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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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  • comparisons? (Score:5, Insightful)

    by TheClam ( 209230 ) on Monday June 27, 2005 @04:00PM (#12924967)
    Compare this to gasoline and hydrogen and you've got yourself a real article.
    • in the fourth paragraph the article says:

      "The fossil energy expended during production alone, he concluded, easily outweighs the consumable energy in the end product".

      so that base is covered. ethanol is just a way to keep some farmers in business. it does cut down on smog too. but at what price?

      • Bullshit, just use *naturally* supplied energy and put the processing plants where this energy is available. A la, hydroelectric dams (northeast?), solar farms (southwest), wind farms (oklahoma), and do the processing there. We have a choice locally to use *clean* electric for a slightly higher fee, so why not use renewable energy resources to generate ethenol?

        Maybe people are over reacting. Solution seems logical to me, any different ones?
        • that sounds like a good idea. dont over react. under the current system it uses too much fossil fuels to generate ethonal. thats all i (and the article) was saying, not that it is the only way to produce ethonal. i dont know of any electric powered heavy farm equipment yet. do you? is anyone researching that avenue?
    • I was about to say the same thing.

      "(Ethanol production) may eat up far more energy during its creation than it winds up giving back."

      Ok, sure, I won't dispute the findings. Ethanol gets us a 1/6 return in energy while with fossil fuels we get what return for investment? What's that, zero! You gotta be fucking kidding, me. When did zero become better than one sixth? How many investors would spend money on something guaranteed to not have any return on their investment over the possibility of getting 1/6th

      • Re:comparisons? (Score:3, Informative)

        by WhiplashII ( 542766 )
        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
        • Nitpick 1: Ethanol contains less energy than oil per unit volume.

          Nitpick 2: The value of energy from plants doesn't have anything to do with their efficiency as solar cells. Any inefficiency is more than made up for when you consider that the things manufacture themselves.
    • Re:comparisons? (Score:5, Informative)

      by kherr ( 602366 ) <kevin&puppethead,com> on Monday June 27, 2005 @04:28PM (#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.
      • '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.

        It's called distillers grain and (interestingly enough), it has its own website: http://www.distillersgrains.org/ [distillersgrains.org]

      • Summary - Energy Balance/Energy Life Cycle Inventory

        Fuel Energy yield* Net Energy (loss) or gain

        Gasoline 0.805 (19.5 percent)
        Diesel 0.843 (15.7 percent)
        Ethanol 1.34 34 percent
        Biodiesel 3.20 220 percent

        * Life cycle yield in liquid fuel Btus for each Btu of fossil fuel energy consumed.
      • Re:comparisons? (Score:3, Interesting)

        by RevAaron ( 125240 )
        Speaking of cows- if people were so darned concerned about how much energy is spent producing another form of stored energy, then they wouldn't each so much damn beef and other meat. From this site: [britishmeat.com]

        Conservation of Fossil fuel. It takes 78 calories of fossil fuel to produce 1 calorie of beef protein; 35 calories for 1 calorie of pork; 22 calories for 1 of poultry; but just 1 calorie of fossil fuel for 1 calorie of soybeans. By eating plant foods instead of animal foods, I help conserve our non-renewable

        • There was an article in Harpers a while back about the cost in fossil fuels of our agricultural system. Scary stuff--basically, Peak Oil means drastic increases in food prices. Not only do you have the effect of massively increased transport costs, but the materials used to fertilize the crops become much more expensive too.
        • just 1 calorie of fossil fuel for 1 calorie of soybeans. By eating plant foods instead of animal foods, I help conserve our non-renewable sources of energy.

          If there was ever an argument to get me to go veg*an, that'd probably be it.


          No reason to be exclusively vegetarian either, if you're not doing it for ethical reasons -- simply shifting to a mostly vegetarian diet can yield a lot of benefit.

          [My mom used to buy "soy extended" hamburger meat when I was a kid, for budgetary reasons, but I absolutely love
        • If god didn't want us to eat animals, why did he make them so tasty?

          On a more serious note, it would make a lot of sense to seriously cut down on the amount of meat we eat for more reasons than just the amount of energy it takes to grow it.
    • It's all dependent on which stage of the energy cycle you focus on. Imagine the amount of efficiency in coal energy:

      1) Sun feeds plant production (very inefficient)
      2) plants die, form coal
      3) Coal is burned (again, very inefficient)
      4) Heat from coal boils water, powers turbines (Oh you'd better believe that's inefficient)
      5) electricity from turbines goes into power grid to homes (lots of loss there)
      6) electricity powers computer (inefficient) belonging to slashdot reader at work (inefficient)

      Besides, as fa
    • Compare this to gasoline and hydrogen and you've got yourself a real article.


      A real article? Obviously you didn't read the original post. It's an article from the San Francisco Chronicle. For those of you outside of San Francisco, the Chron is a collection of press releases and marketing hype punctuated by the occasional column about some guy's cats. "Real" articles will only be found in real newspapers.
  • I read that as, it will cost you more in the end; if you think prices are high now, just wait..!
  • by 1967mustangman ( 883255 ) on Monday June 27, 2005 @04:13PM (#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]
  • ... the sooner we get off of our reliance of fossil fuels, the better off we'll be.... we need to focus more research efforts on improving our superconductor technology!

    Currently we're far too low to be useful in an every day sort of way (around -211 deg. F I think) ... but the higher this goes, the more uses it has.

    [Lower energy loss means longer energy storage and more effective energy generation]

    ===

    Fossil fuels are fossils, its time to move on up!
  • the advantage of ethanol isn't that it's more efficient than gasoline, or cleaner -- the adantage is that it's a drop-in replacement fuel for most internal-combustion engines that now burn gasoline.

    sure, as long as there's oil, ethanol doesn't really look efficient or affordable except as a fuel oxygenator. but if the oil reserves were to run out sometime soon, ethanol could be poured into most of our existing infrastructure and ease the transition. that's why it's important -- not because it's inherently s

    • by Mr.Sharpy ( 472377 ) on Monday June 27, 2005 @04:39PM (#12925388)
      sure, as long as there's oil, ethanol doesn't really look efficient or affordable except as a fuel oxygenator. but if the oil reserves were to run out sometime soon, ethanol could be poured into most of our existing infrastructure and ease the transition. that's why it's important -- not because it's inherently superior to petroleum, but because it can be manufactured (from scratch) much more quickly.

      Did you even read the article? You're missing the entire point! If the oil reserves run out you won't be able to get any ethanol to pour in your car either! Corn based ethanol requires far more energy in its production than it is capable of producing itself, almost all of which comes from fossil fuels. In fact, according to this article producing one unit of energy in ethanol requires 2.3 units of energy to produce. That's gotta come from somewhere, and right now its going to be fossil fuels.

      The bottom line is that ethanol programs are, right now, nothing more than another farm subsidy. The politics such programs are beyond the scope of this article, but suffice it to say that touting ethanol as the solution to our energy problems is at best disingenuous, dishonest, and a potentially disasterous diversion from the real technologies we are going to need to maintain our current life styles in the future.
      • 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.

        • True, but, you should investigate what happens in coal mining operations. It ain't pretty, and I'd rather have an oil derrick around than have a nice mountain stripmined for the layer of coal.
        • Coal can be (and is being) used to fire ethanol plants.

          True, but I'd be very surprised if it weren't more efficient to produce synthetic oil [americanen...ndence.com] directly from coal, rather than burn the coal to fuel the farming and distilling operations needed to produce ethanol.
      • Ethanol production from corn, you mean. If you use sugarcane as feedstock, there is a significant net energy outcome.

        A more thorough article has been http://petroleum.berkeley.edu/papers/patzek/CRPS41 6-Patzek-Web.pdf> published by Mr. Patzek. It could also be argued that he is considering only the current practices in american industry. If best practices were adopted, the results would surely change somewhat.
    • What in the blazes are you talking about?

      Where do you think your going to get this ethenol during an energy crisis? If it takes 5 gallons of refined oil to make 1 gallon of ethanol your still going to run out of oil to make the ethenol. And when you switch to ethenol as your power source to grow the ethenol, you'll run out of energy even faster.
  • This is flawed. (Score:5, Insightful)

    by EvilMagnus ( 32878 ) on Monday June 27, 2005 @04:19PM (#12925191)
    "Taking grain apart, fermenting it, distilling it and extruding it uses a lot of fossil energy," he said. "We are grasping at the solution that is by far the least efficient.".

    He ignores the fact that, if we wanted to, we *could* arrange the production chain so that it was not dependent on fossil fuel. You could build your farming and fermentation facilities to use solar or hydro power, for example.

    Sure, it's fossil-intensive *now*. But it's also not a major energy source yet. If we needed to we could clean up the energy chain - there's no part of the process that requires fossil fuel sources.
    • Still, why do it at all? If you use solar or hydro power to create six times as much energy as the ethanol produces, why not use that energy instead?
      • The problem with most energy expecially solar and to an extent hydro you have to use it right away. with this you get to keep it for effectivly as long as you'd like. I'm sure it has a shelf life but it is transportable and useable in a realistic way.
        • A much more efficient method of storing large amounts of energy is "pumped hydroelectric energy storage". This is simply conversion of electricity to gravitational potential energy by pumping water from a lower reservoir to a higher one while excess energy is being generated by another source (e.g. solar), and converting the gravitational potential energy back into electrical energy when it isn't (e.g., at night). With modern designs, the generator simply is used in "reverse" to act as a pump.

          This proce

      • Because you can't take the waterfall with you, and the sun doesn't shine at night. :)

        The energy must be stored somehow for use on demand. Putting it into a combustible liquid is one way. Putting into a battery is another - although at the moment the process of making and disposing of the batteries is very environmentally unsound.
    • Re:This is flawed. (Score:3, Insightful)

      by DerekLyons ( 302214 )

      "Taking grain apart, fermenting it, distilling it and extruding it uses a lot of fossil energy," he said. "We are grasping at the solution that is by far the least efficient.".

      He ignores the fact that, if we wanted to, we *could* arrange the production chain so that it was not dependent on fossil fuel. You could build your farming and fermentation facilities to use solar or hydro power, for example.

      And you ignore the fact that regardless of the energy source, ethanol is *still* a net sink of energy

      • Re:This is flawed. (Score:5, Insightful)

        by WolfWithoutAClause ( 162946 ) on Monday June 27, 2005 @05:21PM (#12925992) Homepage
        Nah. The real point behind all this is that in USA they make ethanol from corn, because they grow a lot of corn, and powerful lobbies have introduced a huge subsidy to use that source of ethanol to try to keep the cheap biofuel from Brazil off the market.

        Of course the Brazilian biofuel comes from sugar beat and so forth, which actually is somewhat efficient and gives a net energy win; which is why Brazil have been able to run lots of their cars on it for quite a while now.

        So what this paper is really saying is not that biofuel is a waste of time, but that 'The American Government are morons' with their stupid corn-based ethanol subsidy. But you knew that already, unless you're a corn farmer.

        • Exactly.

          The same reason we use high-fructose corn syrup for sweetener instead of sugar cane like the rest of the world. :)

          It's a fixable problem, but we may have to endure a few years of the Brazilians laughing at us while we all push our cars to work for want of fuel.
        • Hm, how much does biodiesel from sugar beat earn per square metre per year, and how much for cocaine? Maybe buying lots of biodiesel from Brazil could reduce the drugs trade.
          • Might work, particularly if you deliberately arranged for the US government's sugar beet price equal to, or above that of the cocaine.

            Of course it would be rather open to abuse- I could rather imagine people from all around the world selling their sugar beet to Brazil; and them selling it on to the US government... :-)

            Still, if you tied the buy quota to the size of the farmers field you'd do ok, together with spot checks (satellite?)

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

            by jfengel ( 409917 )
            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'
      • And you ignore the fact that regardless of the energy source, ethanol is *still* a net sink of energy. *Regardless of the energy source*.

        Well, duh.

        I'm not ignoring it - I know that energy is lost in state changes. But as I just pointed out to someone else, it's not the loss that's a bad thing - it's because the original Source of All our Energy, the Sun, doesn't shine at night.

        We can't use solar or hydro power everywhere. We have no portable nuclear reactors for our Atom Cars. So we must used stored ene
  • "If government funds become short, subsidies for fuels will be looked at very carefully," he said. "When they are, there's no way ethanol production can survive."

    Right there the article ignores the politics surrounding ethanol. The politics surrounding other energy sources/storage mechanisms don't have the power that ethanol backers do.
  • The study referred to in the story was published [tandf.co.uk] last year in Critical Reviews in Plant Sciences [metapress.com]. Abstract free, the article, like most journal articles, is probably very expensive.
  • by WolfWithoutAClause ( 162946 ) on Monday June 27, 2005 @04:25PM (#12925236) Homepage
    If it takes 6x as much energy to produce it, you would expect that it would cost more than 6x as much than the original fuel. So far as I'm aware it doesn't, nothing like. Ethanol costs about $1.50 a gallon... Compare that with the cost of gasoline for example; or aviation fuel (last time I checked, about $1/gallon- slightly cheaper).

    Also, they've been making ethanol for vehicle fuel in Brazil for years... if it was so very uneconomic I wouldn't expect them to do that.

    As in, what gives? I smell politics.

    • did you forget that ethanol production is subsidized by the feds?
      • Did you forget that 'the feds' don't actually own Brazil? Doesn't look like Brazil has any problems having to produce biofuel with a net deficit of energy.

        Looks like they grow sugarcane and other plants rather than corn, presumably grows slower, but it's probably easier and less energy intensive to process.

        • Actually, the ethanol industry in Brazil is also heavily subsidized by their government (the programme is called "Pro-Alcool" if you want to google...).
      • 54 cents per gallon of ethanol, 5.4 cents per gallon of 90/10 blended gasoline. Did you forget that the oil industry is also subsidized by the feds?
    • by linuxwrangler ( 582055 ) on Monday June 27, 2005 @05:05PM (#12925802)
      I smell politics.


      Good nose. And when the politicians are bought and paid for by Archer Daniels Midland [admworld.com] and friends the result is government subsidies for corn-derived ethanol and a full-court press to keep Brazilian ethanol (sugar derived) out of the US (just google brazil ethanol imports).

    • 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.

    • Excellent point, it's the first thing that crossed my mind when I read the article. At 6x the energy to produce it than you get back, government subsidies would have to be huge. As a matter of logic, divide all government subsidies by the number of gallons of ethanol produced. Examine the subsidy-per-gallon (SPG) in comparison to the cost-of-gas (COG). Unless SPG is more than 5x greater than COG, there's no way it takes 6x as much energy to produce a gallon of ethanol than it creates. Otherwise, the makers
  • Don't drive gas guzzlers. Don't drive unless you need to. Maybe while you're at it you might as well bike or walk some places and lose some weight reducing the burden on health care.
    • Talk to me when you do this in Phoenix Arizona in the middle of summer.

      When the nightly LOWS don't go below 90.
      When the daily HIGHS don't go below 110 or 115.

      Then bike or walk even the mile or two to the grocery store, and see how you feel. I'll visit you in the hospital where you'll be taken when you keel over from heatstroke. Oh wait, you'll be placing a burden on health care. Whoops.
      • Surely the middle of the summer isn't year round and that still doesn't mean you need a gas guzzler.
      • Talk to me when you do this in Phoenix Arizona in the middle of summer.

        When the nightly LOWS don't go below 90.
        When the daily HIGHS don't go below 110 or 115.

        Then bike or walk even the mile or two to the grocery store, and see how you feel. I'll visit you in the hospital where you'll be taken when you keel over from heatstroke. Oh wait, you'll be placing a burden on health care. Whoops.


        As someone who has spent a lot of time living in the desert and doing various field work there, I feel fairly confiden
      • Hey, if someone's stupid enough to live in the fucking _desert_, that's just too damned bad, isn't it?
      • a) if it doesn't go below 110 or 115, it's a low

        b) WTF are you doing living in a place you're so poorly adapted to?

  • There was a reason, back in the day, that gasoline was chosen to power vehicles. That is, its energy-density is very high. In fact, in terms of fuels that are stable enough to be in a vehicle, I am sure that gasoline is very very close to the top. That is why it became (and remains) the dominant fuel for automobiles. Alternative fuels (hydrogen fuel cells, ethanol) are simply to inefficient and expensive. Though gas is such a nasty pollutant, is the economically (think micro and short-term) smartest ch
    • Gasoline may be a good choice, but I claim the reason it was chosen was that it was an abundant waste product of other industrial processes. Steam cars were otherwise very attractive. Here I speculate: Rockefeller bought some politicians to bring gasoline online.
  • corn is used to produce ethanol, ethanol is burned and gives off carbon dioxide, and corn uses the carbon dioxide as it grows

    Ixnay. Politicians know ethanol is crap. It just gives them a better story when pushing for farm subsidies. For more information, see Homeland Defense Funding [answers.com]
  • In a nutshell (Score:4, Interesting)

    by Linux_ho ( 205887 ) on Monday June 27, 2005 @04:37PM (#12925374) Homepage
    The author is using data from thirty-year-old production techniques to shoot down the new "buzz" about tomorrow's efficient ethanol production. At the same time, he is ignoring the current research that is generating the buzz: researchers are just now coming up with efficient ways to produce enzymes that can turn raw agricultural waste into ethanol. That means stuff like sawdust, wood pulp, cardboard, corn stems, yard waste etc can be turned into ethanol instead of going into landfills.

    Data about how much energy it takes to grow corn is irrelevant, because we won't be using corn. We'll be using lawn clippings, or pulverized construction waste, or re-re-recycled paper, or whatever.
    • Re:In a nutshell (Score:3, Insightful)

      by Linux_ho ( 205887 )
      Oh, I almost forgot. Using sugar-based production techniques developed over the past 20 years, Brazil currently manufactures huge quantities of ethanol and sells it on the international market for approximately $30-$35 per barrel. Most of the ethanol the US imports comes from Brazil. If producing it was so inefficient, I'd expect it to be a lot more expensive, wouldn't you? Compared with current oil prices (>$50/barrel?), and the potential for efficiently producing ethanol from agricultural waste in the
  • the energy required to produce gasoline?
  • Six times the energy input does not necessarily work out, especially if the input energy is low level process heat, sunlight, or other "cheap" sources of energy.

    "Taking grain apart, fermenting it, distilling it and extruding it uses a lot of fossil energy," he said. "We are grasping at the solution that is by far the least efficient."

    Consider the process of making ethanol from corn. You plant some field corn and let it grow. There is some energy involved here but mostly human labor and sunlight is inv

    • For processing, since this corn is not for consumption I would imagine you could let it dry on the cobs, soak it down to sprout it, and then toss it into some kind of grinder to pulverise it into a very coarse mash. By sprouting it you allow the natural process to create mashing enzymes and sugar similar to barley malt.

      Nope. Corn doesn't contain amylase or other starch-splitting enzymes, and none are produced by sprouting it, either. In brewing, corn must be mashed with a diastatic malt like barley or yo

  • In other news, researchers have discovered that it takes six top stories being posted to Slashdot to get one piece of real news.
  • by brandido ( 612020 ) on Monday June 27, 2005 @05:12PM (#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.
  • Six times more energy than end product delivers, not six times more energy than gasoline; there's a big difference.

    If you look at the site a previous poster mentioned ( here [state.mn.us] ), you'll see that ethanol's energy yield is 1.34, while gasoline's is 0.805. Obviously, that is nowhere near a 6x difference.

    Also, the thing about portable fuel sources vs how much energy it takes to make them gets people thinking the wrong way. I'll put it in terms nerds can understand. It's like a desktop machine vs a laptop. A des
  • It didn't take long to find two things:

    (1) Making this case seems to be all Patzek ever does

    (2) He may not be wholly unbiased.

    Here's the Google search [google.com] and here's one of many interesting results... [ilcorn.org]
  • Here in the U.S. we live in a capitalist society, but the ethanol industry enjoys a large government subsidy. How large is it and how much does the ethanol actually cost? The U.S. Federal government subsidizes ethanol with a 54 cents per gallon (gallon of ethanol, that's 5.4 cents per gallon of 10% ethanol fuel then) tax credit, and states also give credits individually.

    1) Let's factor out those credits. Say someone wants to make 90/10 gas/ethanol to take advantage of the tax credit. How much will the

    • Some gas stations are starting to carry E85 at the pump (85% ethanol, 15% gasoline).

      The problem with burning straight ethanol is that it will eat the rubber bits in the fuel system (at least that used to be the problem - perhaps newer cars can handle it?).

      • Ethanol is not a problem if you car was made anytime since the late 1970s. Cars older than that had problems, but gas often contains 10% ethanol, and that is enough to cause problems. Therefore you can be sure any car on the road will have no problem with ethanol. At least as far as the rubber parts are concerned.

        The problem with pure ethanol is you need a different mixture, most fuel injection systems and carburetors are set up for gas, which burns leaner than ethanol. Run E85 in a normal car for l

    • Here in the U.S. we live in a capitalist society, but the ethanol industry enjoys a large government subsidy. How large is it and how much does the ethanol actually cost?

      It's difficult for us to use ethanol, mainly because we don't have the infrastructure to make, distribute, and burn it in our engines at more that 10% concentration. Yet. So that's the main problem. Switching over our cars, distribution infrastructure, and manufacturing facilities will be a huge cost. But we can look at Brazil to get some
    • 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 i

  • First, try thinking about it in the terms Bucky Fuller suggested: energy is the real value, and money is just an abstraction of it. They are interchangeable because they're inseperable.

    Of course it's ineffecient. If it were efficient, it'd be cheap, and nobody could make money doing it, and so wouldn't do it on a scale useful to a population which is incapable of doing it for themselves.

    Unaddressed is the complete cost of its use in terms of cleaning up the biosphere mess after. It's unaddressed because i
  • by iwadasn ( 742362 ) on Monday June 27, 2005 @10:03PM (#12928210)
    Do keep in mind though that not all energy is created equal. If it takes some number of units of heat and electricity, we needn't assume they come from oil. Really, studies like this need to break things out into "portable" and "non-portable" energy forms. If it uses more portable energy than it produces, then it's a loser. If it uses less portable energy, but some additional amount of non-portable energy then it could still work out OK.

    At the end of the day, we don't make electricity out of oil, so a process that uses electricity and produces oil/ethanol might be useful if we need oil, and have electricity to burn.

    This is one of the primary justifications for things like widespread solar and nuclear power sources. Though they don't help our dependence on oil directly, by giving us a limitless/very large source of electricity, we are more able to undertake processes that consume electricity but produce oil/ethanol, helping to reduce the constraints on oil supplies.

    Another good example of this is Hydrogen. Hydrogen production is important, but not because you'll run your car on it. It is used in all sorts of industry (including oil refining), and can easily be used with Thermal Depolymerization (TDP) to produce oil from all sorts of useless trash, literally. We currently make hydrogen from natural gas, so it's not worth it to use that hydrogen to make oil, but if we could make it from something else, then the whole equation changes. Lots of industry that burns natural gas or coal, or uses it chemically, could use the produced hydrogen instead, and the natural gas could be used to power vehicles, or even be directly converted into oil.

    It's very much interconnected. Saving electricity doesn't really help here, as we would still be converting coal to oil, which isn't really so helpful from an environmental standpoint. Dramatic new sources of power, however, like widespread solar or nuclear allows us to convert effectively limitless energy to an oil like form, and would change things dramatically.

    Once again, life is more complicated than what passes for journalism these days.
  • by gregor-e ( 136142 ) on Monday June 27, 2005 @10:50PM (#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.
  • IN THE ARTICLE, they state that this research is based on 35 year old production techniques! The submitter conveniently overlooked that bit of information though, because, if it's not hydrogen and fuel cells it must not be good enough. TFA goes on to say that based on the latest information released from the USDA, Ethanol produces 67% more energy than is needed to create it. I pass this along, only so the common /.er who doesn't have time (doesn't care) to read the article will be better informed.
  • I was doing some research for a "Green Diesel" company, O2 Diesel and examine their competitors: Diesel+water, Diesel+ethanol, FT Diesel (from coal), Natural Gas (converted to diesel), Vegetable Oil. Every single time I looked at the figures, vegetable oil seemed to make the most sense. It is totally renewable, there is capacity (just about) and it has lower emissions at source(not as good as pure ethanol, but better than fossil oil) and, because your growing more foods, the total emmission cycle was signif

"I'm a mean green mother from outer space" -- Audrey II, The Little Shop of Horrors

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