilitating combustion and deminishing the need for nitrogen-containing air rendering extremely low NOx values.
2) Only 1 carbon atom in the molecule. Thus no C-C bonds and no soot, particulates and other rotters in the exhaust. The problem of cold start formaldehyde must be solved if it isn’t already so.
3) Toxic. Sure – toxic to our organism but not to earth and water when spilt.
4)Methanol’s vapor pressure is high, but gasoline’s is much higher.
5) Methanol production is increasing not only in China but globally. Methane to methanol synthesis now so simple and ripe that even small natural gas deposits are no longer flared but chemically transformed into methanol in absence of pipeline. Methane to methanol is more often replacing LNG/CNG as methanol is a liquid between -97 and +65 *C. As such methanol contains per liter more hydrogen than liquid hydrogen at staggering -253 *C. Merchant marine in Northern Europe must soon observe hard sulphur regulations and will probably choose simple and cheap bunker methanol instead of complications in connection with expensiv LNG/CNG.
6) DMFC is increasing from W to kW power output and may soon be range extender in BEVs. Already so among fork-lift trucks. Thus methanol may phase out ICEs as well as phase in EVs. The infrastructure is already in place needing only small modifications.
7) China has officially declared methanol/DME for main replacement of gasoline/diesel, “Alcohol&Ether Fueled Vehicles”.
8) The ultimate form of recycling, CO2+3H2>CH3OH+H2O, is no longer any problem – the problem is freeing hydrogen from water by means of energy-intensive electrolysis. Could direct solar photolysis become a better option?
Best regards and hoping for your patience
J-G Hmg
Jan-Gerhard,
I’m a patient person.
🙂
As for your points, there are quite a few things that are incorrect or not fully considered. I’ll go through your points one at a time:
1. I’m far more concerned with energy/volume than energy/mass. Methanol has ~60 MJ/gallon, gasoline has more than twice that. This means methanol must have double the gas tank, double the engine size, double the piston size, etc… greatly increasing the mass that must be pushed around to transport humans, as well as greatly increasing the potential for pressure loss/unit energy within the system. Gasoline, jet fuel, and diesel are preferred because of their extremely high energy/volume. That is a critical advantage for any fuel.
2. Soot isn’t caused by C-C bonds. It’s caused by various chemical reactions at high temp. The most common cause of coking after combustion is the Boudouard reaction:
2CO -> C + CO2. Coking will always be a problem to some extent in the presence of combustion of hydrocarbons… and there will always need to be some platinum on hand to re-catalyze that coking. Proper fuel/gas blending helps more than fuel switching.
3. I’ve found that our society seems to place a premium on human life.
🙂
4. Methanol’s vapor pressure at room temperature is ~16.8 KPa. Heptane is ~6 KPa, octane is ~1.8 KPa, and nonane is ~0.58 KPa. Those three hydrocarbons, and their isomers (which all have similar vapor pressures) make up the super-majority of gasoline. There is some hexanes and pentanes blended in, which have slightly higher vapor pressures than methanol, but these are a small fraction of gasoline, and their blend rates are restricted in the summer BECAUSE of their higher vapor pressures. But now we get back to the topic of toxicity. The exposure limit for methanol is 200 ppm. For pentane the short-term exposure limit is ~1800 ppm, and again concern over pentane vapors sharply limit the blending ratio that is allowed in the summer.
5. Methanol production is growing very slowly in comparison with any other energy related industry. Most methanol sales are in China. The capital cost of converting methane to methanol is quite high, and in Europe methane costs more than methanol on a cost/energy basis.
6. Fuel cells are exorbitantly expensive for a very minor improvement in efficiency, and a serious loss in longevity when compared to a high-efficiency combustion engine. The hype machine has been hard at work for years obfuscating that fact, but it’s fact.
7. China is desperate, they’ll take energy any way they can get it. But renewable methanol will never compete with coal-to-methanol.. so that market is closed for anything other than coal-to-methanol.
8. H2 doesn’t exist in nature. You either have to split water or you have to split methane to get it. If the cost of electricity + amortized electrolyzer costs + amortized chemical plant costs exceeds the cost of coal-to-methanol… you can’t sell renewable methanol to China, and no-one else wants it.
Better to go with non-toxic, higher energy density fuels that have far greater value/unit energy (greater profit).
Glenn,
Thanks again for interesting comments. Let’s go on one at a time:
1)Energy/volume or energy/mass concerning methanol vs gasoline, it’s all the same to me as the spec weight of both is 0.8, i e double in favour of gasoline. You said nothing about my plus for methanol needing less nitrogen-containing air for combustion (thanks half the mass is oxygen) leading to extremely low NOx values in the exhaust. I think double a gas tank is a trifle for a Chinese at the pump, where methanol price (per km range) now is half of gas. However, your wording “double the engine size, double the piston size, etc …” is (as far as I understand) irrelevant in connection with half the energy content of the fuel.
2)You are a Chemist and I am a listening amateur interested and inquisitive in energy all my long life. Still the Boudouard reaction is minimized if the fuel is an oxygenated fuel without C-C bonds and to my knowledge we have only one such liquid at room temperature – methanol. And only one ether – DME (indeed a gas but a liquid at modest 5 bar).
3)I’ve found the same! 🙂 That’s why I am glad to cite Gal Luft: Methanol Blending in China – Trip report (Luft’s study tour on May 21-23 2012 to China’s Shanxi Province to learn about China’s experience with methanol fuel blending): “There have been over 100 million refuelings with methanol. No health problems were observed among the thousands of workers who deal with methanol on a dayly basis and the motorists fueling their cars.”
What about 100 million refuelings with gasoline? ;’)
4)Methanol’s flash point 11 *C, gasoline’s f p -40*C! A methanol fire is controllable with water. Motorsports like methanol for these reasons and for its fine combustion properties in the cylinder.
Back to toxicity. Methanol’s metabolic products formic acid affecting the optic nerve and formate in the blood leading to coma call for security info, info, info. However, general public handles today still worse things!
5) Methanol global consumption has doubled from 30 to 60 Mton in the last six years and is predicted to reach 120 Mton 2020. In absence of pipeline methanol is more and more preferred above LNG/CNG, at least outside USA.
6)Yes, FC may seem obfuscating in many respects, but introduced on the market they may evolve surprisingly quickly.
7)China has sense enough to prepare for a paradigm shift in energy. Why don’t we? They have coal underground. We all have carbon in the sky.
8)Inexhaustible amounts of H2 exists in the sea available by means of renewable energy at high costs. Almost inexhaustible amounts of H2 exists in enormous deposits of methane hydrates (but today we don’t yet know how to use them). Today we get the cheapest H2 from natural gas. Whatever the source we can use H2 for hydrogenating likewise inexhaustible CO2 in the atmosphere into CH3OH. If you want so the petrochemical industry can transform methanol into whatever transportation fuel you like by means of MTG, MTP etc.
We cannot predict the future with certainty, only with probability. I think we can agree on that.
Jan-Gerhard,
I do have patience, but I do not have infinite time. I genuinely appreciate your interest and your passion, but if your purpose is to convince me of the wonders of methanol you must look elsewhere. I’m working on another path that has far more potential. If you are interested in learning, please consider the following carefully prior to responding.
1. The energy content of the fuel has everything to do with the engine size. If you use fuel that has half the energy density, then you have to combust twice as much fuel to get the same amount of energy. A 1.4 L engine today might get ~70 kW of power in a well designed engine burning gasoline… but you’d need a ~2.8 L engine burning methanol to produce the same power. This is elementary math here, but it results in every aspect of the car being more massive, and requiring more massive engine support. If you are driving a vehicle with a ~70 kW engine, you DO NOT want to force the addition of several hundred kg of metal mass onto the car (plus another 36 kg of additional fuel in the larger tank).
NOX is easily catalyzed back into N2 and O2 by passing the gas over a platinum catalyst. Every vehicle in the first world has a catalytic converter – which is nothing more than a chamber with platinum coated balls – to catalyze the produced NOX. NOX is far less dangerous than methanol vapor, and pure methanol engines would still require air-fuel mixing, which means the catalytic converter is still required and the amount of NOX released has more to do with the quality of the catalytic converter than any other factor.
2. Your reply here is not correct, at all. Reaction rates progress based gas concentrations and temperature… but coking occurs during or after combustion, not before… it requires significant heat in order for gasses to coke. The nature of the fuel being burned has very little to do with coking unless there is a pre-heating step (there is not in this case). The Boudouard reaction specifically concerns CO degradation. I don’t care if you have 90% acetylene or 90% oxygen, the only thing that could effect the Bourdouard reaction rate is the amount of CO and the temperature. If you have 90% O2, then there is a great chance of the produced coke re-combusting.. but that is a different reaction.
3. Methanol fuel blending is not pure methanol. We have methanol blended into fuels here in the states… it’s just limited – as is the case with benzene. In small percentages there’s no problem. That’s not “fueling a vehicle with methanol”, that’s using gasoline with a slightly higher level of methanol blended in.
4. Motorsports have luxuries that most people do not – such as an extremely high-compression high-performance engine that costs a million dollars/car. Also, as you noted the incidence of collision in motorsports is much higher per mile than is seen in regular driving, so an unusually high premium is placed on fuels with lower flash point. However, health concerns (and a host of recorded health problems) concerning methanol have long since resulted in methanol being removed from formula 1 racing (NASCAR never had it to begin with)… so now motorsports uses only ethanol, propanol, and butanol – BECAUSE of health concerns surrounding methanol.
5. Petroleum usage is ~4600 Mtons/year, and growing quickly. You’re saying that you hope methanol will grow ~1.25% of the current petroleum market in the next 8 years. I’ll be happy to wager that actual petroleum use will grow far faster than 0.16%/year over that time. Methanol will never be anything other than a minor side-show, easily supplied by coal-to-methanol production.
6. There’s nothing “obfuscating” about the real world price. The price of fuel cells is at least an order-of-magnitude too high to consider under any circumstance. Economy of scale only works if scale happens. Again, I don’t see much demand for methanol developing here.
7. We agree that America is doing nothing to prepare for its coming energy challenges, but ignoring economics is not going to help us find our way.
8. The first step is recovering carbon from smokestacks – as that costs significantly less than separating CO2 from the dilute atmosphere. Hydrogen from water is expensive, and even hydrogen from natural gas is expensive. The product made from that hydrogen must have a higher market value than the cost of the hydrogen, the cost of the CO2, and the amortized capital costs of the system. That is true if you consider renewable synthesis of gasoline, jet fuel, diesel, higher alcohols, and industrial solvents. That is NOT true when you consider methanol – it’s just too cheap of a product to be produced from expensive feedstock, hence it can only be synthesized from coal and still be profitable.
We can assess probability and react rationally. We have to agree on that as well.
🙂
While cutting back on the ethanol component of gasoline has merits during this current drought, we should not lose sight of the goal of maximizing energy efficiency in our fleet of petroleum guzzling vehicles. MTBE was the oxygenate of choice until it was found to be a carcinogen and was persistent in the environment. It did raise MPG by providing a more complete burn in the cylinder. Fortunately at about the same time that we implemented the 10% ethanol standard, we discovered that MTBE was unnecessary afterall since ethanol is just about as effective as a fuel oxygenate. The real problem was the attempt to force the higher percent blends of ethanol which went beyond the point of diminishing returns. MPG drops after just a few percent of ethanol is added.
IMO we should reduce the mandate for ethanol to about 5% which would free up a lot of corn for animal feed and would retain the benefits of an environmentally friendly fuel oxygenate. L
“An acre of U.S. corn yields about 7,110 pounds of corn for processing into 328 gallons (1,242 litres) of ethanol. But planting, growing and harvesting that much corn requires about 140 gallons ( 530 litres) of fossil fuels/gasoline” [equivalent to ~739 litres of ethanol.]
Based on these figures the net energy yield relative to mid US Sunfall (insolation) of about 1,400 to 1,500 KWh/m2/y is about 0.055%, about 200 times worse than PV, and then it’s going to be burnt in a car at about 15% efficiency. This all sounds a bit crazy to me.
Nick, you are completely ignoring the spent mash that is left over after the fermentation process that produces the ethanol. This is a better cattle feed stock than the raw corn. This is rarely included in the calculation when comparing fuel ethanol to gasoline or alternative fuels. Argonne National Labs did a great analysis that makes ethanol a reasonable choice when transportation of the finished fuel product is favorable. It does not transport very well through pipelines.
Some extreme opponents of ethanol for any transportation use will go so far as to chalk up as an energy deficit the sun’s energy that was used to grow the crop of corn. Of course they do not do this for the petroleum that was sourced from ancient plant material that also required solar input. It is comical to see the contortions made by so-called intelligent people who are attempting to prove or discredit a point that they do not agree with. L
You’re right, I was completely ignoring the spent mash that is left over after the fermentation process, but if this is so much better than raw corn as a cattle feed than perhaps all corn for cattle should be treated this way and the ethanol treated as the waste/by product. But to be fair my point was specifically regarding whether producing ethanol from corn, as a supposedly ‘green’ fuel, was a sensible route for capturing solar energy. If we used the acre of land for PV then the electricity it produced would offset about 100 times more carbon than producing corn ethanol, allowing for the fact that powerstations are much more efficient than petrol cars at using energy. So from an environmental standpoint corn ethanol is probably one of the least effective uses of land if CO2 emissions mitigation is the primary reason for growing the crop.
However, the ethanol represents a significant food energy value in the corn which was originally starch. I suspect that the reason spent mash is better for cattle is because its low starch content makes it more similar to grass, cattle’s natural feed and I further suspect there are more effective ways of removing the starch than by fermentation which would retain the starch food content providing better use of the crop.
The most effective use of this land would probably be to use it for growing corn for animal and human food use, with possibly a few percent set aside for solar power generation. What makes corn ethanol the ‘best’ utilisation is economics and market forces which, from all the evidence I’ve seen so far, are unlikely to deliver solutions to our environmental, resource and population challenges without some hefty rigging by the politicians.
Glenn,
Thanks that you spent your time – it wasn’t in vain. Now I understand your outlook on methanol.
Jan-Gerhard Hemming,
Thanks for an interesting discussion. I don’t think we disagree overall nearly as much as we disagreed on the topic of this discussion… and I hope I did not offend you.
Thanks again.
I was preparing a blog that relates to this subject but since this discussion is still going I will post an abbreviated version here. I will post a better version later if I can get the time to complete it.
Note that my original thought about all of this pertained to vegetable oil production for use in diesel vehicles.
First I have noticed that this “discussion” seems to be about using the crappiest feedstock possible grown on the most valuable land to produce fuel for cars that are highly inefficient. Corn seems to be the lowest value feedstock for this purpose. Even sugar beets is a better feedstock for this purpose and the remainder can probably still be fed to livestock. Corn is a lousy food for humans and is better for livestock after being processed for ethanol. Corn is also brutal on the land itself.
Now for my blog.
I drive along a piece of highway in NJ which is 25 miles long. There is at least 50 feet of grass dividing opposing lanes of traffic and 25 feet or more on either side for a total of 100 feet of space around the highway. No matter when I drive this roadway there are large farm size tractors hauling large grass mowing equipment and this goes on constantly during the growing season. So along the length of this road is 303 acres of land. My thought was that it would be wise to use this land for growing fuel crops. Diesel is already being used to mow the grass in this area so fuel usage is likely a wash. According to the quote above, corn yields 328 gallons ethanol/acre. Sugar beets yields about 550 gallons ethanol/acre according to one source I found. I have also found higher numbers for corn to ethanol and lower numbers for sugar beets to ethanol but sugar beets lowest number is still higher than corn’s highest number. So on that 303 acres, using corn, would yield just shy of 100,000 gallons of ethanol worst case.
Now consider the run down I95 from Havre De Grace, MD to Jacksonville, FL which is some 787 miles. Now you are talking 9500+ acres not including the area around on and off ramps at interchanges and so forth. Now we are talking 3.1 million gallons. It is probably possible to increase the margins around the highway by some multiple of the width of the harvesting machinery to gain additional yeild.
If rainwater running off the road were sequestered to use for watering the crops growing alongside the road then yields and crop reliability might be improved.
In more southerly areas it might be possible to get 2 crop rotations per year.
I also thought it might be wise to grow fuel crops right next to the areas where we are emitting the CO2 we are trying to absorb and not on the most valuable land for growing food.
That’s it for now.