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America's First Cellulosic Ethanol Plant

Posted by kdawson on from the sounds-corny-but-isn't dept.

hankmt writes "The state of Georgia just granted Range Fuels a permit to create the first cellulosic ethanol plant in America. Cellulosic ethanol produces ethanol from cellulose, which all plants have, instead of from sugar, which is only abundant in food crops. Corn ethanol only produces 1.3 units of energy for every unit of energy that goes into growing the crop and converting the sugar to ethanol. Cellulosic ethanol can produce as much as 16 units of energy for every one unit of energy put into the process. The new plant will be online in 2008 and aims to produce 100 million gallons of ethanol a year."

6 of 522 comments (clear)

  1. Where do these numbers keep coming from? by plover · · Score: 5, Interesting
    This isn't the first time I've read that corn yields 1.3 units of energy out for each unit put in (or some factor other than 1.3) But where does this number come from? And really, how far back does it go -- gas in the farmer's 4x4 inspecting his fields? Energy used to produce the fertilizer? The energy to produce the food the farmer ate?

    I'd like to know because it's so hard to compare with oil at that level. It's much easier for a consumer to simply look at the price on the pump. But that only tells us what the market is willing to bear (what the fuel is worth), not the true costs of production.

    --
    John
    1. Re:Where do these numbers keep coming from? by aichpvee · · Score: 5, Interesting

      It isn't about monetary value at all anyway. It's about corn being a poor source of material for producing ethanol because it is low in sugar. This type of ethanol works great in places like Brazil because they make it out of sugar cane.

      If it were just about the monetary cost of things even corn ethanol wins over oil, which would be $13/gallon or more if we started charging the oil companies for our military services.

      --
      The Farewell Tour II
    2. Re:Where do these numbers keep coming from? by Gibbs-Duhem · · Score: 5, Informative

      It comes from a selection of five papers from the late nineties which did the calculation in a number of ways. Generally, they attempt to account for the entire manufacturing process, from energy in oil used in fertilizers to fuel for farm equipment, to transport of the ethanol or corn, to the refineries that distill out all the water. I do not believe they go so far as to account for feeding the farmer, but I honestly suspect that is a very minor correction, as much as I like farmers.

      However, there is a fairly well known outlier which claimed to do a better job of accounting for processing costs. Pimentel and Patzek attributed what they claim are more accurate inputs to the agriculture, transport, industrial, and distribution components of the manufacturing process, giving the also oft-quoted value of around 25% energy *loss*. Ordinarily, people would probably dismiss that one given the seemingly overwhelming amount of contrary evidence, but Pimentel and Patzek are very well-respected scientists. It's difficult for me, as an energy researcher, to know who to believe. I suspect it's nigh impossible for people who only study this passingly.

      Personally, I'm inclined to believe that even if Pimentel et al are wrong, 1.3 is just way, way too low to be reasonable. Improvements to technology (as this plant represents), are the only way that ethanol can ever be practical. We'll see soon enough if it's as good as they claim.

      http://www.news.cornell.edu/stories/July05/ethanol .toocostly.ssl.html has a summary of the debate.

  2. Skeptical by Bombula · · Score: 5, Interesting

    You have to be careful of these kinds of companies' claims. I remember getting interested in a biodiesel-from-algae-grown-vertically project run by an outfit called Global Green Solutions (www.globalgreensolutions.com). They claimed to be able to get 150,000 gallons per acre per year, which is 1000 times the output of oil palm and other biodiesel crops - and 15 times more than other folks' projections for regular algae ponds. It all sounded great, until the basic calculations showed that their 'projections' would have meant converting 85% of the TOTAL solar energy directly into stored energy in the fuel - a physical impossibility. I called their bluff, and they just shrugged and said, "our 100-million-gallon-per-year plant will be open next year and then you'll see." Well, it's now next year, and you can imagine what happened. Nothing.

    --
    A-Bomb
  3. Re:Anything like this is a good thing by Vader82 · · Score: 5, Interesting

    I don't mean to be contrary, but spewing carbon into the air isn't a bad thing. Its introducing EXTRA carbon into the air that hasn't been there for millions of years thats a bad thing. If we stopped pumping oil out of the ground today and instead used biofuels of whatever variety you like (biodiesel, ethanol, etc) that would be enough. The carbon in the air would get sucked up by plants as they grow, we would harvest said plants for the energy they have locked up, and we would use it.

    The carbon-hydrogen class of molecules have excellent energy storage properties, from methanol (CH4) up to octane (C8H18). Some have higher energy density, cleaner burning, etc. Humanity has around 100 years of investment into the internal combustion engine and it would be wise not to do away with that until we've found something SIGNIFICANTLY better. And by significantly, I don't mean 20-30%. I'm thinking more like 100-300% before it really looks worthwhile.

    Anyhow, if we stopped introducing EXTRA carbon back into the surface carbon cycle thats been sitting locked away for the last 10M+ years that'll be enough to do one of two things: stop any potential increase in surface temperatures OR show us that there is a different cause than CO2 causing warming.

  4. Re:Still harder to make than corn by Suicyco · · Score: 5, Informative

    See here:

    http://fuelandfiber.com/Hemp4NRG/Hemp4NRGRV3.htm

    Hemp is one of the top producers of biomass per acre. It is much better than corn and can be grown on fallow fields as well. And you can't even smoke this type of hemp, it grows 10-20 feet high and is all stalk with a clump of seeds at the top. Of course, nobody ever smoked this form of hemp, even when it was one of the primary cash crops of the south prior to the 1930's.

    Too bad, since hemp is evil. It makes you rape white wimin: http://www.oddfrog.com/paper.htm