Science says: Ethanol good on energy, not so much on environment 6

The "Findings" column on WaPo has this cryptic tidbit:

Ethanol -- alcohol produced from corn or other plants -- is more energy-efficient than some experts had realized, and it is time to start developing it as an alternative to fossil fuels, researchers said yesterday.

Although some critics have said the push for ethanol is based on faulty science and mostly benefits the farm lobby, several reviews and commentaries published today in Science argue otherwise.

"We find that ethanol can, if it is made correctly, contribute significantly to both energy and environmental goals. However, the current way of producing ethanol with corn probably only meets energy goals," said Alexander Farrell of the University of California at Berkeley. [my emphasis]

That sent me to Science, but of course I can't read it without a subscription. It does have this short description of the week's contents:

With fossil-fuel supplies steadily waning, recent research has focused on using plant-derived materials as a renewable substitute (see the Editorial by Koonin). Ragauskas et al. (p. 484) review progress in this area, ranging from plant genetics research for enhancing supply to enzymatic and other catalytic methods for breaking down the biomass into practical fuels and fine chemical precursors. Some of the economic challenges and benefits of changing the production infrastructure on such a large scale are also addressed. Ethanol is a renewable resource already in use as a liquid fuel, but its production from corn and cellulose is energy intensive, and some analyses have found that the overall process uses more energy than it creates. Farrell et al. (p. 506) rigorously analyzed a variety of relevant investigations, and found that the studies reporting negative net energy values are flawed. All of the studies show that current corn ethanol technologies reduce petroleum use significantly relative to gasoline. However, new production methods are needed if fuel ethanol is to reduce greenhouse gas emissions significantly.

Anybody get Science? Want to send me a copy?

David Roberts is staff writer for Grist. You can follow his Twitter feed at twitter.com/drgrist.

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  1. James Hrynyshyn's avatar

    James Hrynyshyn Posted 9:25 pm
    26 Jan 2006

    Science Magazine article on BiofuelsAnyone who would like a copy of the PDF that David is talking about, just email me: jamesh (at) cyamid.net

    James Hrynyshyn

    website: http://www.cyamid.net

    blog: islandofdoubt.net
  2. meander Posted 1:33 am
    27 Jan 2006

    Link and public spreadsheetThe blog Green Car Congress has an extended and slightly more technical summary of the article (link).  The article's authors have made available the spreadsheet that they used to compare the methodologies (link).  
  3. Biodiversivist's avatar

    Biodiversivist Posted 3:50 am
    27 Jan 2006

    Synopsis of biofuel articles in today's ScienceAn editorial:
    The chief scientist for BP wrote the Science editorial, which should help to dispel the "big oil wants to suppress biofuels" conspiracy theory. He concludes by saying, "In the jargon of the petroleum industry, the "size of the prize" is too large to ignore." If they run the biofuels industry as environmentally responsibly as they have the fossil fuel industry, we are in big trouble.
    There is not a single mention of biodiversity loss resulting from deforestation.
    Credible studies show that with plausible technology developments, biofuels could supply some 30% of global demand in an environmentally responsible manner without affecting food production. To realize that goal, advanced biofuels must be developed from dedicated energy crops, separately and distinctly from food.
    Keep in mind, he is talking about global demand for liquid fuels which account for about 30% of all energy needs, meaning the studies are talking about 9% of total energy needs.
    Reading between the lines, he is saying that biofuels as produced today are a dead end. I tend to agree. He is talking about "advanced biofuels." Futuristic plans to create ethanol from plant cellulose using enzymes, as opposed to how it is done today, making it like all moonshiners do, by distilling corn or sugarcane mash in a still. Of course, he is no better at predicting the future than anyone else. If these technologies finally come into existence (note that to date, they have produced next to no fuel at all) they still have to be grown on land somewhere, and the only land available happens to be rainforests in Africa, Asia, and South America, and the conservation reserve land carbons sinks here in the US.
    He envisions another green revolution using genetic engineering:
    There are major technological challenges in realizing these goals. Genetic improvement of energy crops such as switchgrass, poplar, and jatropha has barely begun
    A paper about giant futuristic biofuel refineries:
    The paper is one long-winded discussion of ideas that exist only as research subjects. It is like reading a science fiction story filled with way too much science jargon:
    In essence, the modern biorefinery parallels the petroleum refinery...future reductions in the ecological footprint of energy generation will reside in a multifaceted approach that includes nuclear, solar, hydrogen, wind, and fossil fuels (from which carbon is sequestered) and biofuels.
    No mention of the other way to sequester carbon, by allowing forests to grow for hundreds of years. Replacing forests with biofuel crops tends to neutralize the positive effects.
    The authors were also enamoured with words that start with bio:
    The current production and use of bioethanol and biodiesel processes are a starting point. It is our belief that the next generational change in the use of bioresources will come from a total integration of innovative plant resources, synthesis of biomaterials, and generation of biofuels and biopower
    A little reality sneaked in:
    For chemicals derived from biomass, this dominance will be transferred to solvent-based extraction...Regardless of which process technologies are incorporated into a biorefinery, almost all will generate some waste products that will be intractable and difficult to convert to value-added biomaterials or biofuels. These spent-biomass residues will contain fragments from lignin, residual carbohydrates, and other organic matter. This residue will need to be treated in an environmentally compatible manner, with the smallest ecological footprint
    They finish by enthusiastically telling us how important it is that we find new sources of energy, as if that were not obvious. The question is, what will the new sources look like?
    Nonetheless, given humanity's dependence on diminishing nonrenewable energy resources, this is a challenge that must be addressed--and we need to get on with it!
    A paper on ethanol:
    There is nothing new here. They make the same argument that corn ethanol is energy positive if you give credit for feeding the waste products to cows. If you don't, then it is a push.
    The studies that "correctly" [my quotes]accounted for this displacement effect reported that ethanol and coproducts manufactured from corn yielded a positive net energy
    I stated once before, the weak link is that lots of cows are already fed waste products from all kinds of farm products. You can only claim an energy credit by displacing animal feed made from corn. So, their claim is only partially correct, and depends entirely on whether a given farmer uses say, peanut hulls, or corn to feed his cows. The fact that the paper does not address that critique means that they have overlooked it. Nobody is perfect.
    An important point is that they validate research that shows the process releases greenhouse gas emissions similar to those of gasoline. And that large-scale use of ethanol for fuel will almost certainly require cellulosic technology.
    Government interference in free market forces is acknowledged:
    Greater quantities of ethanol are expected to be used as a motor fuel in the future because of two federal policies: a $0.51 tax credit per gallon of ethanol used as motor fuel and a new mandate for up to 7.5 billion gallons of "renewable fuel" to be used in gasoline by 2012
    At least they made a passing mention of the potential for biofuels to destroy the planet:
    Additional environmental metrics are now being developed for biofuels, and a few have been applied to ethanol production, but several key issues remain unquantified, such as soil erosion and the conversion of forest to agriculture...Looking to the future, the environmental implications of ethanol production are likely to grow more important



    In the end, it all comes down to biodiversity. Help acquire and protect ecological hotspots, give to a conservation organization: http://www.saveourbiodiversity.com
  4. Tom Philpott's avatar

    Tom Philpott Posted 4:23 am
    27 Jan 2006

    Way to go, biodiversivistGW Bush's staunch support of ethanol is another example of how the oil industry isn't trembling in fear over ethanol.
  5. amazingdrx Posted 5:16 am
    27 Jan 2006

    AllianceAn alliance between those who oppose nuclear power and those who oppose agri-chem-bizz biofuel might be a wise move.
    The pro-nuclear and pro-agri-bizz biofuel enviros  have driven a wedge into the environmental movement thus weakening it.
    Gaia forbid that mega-corp biofuelers and nukers figure out that  waste nuke heat to process biofuel-cogeneration will drop the cost of ethanol sifnifigantly, altering the economic equation.
    An environmentalist alliance based on a shift to electric vehicles powered by renewables might already be too late to beat the publicity wave behind biofuel and nukes.
    It's a hopeless cause, the very best kind of cause!



    http://amazngdrx.blogharbor.com/blog
  6. solarkismet Posted 12:34 am
    30 Jan 2006

    Links to StudiesScience Link:

    http://www.sciencemag.org/cgi/content/short/311/5760/506
    The report, model, and supporting materials:

    http://rael.berkeley.edu/EBAMM/
    From the paper on the negative ethanol studies:
    "Two of the studies stand out from the others

    because they report negative net energy values

    and imply relatively high GHG emissions and

    petroleum inputs (11, 12). The close evaluation

    required to replicate the net energy results showed that these two studies also stand apart from the others by incorrectly assuming that ethanol coproducts (materials inevitably generated when ethanol is made, such as dried distiller grains with solubles, corn gluten feed, and corn oil) should not be credited with any of the input energy and by including some input data that are old and unrepresentative of current processes, or so poorly documented that their quality cannot be evaluated (tables S2 and S3)."



    www.organic-blue.com

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