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Power Science

America's First Cellulosic Ethanol Plant 522

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."
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America's First Cellulosic Ethanol Plant

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  • by plover ( 150551 ) * on Sunday July 15, 2007 @06:13PM (#19870933) Homepage Journal
    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.

    • by aichpvee ( 631243 ) on Sunday July 15, 2007 @06:17PM (#19870969) Journal
      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.
      • Re: (Score:2, Informative)

        by ScrewMaster ( 602015 )
        It's even worse than that, since methanol production is heavily subsidized by the Federal Government.
        • by mdsolar ( 1045926 ) on Sunday July 15, 2007 @07:47PM (#19871577) Homepage Journal
          These guys are going for ethanol though they also get some methanol, propanol and butanol. Look at step 2b here: []
          Solar power with no maintenance fee: -selling-solar.html []
      • Re: (Score:3, Interesting)

        by ChrisMaple ( 607946 )
        At some point you have to say "It's not valid to count this as a cost." Why not charge military expenses to the existence of religious insanity? Why not add the cost of building roads to the price of oil? How about the cost of educating future oil company employees, or feeding them until they join the oil company?
        • Re: (Score:2, Insightful)

          by tepples ( 727027 )

          Why not add the cost of building roads to the price of oil?
          This already happens in the form of tax on the sale of gasoline.
      • Re: (Score:3, Interesting)

        You make a hell of a point. I say we fund the war through gas taxes. You want to end this war tomorrow add a $10 tax on gas to cover the cost of fighting for it. Even Congress might be on the people's side when it costs them $600 to top off their Hummer.
      • Sugar (Score:5, Insightful)

        by Mark_MF-WN ( 678030 ) on Monday July 16, 2007 @01:55AM (#19873591)
        Thanks for not reading the article... or even the headline. The article is about CELLULOSIC ethanol. You know, cellulose? The stuff that isn't sugar?

        You can make cellosic ethanol from grass clippings, those bags of leaves that everyone is getting rid of each falls, fallen tree branches, corn husks, not to mention the tonnes of produce that each and every grocery store throws away every single day because it couldn't be sold.

    • by evanbd ( 210358 ) on Sunday July 15, 2007 @06:26PM (#19871045)

      Comparing prices also gets subsidies (especially corn subsidies, but also renewable energy subsidies) involved.

      Those numbers certainly ought to include the energy content of the fertilizer -- it's decidedly non-trivial in comparison to the output energy, though I don't have a reference handy so I won't go quoting numbers. Most fertilizer is ammonium nitrate (or other nitrates), which is made from atmospheric N2 + H2 from fossil fuel sources (mostly natural gas, but also oil and coal to some extent). The ammonia is oxidized to nitric acid and reacted with more ammonia to form fertilizer AN, or used directly as anhydrous ammonia.

      • Corn?! (Score:3, Funny)

        by Mark_MF-WN ( 678030 )
        Where is all of this gibberish about corn coming from?! The article is about cellulosic ethanol -- it's right there in the title. No corn is required. You can make cellulosic ethanol from grass clippings, from tree branches, from discarded copies of Atlas Shrugged, etc. I'm pretty sure those things don't require fertilizer... except maybe the grass, and even then it's only to satisfy the needs of people with so little to entertain them that their sole joy in life comes from getting grass to grow as fast
    • Re: (Score:2, Informative)

      by Anonymous Coward
      The DoE publications and others are all fairly consistent at a factor of 1.2 to 1.4. High sugar sources, like sugar cane, are over 3:1 ratio. High oil-content plant products like soybeans are also over 3:1. That is the "direct" energy cost. Includes the energy for the tractor but not energy for the farmer. The tractor fuel really is negligible... the real cost is in the heating of the water and lost water needed to make ETOH from corn. Sort of like using an electric raxor uses less energy than a plai
    • by mdsolar ( 1045926 ) on Sunday July 15, 2007 @07:30PM (#19871465) Homepage Journal
      This is the ratio of fossil energy put in to energy out. Most of the fossil energy input for corn comes from nitrogen fertilizer which is produced using natural gas (though it does not need to be .html []) and fuel used for harvesting and planting. Some distilleries also use natural gas. Forest waste products to be used here don't have any fertilizer inputs and much of the fuel used for harvesting would have been used anyway. Brazil is achieving some very impressive values for this ratio in its biodiesel production: []. On the energy out side, everything is really stored solar power.
      Get solar power with no installation cost: -selling-solar.html []
    • by slughead ( 592713 ) on Sunday July 15, 2007 @07:48PM (#19871579) Homepage Journal
      But that only tells us what the market is willing to bear (what the fuel is worth), not the true costs of production.

      Actually, it's especially easy with gas. The 'demand curve' is so steep, usually quantity demanded remains very constant regardless of price (at least, in the short term, obviously).

      This is noted by gas taxes: the burden is almost entirely bore by the consumer, so an extra 18 cent tax adds nearly 18 cents to the price of gas because the companies know we'll pay it. In addition from gas taxes end up being nearly proportional to the rate.

      Compare this with something like cigarettes taxes: The companies actually reduce the price of cigarettes and end up paying (I'm guessing here, from my days as a smoker) roughly half of the tax. This is directly related to the demand curve and the nature of the market. In addition, revenues are not nearly proportional to the tax rate increase because people generally do buy many fewer cigarettes when they cost more. The companies have to balance the tax burden with their loss of revenues, and they hire really smart guys to do this.

      By the way, the emboldened words in this post are there to indicate trends and averages.
    • by Gibbs-Duhem ( 1058152 ) on Sunday July 15, 2007 @07:52PM (#19871601)

      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. .toocostly.ssl.html [] has a summary of the debate.

      • Care to explain why someone might have tagged this story "badnews?"

        How could this be bad news in any context?
        • by Ajehals ( 947354 )
          Presumably its potentially bad news if you are an oil producing country and want to still be selling oil to the states in 50 years time (at whatever ridiculous rate). Its also potentially bad news if you currently produce ethanol from corn and want to continue to supply it in the future.

          Although I agree with you its good news from, an economic, geopolitical and environmental point of view at least.
      • Re: (Score:3, Informative)

        by dman123 ( 115218 )
        Pimentel and Patzek are well respected? Maybe in the petro and bug worlds, but in the biofuel world? Hardly. They are well known for self-referential justification of their "facts" and citing old data (again, usually their own papers from long ago). All you have to do is read this paper a nol/08_22_01b.htm [] by Michael Graboski: Research Professor, Department of Chemical Engineering, Colorado School of Mines. And that's a kind review of Pimentel/Patzek. It's #1
    • Re: (Score:3, Insightful)

      by mothlos ( 832302 )
      What they fail to figure is the opportunity cost of turning all of that cellulose into ethanol vs. its current use, which is largely animal feed and compost that is used to make products, as cover for off seasons, and to enrich soils for another season of crops. What is the energy cost of destroying your soil or offsetting the loss in other areas of the economy?

      The number comes from estimates that agricultural analysts make about the energy inputs of farm production. Human inputs are generally not considere
    • by Jerf ( 17166 ) on Sunday July 15, 2007 @09:13PM (#19872177) Journal
      There's one and only one way to find out if ethanol-from-corn is a net win, or in fact any other alternative energy proposal: Strip it of all subsidies and throw it out into the marketplace. (More advanced students will note that we also need to internalize the appropriate externalities.)

      If it is in fact an energy-positive process, the extra energy can be sold. If the process is economically viable, then pretty much by definition of "economically viable" they will be able to run at a profit. If it is not, then they will eventually go out of business.

      Now, my point is not that this is desirable. It must be the ultimate goal of any alternative energy production system, but in the short-term you can make good arguments about subsidizing things to get over start-up costs, experiment with multiple things before we know which is the correct answer, etc. My point is simply that you can do math from now until the last drop of oil is pumped out of the ground and you won't really know whether such a marginal process is truly net-positive.

      That's the beauty of money; it's hard to wrap your mind around it, but if you just let it do its thing, it will automatically account for labor costs, equipment costs, etc., and with some judicious law making (which has a roughly 0% chance of happening) it can account for the externalities as well, and the final result will be obvious and unambiguous. It can even account for corruption and mismanagement etc., which are really real risks, not illusions. It's the only way to go from theory to reality.
  • by lecithin ( 745575 ) on Sunday July 15, 2007 @06:15PM (#19870943)
    But hey, it is something.

    How would hemp do?
    • Re: (Score:2, Funny)

      by Spookticus ( 985296 )
      if you used hemp, you would then have all these people getting upset over people smoking it instead of using it for fuel.
    • by meburke ( 736645 )
      Kudzu! We could do a lot for the environment by making paper, cloth and now ethanol from kudzu.
    • by Suicyco ( 88284 ) on Sunday July 15, 2007 @07:56PM (#19871637) Homepage
      See here: []

      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: []
    • Re: (Score:3, Informative)

      by daeg ( 828071 )
      Hemp, while good, isn't the best. It'd work in most climates, at least, and is certainly better than a lot of choices for yield per acre.

      Switchgrass is one of the better ones. It grows everywhere and is very disease, drought, etc resistant. You can't kill the shit even if you try and it requires very little, if any, maintenance. For longer term crops, depending on the environment type, poppler and willow are good choices. The nice thing about fast-growing trees is that if your refining process gets tied up,
    • How would hemp do? (Score:5, Informative)

      by falconwolf ( 725481 ) <falconsoaring_20 ... minus cat> on Sunday July 15, 2007 @10:30PM (#19872583)

      In 1892 Rudolph Diesel designed his engine and ran it on vegetable oil. He used hemp oil amoung them. Then in the 1930s Henry Ford built a vehicle not only using hemp [] in the construction but was fueled with alcohol made from hemp, hemp he grew on his Iron Mountain Estate. Hemp was found to be a good source for fuel. Also in the 1930s MIT did a study showing an acre of hemp produced more paper than an acre of forest. Eventually some who felt threatened by hemp's industrial uses pushed to make it illegal and via the 1937 Marijuna Tax Act [] and between them they were successful.

  • Cellulosic? (Score:5, Funny)

    by Icarus1919 ( 802533 ) on Sunday July 15, 2007 @06:23PM (#19871013)
    What the hell kind of adjective is that? It's bullshity.
  • by Anonymous Coward
    People were just decrying the permits issued to BP for a plant to crack Canadian oil.

    The ethanol plant uses a two-stage process to turn cellulose into gas, and then crack the gas into ethanol. Bet the emissions might be interesting.

    Do we hold these guys to the standards we expect out of the oil companies, or do they get a pass because they are "greener."

  • by gregor-e ( 136142 ) on Sunday July 15, 2007 @06:25PM (#19871041) Homepage
    DOE has ponied up $385 million [] to six different cellulosic ethanol plants, one of which is Range Fuels.
  • Skeptical (Score:5, Interesting)

    by Bombula ( 670389 ) on Sunday July 15, 2007 @06:26PM (#19871049)
    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 ( 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.
    • Re: (Score:3, Interesting)

      by Smidge204 ( 605297 )
      I think your math was off...

      1 gallon of BioDiesel is about 130,000 BTUs or energy. 150,000 gallons is thus 19,500,000,000 BTUs.

      Realistically, sunlight energy at ground level is about 100 watts per square foot, plus or minus. At 43,560 sq.ft. per acre, that's 4,356,000 watts per acre of raw sunlight.

      Assuming a cautious 5 hours a day, every day, of sunlight at that wattage, a year will net you 4356000 watts * 365 days * 5 hours/day * 3600 sec/hour = 28,618,920,000,000 total incident joules of sunlight.

      • Re:Skeptical (Score:5, Informative)

        by Bombula ( 670389 ) on Sunday July 15, 2007 @09:27PM (#19872249)
        Here's another calculation:

        The energy contained in 150,000 gallons of diesel @85% = 150,000 gallons/year x 133,000 BTU/gallon x .000293 kwh/BTU = 5.8MMkwh/year acre. The energy falling on one acre of land = 5kwh/m2 - day x 365 days/year x 4046 m2/acre = 7.4MM kwh/year - acre. 5.8/7.4 = .78. That is about 78% efficiency in converting sunlight to liquid energy.

        I incorrectly remembered the 85% figure, which is a different measure, but it's still in the same neighborhood.

        Looking at your calculation, you seem to have forgotten to convert BTUs into joules. 1 BTU = 1,054 joules. That put your calculation out by a factor of 1000. You got 0.07%, when the actual number is closer to 70%.

        I wish you were right though.

  • Sure, it's not Mr. Fusion, but this technology sure as heck sounds cool.

    On the flipside, I wonder what sort of waste products this plant is going to produce...
  • This is a good step, but what is needed is work on thermal depolymerization technologies. These can turn waste, be it plastic bottles, dead goats, papers, or pretty much any organic item and turn it into usable crude oil.

    Long term, its still just a patch... what is really needed are batteries with far more energy density than what we have now, and more research into fission, fusion, solar, and other energy generating technologies that don't spew carbon into the air.
    • by jandrese ( 485 )
      The problem with thermal depolymerization is that it requires a tremendous amount of energy compared to what you get out of it.
      • How is it inefficient? The primary plant in Carthage, MO, is running at about the efficiency ratio predicted early on, where 85% of the energy content that goes in comes out as high-grade fuel oil. Looking at it from a different perspective, that's 15 parts energy use resulting in 85 parts energy in the oil, or a factor of ~5.7.

        There are some numbers that are off about the technology -- the amount of waste usable as input, for example -- but it seems to be an effective method of fuel production.
        • Re: (Score:3, Insightful)

          by Skreems ( 598317 )
          And that's only 85% if you consider industrial waste from a turkey processing plant to be "usable energy". If you consider the fact that they can run off of completely useless waste products, and feed 15% of their output back into the plant to power it, this is essentially free energy, AND a reduction in landfill contents.
          • Carbon is turned into carbon black and sold to ink manufacturers and such. The water is converted to steam (and that steam is actually recycled through the system to heat other parts of the process) and the water ruynoff from that is either reused in the process or discharged as clean water. The methane and butane gases are captured and either used in plant to power the plant, or sold. Metals and such are sold on the open market. Ditto with the calcium and other minerals. It's incredibly efficient and clean
        • by cdrguru ( 88047 )
          It's great as long as there is only one of these plants. After that, well...

          The problem is that when there is no market for turkey processing waste it is free or extremely low cost. When the second plant comes online there is now a bidding process that is going to happen (one way or another) for the raw materials - see, they aren't waste anymore. They are valuable raw materials now.

          Same thing happens with used vegetable oil. It is cheap and works fine as long as there is no market. Once there is a mark
    • by Vader82 ( 234990 ) on Sunday July 15, 2007 @06:46PM (#19871175) Homepage
      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.
    • These can turn waste, be it plastic bottles, dead goats, papers, or pretty much any organic item and turn it into usable crude oil.

      So it works on people too?

  • boil water and produce electricity? That should be a lot more efficient than turning it into moonshine.
    • Because they are specifically looking for a liquid fuel that can be used in internal combustion motors.

      I know, I know, you're thinking: electric cards, electric semitrucks, electric tractors, electric everything. Well it's not so easy.

      Liquid fuel appears to be a better energy sink than batteries at the moment by a long shot.

  • by N8F8 ( 4562 )
    Time to grab the chainsaw! Stop the bastard neighbor's tree from dropping leaves on my lawn AND fill up my car.
  • by q2k ( 67077 )
    Finally, a use of all that damn kudzu that is taking over GA
  • The only thermo-chemical method of producing alcohol from cellulose that I know of uses concentrated sulfuric acid. If this is what they're doing...

    And their explanation of expensive enzymatic reactions? Hogwash. Enzymes work for 1000's of turnovers (at a minimum) before they become poisoned and lose their efficiency. They don't go to ethanol solutions, they go to starch solutions, which then get converted to sugar (think beer), and THEN get converted to ethanol.

    That goes into a refluxing column, add a
  • by Anonymous Coward

    Compared to other North American crops, such as corn or switchgrass, HEMP contains the highest percentage of cellulose [].

    This is yet another reason to re-legalize industrial hemp in the US.

    This great annual crop, grows in even the most arid lands, virtually anywhere in North America, without the use of pesticides, or herbicides, and can be baled like hay for easy transportation. It can be used to make:

    • paper
    • rope
    • building material []
    • ethanol
    • methanol
    • bio-diesel
    • hemp-see
  • Nip / tuck (Score:5, Funny)

    by Zombie ( 8332 ) on Sunday July 15, 2007 @08:18PM (#19871825) Homepage
    Hmm? America making fuel from cellulite? What a good idea. There's certainly plenty of it.
  • by Soong ( 7225 ) on Sunday July 15, 2007 @08:36PM (#19871943) Homepage Journal
    just sayin, that'd be awesome.
  • by r_jensen11 ( 598210 ) on Sunday July 15, 2007 @08:39PM (#19871959)
    I know that the existing ethanol production systems have enormous tolls on our groundwater supply. How does using cellulose compare? Remember: there is more to the environment than just emissions. One of the last things we need is the Great Plains to become The Great Dunes
  • I'm worried (Score:3, Insightful)

    by bagsc ( 254194 ) on Sunday July 15, 2007 @08:43PM (#19871983) Journal
    If cellulosic ethanol works, say goodbye to things that are mainly made of cellulose, like rainforests. You think Indonesia gives a shit where the ethanol they sell you comes from? There's something much worse than global warming, and that's deforestation. If this technology works, its more dangerous than nuclear power to the ecology, and we need to be very careful who learns how to use it.
    • Re: (Score:3, Insightful)

      See your point, and I share in your general concern. However cellulosic ethanol, as produced using Range Fuel's proprietary technology, can be produced from just about any green biomass.. including corn stalks, cobs, switchgrass, sugar cane, agricultural waste, pig shit and wood chips/sawdust.

      What encourages me about this is we will be able to produce a very efficient, clean burning fuel domestically. As will just about any country that can grow wheat straw, corn or whatever else. Remember this is just

  • First? (Score:3, Interesting)

    by dbIII ( 701233 ) on Sunday July 15, 2007 @08:58PM (#19872075)
    Hang on - I'm way over in Australia and more than six months ago I heard a radio interview with people running an ethanol plant on cellulose in the USA (North Dakota or Montana - not sure which state). Australia's ABC science show ran the story but the podcast and transcripts have most likely gone by now.
  • by heroine ( 1220 ) on Sunday July 15, 2007 @09:09PM (#19872143) Homepage
    The fuel cell laptop was supposed to appear a few years ago. Still waiting for that one. Coal liquefaction was supposed to appear a few years ago. Still waiting for that one. Now a startup is promoting cellulose liquefaction.
  • by Ancient_Hacker ( 751168 ) on Sunday July 15, 2007 @09:23PM (#19872235)
    First the story's lead is total crap. The State of Georgia could print licenses for Interstellar Fusion Drives, for what it's worth. Which is nothing.

    So ignore the lead.

    Now for the meaty guts of the story..... cellulose to alcohol. Searching, searching, ...... Nope, not the teensy tiniest clue re : how they're doing it. Usually you'd see some words like "chemical process", "patent pending", or names and links to competent colleges, scientists, or chemical companies. Not a one.

    As to actual verifiable facts, here's only one, and it's non-sensical:: a 100 million gallon a year pilot plant.

    So lacking the tiniest foothold, and plenty of nonsense, we'll have to assume this is all PR crapola.

  • by RGRistroph ( 86936 ) <> on Sunday July 15, 2007 @09:33PM (#19872281) Homepage
    I have been doing some armchair research [] on gasification for a while. My original goal was to make a gas synthesizer that would be attached to a vehicle or small generator, as people did in some places during WWII. I have become less enthusiastic about that project, as I have come to realize it will be difficult to make any device that doesn't have the potential to kill you with carbon monoxide.

    If you are interested in the chemistry and thermodynamics behind gasification you should obtain and read "Synthetic Fuels" by Ronald F. Probstein and R. Edwin Hicks, published by Dover (1982, 1990, 2006), ISBN 0-486-44977-7. The first portion of it deals with gasification. The later parts of it deal with taking the "synthesis gas" and forming it into bigger molecules of methane or even liquid fuels. The amount of energy consumed, and the heats and presures and sometimes expensive catalysts, are fairly depressing to the backyard hobbiest.

    However, it might be possible to build something that gasifies waste into hydorgen and steam and carbon dioxide, which would then be burned in an engine. A recent slashdot article [] about a gasification procedure that uses microwaves [] seems hopeful, because if you gasified in the presense of steam with no oxygen you might have less carbon monoxide. Usually, oxygen has to be present because a portion of the waste is burnt in the same chamber as the gasification occurs, to provide the heat needed.

    Of course, playing around with a microwave magnetron has it's own dangers as well.

    I believe it is possible to build an apparatus about the size of two shipping pallets and 6 feet high that would take in household garbage and yard waste and produce a considerable amount of electricity. Whether it would be economical, except in places where grid electricity is not available, is a different matter. Having it produce a liquid fuel suitable for storage and use in an internal combustion engine seems like a big leap, but that's what I would like to aim for.

  • by J.R. Random ( 801334 ) on Sunday July 15, 2007 @10:05PM (#19872451)
    That is by far our most perpetually renewable resource.
  • by Animats ( 122034 ) on Sunday July 15, 2007 @11:50PM (#19872991) Homepage

    OK, first we get past the blogodreck from some site that wants traffic, and look at the Range Fuels site. []

    This is funded by Kosla Ventures, which is Vinod Kosla's venture capital fund. That's a good sign; he has a decent track record as a VC. (He was one of the founders of Sun, but he later invested in Excite.) Anyway, they're not looking for money; they've got that.

    People have been working on cellulostic ethanol for a while. It's not that hard to do; it's hard to do cost-effectively. Here's an overview of the known approaches. [] Range Fuels uses a heat-driven process, which of course takes energy to run, but is standard chemical engineering. There's other R&D underway to develop a bioengineered enzyme that will digest cellulose at commercially feasible rates. Such enzymes have been created, but they're too slow and making the enzymes costs too much. Work continues.

    Anyway, this doesn't look like the big cellulostic ethanol breakthrough. But it's progress.

  • One tonne of dry biomass on an energy basis is about the same as two barrels of oil. Another pithy fact is that one needs to be able to brew beer at $2.50 per keg in order to compete on an energy basis with gasoline. The last factoid is easy to see. A keg is about 60 liters and at 5% this is three (3) liters of ethanol. Ethanol has about 2/3 the energy of gasoline.

    We seldom see these issues described in a compact form. I keep seeing terms like "Ethanol is an oxygenated fuel". In fact it is a partially oxidized fuel which is why it carries considerably less energy than say gasoline or diesel. Liquid motor fuels are for the most part Alkanes and have a chemical formula of CnH(2n+2). Ethanol is an alcohol which has an OH tacked on to an alkane. Ethanol is C2H5OH which is a partially oxidized propane. The oxygen makes it liquid hence relatively safe and easy to transport. Methanol is partially oxidized methane: CH3OH.

    Hence it is immediately clear that if we had a large supply of propane then the shortest chemical route to produce ethanol would be from the gas - not from sugar or starch and certainly not from cellulose or other plant matter... except for one thing. The biologic source is renewable. The geological source as best we know is not renewable.

    Now the thing that is not emphasized in these discussions is that every gallon of ethanol produced from starch will come out of someone's mouth. It might not be your mouth or mine - it might be a pig's mouth or a chicken's mouth but it will be someone or something currently in the food chain who will have to give up their source of food in order for us to feed our cars.

    This is obvious. We do not have a HUGE amount of excess agricultural capacity and we also do not have huge piles of unused grain hanging around. Hence it is clear that we eat what we produce and there is little long term surplus.

    The world consumes about 82-84 million barrels of oil per day. This can be found in the BP statistical oil review - there are other sources but this is a very good one. North America consumes about 24-25 million barrels per day if you include Canada.

    I share the opinions of those who say we are probably at the world peak of oil production. We will probably stay near this peak for a couple years more. On the news two days ago was an EIA forecast that world consumption is forecast to grow by another 2 million barrels per day next year and that OPEC is expected to step up to the plate. I laughed. I expect that OPEC production will be flat and that the forecast demand will simply drive the price up until the demand is destroyed. Mathew Simmons says it could take over $300 per barrel to destroy the demand. I don't know if I believe what Simmons says will happen before 2015 but I do have a great deal of respect for him. He could very well be right.

    Now the issue of cellulostic ethanol. Probably this makes some sense. But you still need to collect and transport a tonne of organic matter to the ethanol plant in order to create the equivalent on an energy bassis of two (2) barrels of oil. Then this material has to be converted at 100% efficiency into ethanol and at zero (0%) cost.... and it has to be 100% convertable into ethanol.

    Other alternatives are coal liquifaction and coal gasification to create a hydrogen source for the development of synthetic crude.

    As I see it - the ONLY way that make sense is synthetic crude.

    We are doing this in Alberta at the tar sands. We are expecting to ramp up production into the 3.3 million barrel per day level by 2015. The problem is that by 2015 if world oil peaks between now and 2010 for instance then we can lose conventional production at a rate of 10% per year on a production base of say 84 million barrels at peak - and this compounds annually... it is an exponential function.

    Without nuclear power to create a source of hydrogen we either have to discard literally 1/2 of the carbon we mine or we have to use a chemical process such as Fis

To be a kind of moral Unix, he touched the hem of Nature's shift. -- Shelley