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The Almighty Buck United States Science

The Strange Energy Budget of Ethanol Production 200

joeflies writes "The San Francisco Chronicle published an article regarding research on how much fuel is required to make Ethanol. The results indicate that it make take 6 times more energy than the end product delivers."
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The Strange Energy Budget of Ethanol Production

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  • by 1967mustangman ( 883255 ) on Monday June 27, 2005 @05:13PM (#12925115)
    Ethanol has long been a problem. The real insteresting prospect is the company up in Canada that is creating ethanol from the woddy portions of plants with a genetically modified bacteria see this slash dot story http://science.slashdot.org/article.pl?sid=05/01/0 7/1846247&tid=14 [slashdot.org]
  • Re:Hmm (Score:3, Informative)

    by TykeClone ( 668449 ) * <TykeClone@gmail.com> on Monday June 27, 2005 @05:19PM (#12925190) Homepage Journal
    According to TFA, they are including the energy used in producing the fuel used for growing and harvesting the grain and for making the fertilizers. This should probably be backed out of the equation because these activities will take place anyway - regardless of whether or not we're using ethanol.

    The TFA also disregards the uses of the rest of the byproducts of ethanol production (distillers grain and industrial gases).

    The useful thing about ethanol and biodiesel is that we already have an infrastructure available and ready to use it as a vehicle fuel now. With Hydrogen fuel we don't. Same with Fuel Cells.

  • Re:comparisons? (Score:5, Informative)

    by kherr ( 602366 ) <kevin@puppe[ ]ad.com ['the' in gap]> on Monday June 27, 2005 @05:28PM (#12925278) Homepage
    Minnesota Department of Agriculture has a comparison of energy costs [state.mn.us] to produce different types of fuel. Treat this as a starting point for information.

    People seem to forget that we don't pump oil out of the ground and into our gas tanks, it requires some serious refining. I've also heard that ethanol processing essentially removes the sugars from the corn, leaving a high-protein slurry that can be used as animal feed. Since it's high in protein and low in carbohydrates it's a more efficient feed and causes lower emissions from the cows. Heh.
  • Re:comparisons? (Score:3, Informative)

    by WhiplashII ( 542766 ) on Monday June 27, 2005 @05:38PM (#12925376) Homepage Journal
    How it really works is this:

    Scenario A: You dig up 1 barrel of oil. You burn the oil, VROOM-VROOM!

    Scenario B: You dig up 6 barrels of oil, you use the oil to make 1 barrel of Ethanol, VROOM-VROOM!

    What the article is saying is that wasting 6 barrels of oil to create one barrel of ethanol doesn't make any sense. And they are right - though you can argue whether their study is more valid than the USDA study which stated the opposite. I would look at the relative biases (the USDA gets money if they say ethanol is good), and look at the differences in the numbers (the USDA study did not include maintenance on the equipment, etc.) to see which one to believe.

    Personally, I think the truth lies somewhere between the two - but is probably a net negative. Plants are horibly inefficient solar cells! (If it was simple, we would be burning trees instead of oil!)
  • by TykeClone ( 668449 ) * <TykeClone@gmail.com> on Monday June 27, 2005 @05:43PM (#12925438) Homepage Journal
    That's gotta come from somewhere, and right now its going to be fossil fuels.

    Fossil fuels != oil. Coal can be (and is being) used to fire ethanol plants. We have a larger supply of coal readily available - in the United States - than oil and essentially converting it to a liquid fuel (in the form of ethanol) would be useful for weaning the economy off of foreign oil.

  • Re:Hmm (Score:3, Informative)

    by jcorno ( 889560 ) on Monday June 27, 2005 @05:44PM (#12925447)
    According to TFA, they are including the energy used in producing the fuel used for growing and harvesting the grain and for making the fertilizers. This should probably be backed out of the equation because these activities will take place anyway - regardless of whether or not we're using ethanol.

    No, they won't. Farmers don't grow corn they don't intend to sell, and manufacturers don't make fertilizer they don't intend to sell. Both have increased production expressly for this purpose. Without the ethanol market, the farmers would cut back to keep prices under control. Same for the fertilizer.
  • by brandido ( 612020 ) on Monday June 27, 2005 @06:12PM (#12925901) Homepage Journal
    It is too bad that the person who wrote the title didnt bother to RTFA:
    Shapouri's most recent analysis, which the USDA published in 2004, comes to the exact opposite conclusion of Patzek's: Ethanol, he said, has a positive energy balance, containing 67 percent more energy than is used to manufacture it. Optimistic that the process will become even more efficient in the future, he pointed out that scientists are experimenting with using alternative sources like solid waste, grass and wood to make ethanol. If successful on a large scale, these techniques could drastically reduce the amount of fossil fuel needed for ethanol production.
    The analysis showing that Ethanol uses more energy that it produces is based on outdated farming and processing techniques. Using modern techniques, it is energy positive.
  • by Passman ( 6129 ) on Monday June 27, 2005 @06:27PM (#12926043) Homepage Journal

    I agree, this did smell funny. So I went out and did some research.

    It seems that the "scientist" in this story, Tad Patzek (a geologist), has been working for the oil industry quite a bit over the last [lbl.gov] few [berkeley.edu] years [ilcorn.org]. Odd that he should suddenly be switching his interest to agriculture and begin attacking Ethanol.

    Or perhaps it all makes sense if you look at it from the correct prospective.

  • by gregor-e ( 136142 ) on Monday June 27, 2005 @11:50PM (#12928473) Homepage
    Here's [64.70.252.93] a Cellulosic Ethanol Fact Sheet that claims cellulosic ethanol can be created for an oil-equivalent-cost of $13/barrel.
  • by bluGill ( 862 ) on Monday June 27, 2005 @11:53PM (#12928488)

    1: This is more complex than is seems. Ethanol has less energy than gasoline. (~70BTU vs ~109BTU) However ethanol is also about 108 octane (pump gas is 87-92 depending on the grade). If you assume you will never run on gas you can increase the compression, and get almost as much useable energy out of ethanol, even though your input is less.

    No. It will be less (even if you up the compression as I suggested above). However even with standard compression, ethanol burns more efficient than gas, so it won't be 30% less. This assumes that your car was designed to run ethanol. If it wasn't your mixtures will be wrong, and you will blow your engine before you get statistically valid results.

    3: I'm not sure. I think less, but I don't know. Gas is pretty volatile itself, and its vapors are more harmful.

    4: They are close enough.

    5: Not really. Oil for many years was cheaper. In the 1890s gasoline was a byproduct they dumped into the lakes to get rid of (litterally), after separating it from what they wanted. Gas engines were designed to use that waste. Henry Ford designed the model T to use ethanol, but gas really was that much cheaper then that it didn't make sense. Gas is more expensive now (and we know about the environmental effects), so it is time to revisit ethanol.

    6: Right now the ethanol market is glutted, and farmers are building more plants. You can assume that if more people used it prices would go up. I estimate that the entire US could move to 25% ethanol over the next 10 years, with little effect on price. Farmers build ethanol plants because they don't need to make money on the plant, so long as they don't loose too much. The additional market for corn makes up for it. Not to mention they need more high protein animal feed, which is a byproduct of ethanol production. 25% ethanol would be enough that the US could stop all imports from OPEC.

  • Re:This is flawed. (Score:3, Informative)

    by jfengel ( 409917 ) on Tuesday June 28, 2005 @02:25AM (#12929103) Homepage Journal
    Sugar beets produce ethanol, not biodiesel. Same gist (non-petroleum fuel) but different engines.

    Also: Brazil isn't really a big cocaine producer. Brazil imports its cocaine from Peru. I honestly can't tell you why there isn't a big home-grown cocaine industry in Brazil.

    Sorry for being pedantic. Your ultimate point is actually a solid one: "Hey, farmers around the world, maybe you can make more money growing fuel than growing drugs." Wouldn't that be nice? I dunno if it works out economically, but it's certainly worth research.

Mystics always hope that science will some day overtake them. -- Booth Tarkington

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