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Biotech Science

Is Ethanol the Answer to the Energy Dilemma? 342

Posted by samzenpus
from the I-love-the-smell-of-alternative-fuel-in-the-morning dept.
n0xin writes "According to Fortune, "The next five years could see ethanol go from a mere sliver of the fuel pie to a major energy solution in a world where the cost of relying on a finite supply of oil is way too high." In an effort to meet fuel-economy standards, automakers already have 5 million ethanol-ready vehicles on the road. Supporters are optomistic that "we can introduce enough ethanol in the U.S. to replace the majority of our petroleum use in cars and light trucks." Are SUVs included in this category?"
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Is Ethanol the Answer to the Energy Dilemma?

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  • SUVs (Score:2, Informative)

    by Nerd-o-mancer (665180) on Wednesday January 25, 2006 @09:48PM (#14564065)
    Yes, the government tallies SUVs under that "light trucks" category, because they are (or used to be) built on truck frames. The only difference was they had cabs that went all the way back.
  • No (Score:3, Informative)

    by PorkCharSui (583216) on Wednesday January 25, 2006 @09:50PM (#14564081)
    Ethanol would take up too much of our ag land that we need to sustain our food supply. Check the movie The End of Suburbia (http://endofsuburbia.com/ [endofsuburbia.com] for a preview of our sad future.
  • Very interesting (Score:4, Informative)

    by mendaliv (898932) on Wednesday January 25, 2006 @09:50PM (#14564083)
    It looks like there's finally a use for all the grass clippings coming out of suburban neighborhoods and non-office paper that gets thrown away instead of being recycled.

    From the article:
    Instead of coming exclusively from corn or sugar cane as it has up to now, thanks to biotech breakthroughs, the fuel can be made out of everything from prairie switchgrass and wood chips to corn husks and other agricultural waste.

    This biomass-derived fuel is known as cellulosic ethanol.
  • Wrong. It could. (Score:5, Informative)

    by burne (686114) on Wednesday January 25, 2006 @09:53PM (#14564101)
    Ethanol made from plants will form a closed carbon-cycle. Ethanol sythesized from non-fossil sources will form a closed carbo-cycle.
  • Re:Still doesn't (Score:4, Informative)

    by Fatchap (752787) on Wednesday January 25, 2006 @09:54PM (#14564105)
    It also reduces the amount of Sulfur release, reducing acid rain. As acid rain has contributed to the deforestation of Scandinavia quite considerably, a reduction in atmospheric Sulfur may allow these to grow back and over time photosynthesis some of the CO2 back to Oxygen.
  • by bennyp (809286) on Wednesday January 25, 2006 @09:59PM (#14564139) Homepage
    Ethanol fuel is made of corn. Corn is grown using industrial processes which rely heavily on oil-based fertilizers and oil-fueled machinery. A much better solution is hemp-oil.
  • by acidblood (247709) <decio@dec[ ]net ['pp.' in gap]> on Wednesday January 25, 2006 @10:12PM (#14564227) Homepage
    What we really need for Ethanol to take off is a proper hybrid vehicle capable of burning both gasoline, ethanol, and various blends.

    These are all over the place here in Brazil. Last I heard, something like 80% or 90% of small cars were sold with hybrid ethanol-gasoline engines (nicknamed Flex around here). Many shops (even small ones) already have the technology to convert an ordinary gasoline engine to a hybrid, and it isn't that expensive either.

    I should remark that Brazil was a pioneer in the usage of ethanol for car fuels, but in the last decade or so it was getting out of fashion. With the advent of hybrid engines we're seeing a revival of sorts, particularly given the lower price (which unfortunately has been rising though).

    For my part, I believe the future is biodiesel, not ethanol, though.
  • Re:No it's not (Score:5, Informative)

    by TripMaster Monkey (862126) * on Wednesday January 25, 2006 @10:13PM (#14564234)

    Ethanol need not be produced from corn...From TFA:
    Instead of coming exclusively from corn or sugar cane as it has up to now, thanks to biotech breakthroughs, the fuel can be made out of everything from prairie switchgrass and wood chips to corn husks and other agricultural waste. This biomass-derived fuel is known as cellulosic ethanol.


    Cellulosic ethanol requires little far machinery and no pesticides. From Renewable Energy Access [renewablee...access.com]:
    We can't remember how many times we've been asked the question: "But doesn't ethanol require more energy to produce than it contains?" The simple answer is no-most scientific studies, especially those in recent years reflecting modern techniques, do not support this concern. These studies have shown that ethanol has a higher energy content than the fossil energy used in its production. Some studies that contend that ethanol is a net energy loser include (incorrectly) the energy of the sun used to grow a feedstock in ethanol's energy balance, which misses the fundamental point that the sun's energy is free. Furthermore, because crops like switchgrass are perennials, they are not replanted and cultivated every year, avoiding farm-equipment energy. Indeed, if polycultured to imitate the prairies where they grow naturally, they should require no fertilizer, irrigation, or pesticides either. So, according to the U.S. Department of Energy, for every one unit of energy available at the fuel pump, 1.23 units of fossil energy are used to produce gasoline, 0.74 of fossil energy are used to produce corn-based ethanol, and only 0.2 units of fossil energy are used to produce cellulosic ethanol.
    Between its lesser environmemtal impact (up to 80% reduced emmisions) and its cost-efficiency, cellulosic ethanol is far more environment-friendly than fosil fuels.
  • by brunes69 (86786) <slashdot AT keirstead DOT org> on Wednesday January 25, 2006 @10:41PM (#14564421) Homepage
    Regardless of what crop is used to produce it, ethanol requires areable land, and lots of it.

    To produce enough ethanol to sustain the US alone, would require hudreds of thousands of acres of crops. Regardless of the sustainability of the crops, it is a huge management issue in and of itself to control all that production.

    Hydrogen, on the other hand, can be produced readily in a power-plant type fashion.

  • by dido (9125) <dido@imperi[ ]ph ['um.' in gap]> on Wednesday January 25, 2006 @10:52PM (#14564500)

    A look at a small table [eroei.com] of energy return on energy invested figures gives ethanol from corn a 1.3, ethanol from sugarcane something like 0.8 to 1.7 (meaning it could possibly be a net energy loser!), and ethanol from corn residues 0.7 to 1.8. Compare that with petroleum's EROEI, which is today something of the order of 23, and had once been higher than 100. Even at the maximum efficiency level, it would probably take dedicating all of the arable land in the United States to grow corn for conversion to ethanol to allow business as usual. Also, mechanized farming techniques are so heavily dependent on petroleum-based (and natural gas based) fertilizers and pesticides. Here's a good article [fromthewilderness.com] on how to properly evaluate these schemes for alternative energy, and ethanol doesn't fare very well.

    No, the only real solution to the energy crisis is to abandon the grossly wasteful American way of life, and take steps towards serious conservation efforts.

  • Like this Ford? (Score:2, Informative)

    by sonofagunn (659927) on Wednesday January 25, 2006 @11:10PM (#14564599)
  • To produce enough ethanol to sustain the US alone, would require hudreds of thousands of acres of crops.

    Want a ballpark figure? 640 000 acres = 1 000 square miles [google.com]. That's smaller than the State of Rhode Island (1 545 sq.mi) [google.com]

  • Re:Like this Ford? (Score:3, Informative)

    by AKAImBatman (238306) <<akaimbatman> <at> <gmail.com>> on Thursday January 26, 2006 @12:48AM (#14565111) Homepage Journal
    It runs up to 85% Ethanol. Which sucks. And blending the fuel types on your own can result in unexpected timing problems. Using a Stirling, OTOH, allows you to burn any mixture of fuel without concern for timing issues. In fact, such an engine could burn just about any fuel, including hydrogen.
  • Re:No (Score:3, Informative)

    by realilskater (76030) on Thursday January 26, 2006 @01:24AM (#14565249)
    Actually, producing ethanol does not take up our agricultural land. Ethanol that is currently produced in the corn belt is produced from the waste of farming operations. The ears of corn are harvested and sold to the usual buyers. The stalks that are normally made into feed for livestock are first sent to an ethanol plant where the sugars are extracted and made into alcohol through fermentation. After the sugars are extracted the stalks are made into feed for livestock as they would have before. The production of ethanol in the US has been steadily increasing in recent years and will continue that way for the forseable future. It is also worthy to note that ethanol is mixed with 5% gasoline before it leaves any production facilities. The denatureing of the ethanol is to prevent if from being taxed and treated under laws as the alcohol it is.

    Other sources of fermentable materials is currently being reasearched. Some of the sources that have been researched range from various types of trees such as birch and spruce to food processing wastes like chicken and fish entrails. The bottom line is that ethanol is a viable source of alternative energy.
  • Re:Still doesn't (Score:5, Informative)

    by Belseth (835595) on Thursday January 26, 2006 @01:30AM (#14565274)
    I agree on all counts but I would add that there are other sources for ethanol than corn and some grow on arid land. One issue that's rarely discussed is that a lot of land is growing government subsidized crops that are essentially unneeded. If the land was used instead for ethanol or oil crops there would be a net gain. So long as the farmers get their subsidies they don't care what they grow. The problem usually comes down to a lack of communication between government departments. Much of the government opperates like warring camps competing for financial resources. If there was more cooperation in the government many of these problems would go away. Alternative sources are taboo because the oil companies are threatened by them. If it was simply a matter of wanting to stay on the oil standard we'd be romancing Canada for oil sand oil but the government has been ignoring the largest known source of oil. Why? Domestic oil companies have no control of that source. By invading Iraq we gained control of one of the largest current sources. It helps keep the domestic oil companies in control of the money. I hate to see the oil sands become the answer because that means a drastic increase in global warming. I hate the term global warming because it's deceptive. It's climate destabilization in truth. Notice the record cold and snow falls in Hawaii that no one in memory can remember seeing? It's part of the same effect and the global warming models predicted it. Everyone shouldn't be afraid of global warming it's the backlash which is global cooling that should make people afraid. Remember during the last round half of the US and virtually all of Canada was under an ice sheet. Europe is scared. Why aren't we? Just how many record hurricanes do we need in a year before some one wakes up and smells the CO2?
  • by The Fink (300855) <slashdot@diffidence.org> on Thursday January 26, 2006 @03:29AM (#14565613) Homepage

    Of course, oil isn't energy positive either.
    Okay, sure it's energy positive from the time we extract it from the ground, but any fair consideration needs to take into account the amount of energy that, once upon a time, was required to create that oil, since essentially what we're required to do is replace the whole supply chain (or, wait a few hundred thousand years -- or more! -- for the supply chain to replenish the stocks we've taken).

    I'm led to believe that the figure is approximately 24 tonnes of plants to produce one litre of petrol as an end product [eurekalert.org]. Considered this way, then ethanol, biodiesel or hydrogen are all far less energy negative.

    The bonus is that waiting several hundred thousand years for the fuel supply to renew itself isn't necessary with the other energy-negative part-solutions.

    Oh, and converting a standard four-stroke petrol engine to run on ethanol is not that hard, either -- as proven by a recent entry of a 1925 Austin in the Darwin to Adelaide [ninemsn.com.au] Panasonic World Solar Challenge. Bigger carburetor jets (or similar adjustments in a fuel injected vehicle), cylinder head lubricant (probably not necessary on most unleaded vehicles), and some timing adjustments are about the mix of it, and come to think of it EFI systems could be designed to handle such adjustments mostly automatically.

  • by ajs318 (655362) <sd_resp2NO@SPAMearthshod.co.uk> on Thursday January 26, 2006 @08:03AM (#14566161)
    Cellulosic ethanol is ethanol derived from cellulose.

    The idea is simple. You take any plant matter containing cellulose {a long chain polysaccharide which is fairly immune to yeast}, and hydrolyse the cellulose into mono-, di- and short-chain polysaccharides. Then you have something that will undergo fermentation.

    Any dilute acid will hydrolyse cellulose, but then you have the problem to get rid of the acid {which will harm the yeast} without creating a salt which also will harm the yeast. {Might it be possible to use a base whose salt with the chosen acid is insoluble in water, and filter out the precipitate? Since solubility is affected by temperature, it should be possible to refrigerate the mixture in the neutralisation tank to help it precipitate, and dump the waste heat into the hydrolysis tank to speed up the reaction. Further Work Required.} Alternatively, there may exist enzymes which will decompose cellulose into sugars and starches. If these are found to be compatible with yeast it may be possible to work a single-stage conversion, otherwise it will be necessary to do a multi-stage process, neutralising the first enzyme before fermentation ..... this does not seem to offer any advantage over the use of a dilute acid.
  • Re:No (Score:4, Informative)

    by AndersOSU (873247) on Thursday January 26, 2006 @09:39AM (#14566563)
    That's not what I've read. EtOH isn't produced from waste because of pitfully low yeilds, kernal is used because it has a high card (fermantable) content. The waste is waste because its mostly fiber, not good for eats or anything else.

    The stalks aren't made in to feed, the seed is, again for the same reason - low carb content. And I really hope you mean the cob and not the stalk, because if you've ever driven by a corn field you can clearly see that they don't even bother to pull up the stalk.

    The production of EtOH has been increasing, but the appropriate question to ask is would it be cheeper than gas if the EtOH subsidies were removed. It wouldn't have two years ago, but we may be getting close to the point where it is now.

    However, if a farmer is going to sell a portion of his crop to EtOH production, that is all it would be used for.

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