Ethanol is Bad. Ethanol from Corn is Worse.
Posted in Econ, Environment, Politics by George
I wrote an article a while ago about the downsides of producing ethanol as a transportation fuel. These downsides, in short, are:
- Ethanol has a negative energy balance. Ethanol from corn, switchgrass, and wood biomass requires 29%, 50%, and 57% more energy, respectively, to create the ethanol than the energy contained within the fuel.
- Because ethanol production requires a significant amount of energy, and most energy in the US is produced from coal, the small reduction in CO2 and other polluting emissions from burning ethanol versus gasoline will be more than offset by the power needed to produce the ethanol.
- Ethanol crops have a notoriously low energy yield per hectare. Thus, it requires a large amount of land to produce a meaningful amount of ethanol. Last year, 20% of the total corn crop was used to produce ethanol, and it offset only 1% of US oil use.
I don’t think that ethanol is a viable fuel of the future unless huge, unlikely technological advances are made. But if we absolutely had to use ethanol, corn is not the biomass we should be using to produce it.
First, corn farming is very hard on soil. It requires nitrogen fertilizer, petroleum-based pesticides, and is very energy intensive (source). Secondly, it also requires a lot of water, water that is in scarce supply in the Midwest, where a lot of corn is grown. Finally, because corn is food, and is an input in the production of many other types of food, ethanol production is driving up food prices all over the US and the world.
Cellulosic ethanol, produced from trees or switchgrass, is a lesser evil. Although cellulosic ethanol production still has a negative energy balance like production from corn, trees and switchgrass are much easier to cultivate. Switchgrass can grow pretty much anywhere, and is harder to kill than corn. In addition, it requires very little fertilizer and herbicide (wikipedia).
I don’t think that ethanol would have so much support from politicians if we were only talking about trees and switchgrass. Corn is the name of the game for many politicians because they’re getting money from corn businesses… why else would a new energy bill support ethanol production from corn when there are better ethanol alternatives out there that avoid many of corn’s problems?
For uncited facts: See David Pimentel’s paper. His paper was published in Natural Resources Research, Vol. 14, No. 1, March 2005, and is entitled Ethanol Production Using Corn, Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower. You can find a short summary of his paper here.
June 18th, 2007 at 12:01 pm
Ethanol has a negative energy balance? Where are you getting these numbers from, the discredited Pimentel study? Every other credible examination shows a 20-60% gain in net energy using current technology and cellulosic ethanol may go beyond this as we learn more about the process and make the production process more efficient. Cellulosic ethanol feedstocks like switchgrass and other native grasses have almost no input requirements, which is why they were growing in the middle of the US for centuries before people arrived to replace them with other plants, and create a _net negative_ CO2 return by locking carbon into the soil through the rot structures.
Corn-based ethanol has many short-term problems that cellulosic ethanol eliminates, but we are never going to have an energy infrastructure in place for cellulosic ethanol unless we prime the pump with corn-based ethanol.
June 18th, 2007 at 12:10 pm
Citations of sources?
June 18th, 2007 at 12:19 pm
Just added citations at the bottom.
June 18th, 2007 at 12:27 pm
The Pimentel study has been attacked by the US Department of Energy, but not in a credible way. They write:
1. He does not assert it takes 70% more energy to grow corn and make ethanol.
2. Very little of his data is old. Most of it is from 2002 or later, and the “old” stuff makes up only about 1% of the total costs he estimates.
3. He explicitly gives credit for the animal feed co-product of making ethanol.
4. Anyone think the Nat’l Corn Growers Association might be a little biased?
I still don’t believe that switchgrass-based or any type of ethanol will be the transportation fuel of the future. Switchgrass may not be as bad as corn, but the technology needs to dramatically improve before it is a viable option.
Another interesting point is that plants capture something like 0.1% of the sun’s energy, whereas photovoltaics capture around 10%. This really makes me feel that electric vehicles, once batteries are developed further, could make a huge difference in reducing our oil dependence.
June 18th, 2007 at 1:02 pm
What you need to look at is ethanol from sugar vs from corn. You will find that ethanol from sugar is more efficient, but with the USA’s tariff on sugar cane imports it dose not make it cost efficient.
June 18th, 2007 at 1:06 pm
I don’t understand. All forms of fuel production require more energy input than is ultimately made available by the fuel itself. That’s the Second Law of Thermodynamics in action.
If producing ethanol from corn requires only 29% more energy than is contained in the fuel, well, that’s not all that bad. Just as oil refineries can be powered by part of their oil production, the process of converting corn to ethanol can be powered by part of the ethanol production. (Of course, it may be better in practice to provide this power from some other source, since the goal of the ethanol production is to provide fuel for motor vehicles. I find it a little strange that natural gas seems to be the preferred energy source for this conversion, since natural gas can be used directly by motor vehicles, and there’s no shortage of the stuff just yet.)
Based on the numbers presented here, energy efficiency is not a good argument. However, I think the other arguments– the environmental costs of corn farming and the effect on the food market– are persuasive, and I agree with the conclusion that ethanol from corn is not a good fuel source today.
Once oil production begins to decline, however– whether you believe that has already happened, will happen soon, or will not happen until 2050 or later– we’re going to need alternative fuel sources. That means it’s probably a good idea to start collecting data on full-scale production processes. If we’ve learned enough about turning corn into ethanol, let’s move on to switchgrass and whatever other sources seem attractive.
. png
June 18th, 2007 at 1:38 pm
Why so many people writes more than read, it’s the equivalent of talking more than earing.
In Brazil ethanol was used for more than 20 years as a car fuel and have a lot of producers without government subsides having lot of profits.
Sure it takes more energy, but until someone doesn’t change thermodynamics laws it will stay as it is.
Try search sugarcane ethanol or alcool.
June 18th, 2007 at 2:22 pm
The Pimentel results have been discredited by more than just the DoE. His claims regarding the lifecycle costs for ethanol production were shown to be wildly inaccurate and horribly out of date. His claims regarding ethanol production efficiency have also been shown to be BS.
Take a look at the MSU studies for counter-examples.
June 18th, 2007 at 2:59 pm
@Someguy & Someone:
I agree that ethanol from sugarcane is more efficient than corn. However, the US can’t emulate Brazil’s ethanol success because of two factors. First, to grow sugarcane, a warm climate is needed, and much of the US is too cold to grow it. Secondly, Brazil’s total fuel demand is very small compared to the US in per capita and aggregate terms, so much less land is needed to grow fuel. US Transportation fuel demand is huge in both aggregate and per capita terms. This coupled with the fact that very few areas of the US are suitable for growing sugarcane make it a less viable option.
@evgen:
I’ve looked at Pimentel’s results myself and I completely disagree with the claims that his results are invalid. They’re all relatively up to date and the claims his critics make are just simply untrue. Most of the critics claim that he uses “old” data. I encourage you to take a look at his paper and calculate how much of his data is “old” and how much the old data could affect his results. From my reading of his paper, I found that old data made up a very small portion of his data and made very little effect on his overall results.
I’ve seen some counter examples but they do not cite all of the steps of the production process from corn all the way until ethanol. Pimentel’s work actually takes into account every single step from corn to fuel.
June 18th, 2007 at 3:10 pm
Peter G, you are confused. All fuels don’t take more energy to produce than is received. You are misunderstanding the second law of thermodynamics.
Oil exists already as fuel. It’s transported and purified to gasoline, which takes some energy but not more than what the gasoline provides. People put in X amount of energy into transport and purification and receive X+Y back.
Ethanol, on the other hand, requires Z amount of energy to convert the plant matter to fuel and they receive Z-W back. Between farming the plant matter, processing the results, and transporting it, it costs MORE in energy than it provides.
June 18th, 2007 at 4:39 pm
Pimental is up to date? Do you mean the corn production statistics he uses from 1992 or the ethanol production efficiency numbers that are from the mid 90s? I can see that you have already made up your mind and will gravitate to the studies that support your view, but you should perhaps stop and ask yourself why it is that the Pimentel study is the aberrant data point when compared to all other ethanol studies.
Argonne National Lab 2005: 35% net gain from ethanol
USDA 2004 (update of 2002 study): 67% net gain
Univ. of Minnesota: 34% net gain
Michigan State University 2002: 56% net gain
Since 1995 there have been nine widely examined studies that have shown ethanol to be a net gain of some degree and only _one_ study that shows a net energy loss. I guess you think that the study by the entomologist is more credible than ones from chemical engineers and agricultural scientists…
If you really want some good references to critiques of Pimentel’s “research” along with references to studies that show the various mistakes/deceptions in Pimentel’s papers I suggest you poke around Journey to Forever for a bit.
June 18th, 2007 at 5:42 pm
If you add in all the energy and costs to fight wars to get oil. Ethanol is far cheaper. Everything is cheaper that does tranfers wealth to terrorist states that have oil. Wake up all you ethanol haters.
June 18th, 2007 at 6:02 pm
Sorry, but that data is not only old, but horribly wrong. The net output for switchgrass ratio is 4:1, making it a 300% net gain. Do some more research before you start posting old inaccurate data.
Quote:
“Sugarcane, at 1:8, yields about eight units of energy for every one unit invested to grow, harvest and convert the cane into ethanol. The fibrous cane material that remains after the sugar has been extracted (also known as bagasse) is used to provide heat (read: energy) in the distillation process. In most cases, this eliminates the need for energy from an external source. One unit of energy is used for every five units provided by the Miscanthus-based ethanol fuel. Switchgrass’s net energy yield is slightly less, at about 1:4. Sugar beets yield nearly two units of energy for every one unit that is used to grow and convert the crop into ethanol. Corn lies near the very bottom of the list at 1:1.4.”
Source: http://www.cleanhouston.org/energy/features/ethano...
June 18th, 2007 at 6:40 pm
Corn ethanol is indeed VERY bad.
Sugar cane ethanol is quite good and unlike the US, Brazil has HUUUUGE amounts of free land to grow it.
That’s why it scares the shit out of Americans…
June 18th, 2007 at 6:56 pm
Hemp.
June 18th, 2007 at 9:36 pm
Sorry, but I just want to clear up a misconception about the second law of thermodynamics. Of course more energy is put into producing fuel than the energy that comes from the fuel, but in fossil fuels and other kinds of fuels the energy ultimately comes from the sun. We do nothing to store up potential energy in those fuels. What George is talking about is the energy put into making ethanol usable, which requires other fuels to be expended. The energy that is utilized from passive exposure to the sun is not taken into consideration; only the energy used in processes carried out by humans is taken into consideration. I’ve hear this as being a problem for Hydrogen fuel. If you have to burn more fuel to organize hydrogen into hydrogen cells than then energy that comes out from the hydrogen cell, then it’s pointless.
June 19th, 2007 at 12:10 am
I agree, ethanol is not the future. neither is hydrogen. both are too expensive. I believe that the cost of photovoltaics will come down and that solar energy is the future. as for batteries, we won’t need them if transport is accomplished with a dualmode system, where vehicles will travel large distances on rails or a guideway and the final short distances conventionally on roads.
June 19th, 2007 at 12:48 am
Oil production has had how many years to squeeze every penny of profit out of the business?
Ethanol might not be the best source, but from the amount of fertilizer being slung around here, we could have grown another years crop.
Bottom line, we have to start somewhere, nobody took the black sludge out of the ground, put it in their car and started driving around on it, it takes time to invent the technology to replace fossil fuel. The steam engine was not very efficient, nor is the petrol.
Where do we go next? Electric cars have to overcome their own weight and limited distance, not to mention that the cost is around $100K for each new model, vs ethanol enriched fuel being added to your old car’s gas today. The real replacement has to overcome friction, which right now is still using grease from fossil fuels.
June 19th, 2007 at 4:44 am
@ realist:
Absolutely. I am sick of reading all of the same old arguments that ethanol is a terrible idea, will never work, is net energy negative, etc. Just as you said, these things take time to develop - There will be problems in the beginning, but where there is money to be made, the market will find a way make it in the most efficient manner possible. Farmers will find a way to increase yields, ethanol producers will find ways to extract more ethanol from the crop, and auto makers will begin churning out high octane engines to take advantage of ethanol’s 113 octane rating. In two years, we’ll all be running on 10% ethanol. When cellulosic ethanol becomes economically viable, the real boom will begin. I don’t know where the author got his information, but ethanol produced from switchgrass contains 10 times the energy needed to produce it. And that’s today, before the 70 years of technological advancements that gasoline has. It’s obvious that oil is nonrenewable, and eventually, it WILL run out - So why not begin planning for the future now?
June 19th, 2007 at 12:45 pm
There have been plenty of criticisms of Pimentel’s paper, but I really encourage you to look at the data yourself. I just created a spreadsheet with all of Pimentel’s data and the dates he gets in from. I calculated what would happen to his calculations if any data before 1999 were eliminated (i.e. energy cost disappeared, making his result weaker) or was only 50% as high. The result? See for yourself on my excel spreadsheet.
In short, I found that even if his old data or data without a source were replaced with only 50% of its reported value, corn based ethanol would have an energy balance of -17%. Replaced with a zero? Still -13% balance.
Read Pimentel’s Paper in question here to decide for yourself.
June 20th, 2007 at 2:31 am
i agree with the author, corn is NOT a good idea for biofuel. Without wanting to sound like a pot head hemp would be a more appropriate source of biomass fuel.
1. Hempseed oil has a complex polymer structure.
2. Hemp is a resting crop
3. Hemp grows crazy high and dense with very little effort.
4. Hemp can have from two to four growing seasons a year
5. a lot of the fiber can be left to decompose on the field returning and enhancing the soil it came from
6. hemp is naturally antibiotic and resists most pests and disease
HEMP FOR VICTORY!!!!
June 20th, 2007 at 7:51 am
Hemp has always sounded interesting to me, but I feel in terms of energy balance, hemp would be worse off than some other fuels, because it’s difficult to process something with a lot of fiber.
But hempcar.org looks pretty cool.
June 20th, 2007 at 1:01 pm
You’re poorly informed.
August 22nd, 2007 at 11:29 pm
I agree, i think ethanol is a HORRIBLE thing to be producing and never should have been created and should stop producing it now! We will all be severely for this in the future! It will drive up prices on many things that have anything to do with corn whatsoever! Milk prices are already around $5.00 a gallon, and I blame it on ethanol! Milk comes from cows, and cows eat corn, so therefor higher corn prices=higher feed prices=higher milk costs! Cheese is made from milk so everything that has anything to do with cheese will go up! land prices are going up.. corn is grown on land! There will be more corn grown and less soybeans, which means less soybeans available, which means soybean products will go up in price! Prices on everything will skyrocket! Another thing, I heard that if we used EVERY bit of corn in America, that it would only cover about 16% of our fuel needs! Then we also need corn for animal feed, our food, and it’s used to burn for heat. We cannot produce near enough corn to make ethanol anywhere near worth producing, and ethanol isn’t that much cheaper than regular gasoline. We will be spending MANY more times amount of money of food and everything then we would be saving on fuel, it’s going to kill the economy! Ethanol production uses thousands of gallons of water, it’s recycled, but still a lot of water is needed. So I think America needs to boycott ethanol all together and we need to find some other source of energy for our vehicles, how about electric?? Corn is not the answer!! The ONLY people who will benefit from this is the farmers themselves.. everyone else will SUFFER from it in the long run!
August 23rd, 2007 at 4:31 pm
Thank you, Adam Smith.
October 17th, 2007 at 1:59 pm
Thank you for your coments
November 16th, 2007 at 9:43 am
I’d agree. Ethanol is not our saviour. We need to look at other alternatives.
Check out: http://fourreasonswhy.com/2007/11/16/big-ethanol-i...
December 7th, 2007 at 10:14 am
[…] to do something to help? Boycott ethanol. You be saving the Planet. And a whole lot of water. And that’s a good […]
January 26th, 2008 at 8:07 pm
“Switchgrass grown for biofuel production produced 540 percent more energy than needed to grow, harvest and process it into cellulosic ethanol, according to estimates from a large on-farm study by researchers at the University of Nebraska-Lincoln.”
http://www.sciencedaily.com/releases/2008/01/08010...
April 2nd, 2008 at 10:08 am
Does anyone else see a huge moral problem with turning food into fuel for cars and such? There have been food riots now in China, Paskistan and Mexico because were driving the prices of staple foods up by developing ethanol. Whats our new motto over here? Drive a truck starve a Mexican?
April 2nd, 2008 at 12:51 pm
That goes hand in hand with the fact that if every person in the world lived the lifestyle of the average American, civilization would be destroyed because we don’t have enough natural resources to provide the American lifestyle to everyone.
The whole ethanol business takes this one step further.
And the hypothesis of civilization collapse may be tested sooner rather than later with the Tata Nano, the $2,500 car that will be sold all over India and many developing nations thoughout the world in the near future. Can we handle billions of new drivers?
If you’re worried about gas prices now, get ready for a real surprise in the near future.
April 17th, 2008 at 11:22 am
I also am a HUGE believer that ethanol is a BAD way to go for this country. The amount of corn needed to produce a tank full of ethanol for a suv would feed someone for a year. How stupid are we? Lets make our food prices out of sight and less available for something that does nothing. Also if a tanker of ethanol spills and catches most fire stations dont have the right chemicals to put out the fire. It does nothing towards fixing our dependence on foreign oil. We need to develope either hydogren engines or biodiesel fuel from organic material other than food supplies. Also drill in alaska and use that oil until the alternate fuels are better perfected. Better to pay alaska for oil then the arabs that want us all dead. No good can come from ethanol and I wish people would realize this. BAD NEWS!
April 27th, 2008 at 1:12 pm
On average, E85 is only about 20 cents cheaper then regular gasoline. Take away the 51 cent subsidy taxpayers are handing over to ethanol producers plus the subsidies from each individual state, you will be paying more for E85. Even with crude around $100 per barrel, gasoline would be cheaper. Don’t forget about how much you will pay for anything else corn related. High fructose CORN syrup anyone?
April 27th, 2008 at 1:18 pm
@Adam: Thanks for the comment. Don’t forget about all the animals that are fed by corn. Meat and milk prices are rising as well, as corn is an input in their production process. Ethanol production is driving up food prices across the board.
With the food shortages in the world today, and the fact that many poor consumers can’t buy enough food to survive due to the higher food prices, today’s ethanol policy is not only stupid, it’s unethical.
May 3rd, 2008 at 5:31 am
It’s not the Kyoto greenhouse myth that’s the issue, really, so much as it is the global food shortages that we feed our gas-hog cars the food we’ve ripped from the mouths of orphans. I’d say boycott ethanol, especially corn ethanol, if it was possible for any average citizen to do so.