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Technology Science

Hydrogen Fuel Cells Running On Sunflower Oil 82

Posted by timothy from the flower-power dept.
tigersaw writes "You've heard about Biodiesel , Greasecars, and Fuel Cells for a while now. At yesterday's meeting of the American Chemical Society, researchers from the University of Leeds in England described a novel approach that combines these ideas in a fuel cell device that employs steam and two separate catalyts to generate hydrogen using sunflower oil. Experimental results show a hydrogen yield of 90 percent, versus 70 percent in other hydrogen fuel cell technologies. 'The sunflower oil used is the same type found on grocery shelves. "We would happily toss our salad with it," says the researcher, who adds that the process can also work with other types of vegetable oils.'"
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Hydrogen Fuel Cells Running On Sunflower Oil More

Hydrogen Fuel Cells Running On Sunflower Oil

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  • They toss their own salads?

  • Yikes... (Score:5, Funny)

    by keiferb ( 267153 ) on Wednesday August 25, 2004 @07:02PM (#10073970) Homepage
    "We would happily toss our salad with it,"

    They need a much, much better PR person.
  • best paid jobs of 2050:

    4. microsoft historian
    3. slashdot moderator
    2. crop flyer
    1. sunflower farmer
    • Sunflowers don't pay too bad right now. They're down some from what they have been in the past, but can still be very profitable.
      • I would have thought that canola or soybeans would be tough oilseed competition. Unless you were growing for florists (which has to pay bank).
        • Soybeans are a very profitalble oil seed. The only canola that is in the area was planted at the local Research-Extension Center. As for sunflowers for florists....no dice if they are oil seeds or confectionary. They go from one of the prettiest crops in the field to the ugliest in about a week.
          • I guess I should clarify, I would have thought that sunflowers would have to grow in fairly valuable farmland, while canola oil can be grown on the scrubbier parts of the north plains (where farmland is very cheap). I guess I was ignorant of the relative yield of sunflowers and growing costs. I'm sure the harvesting methods on sunflowers would reduce their astetic value significantly. Do they chop the heads or remove the seeds from them while standing? We grew all sorts of stuff in eastern washington, b
            • I'm from Northwest Kansas, so the farmland here is very good. Sunflowers lose their leaves, the stalks get very hard and brown, the heads lose their petals and turn brown. The texture of the dried stems/leaves and back of the heads is about like sandpaper. They are harvested with a row crop headed on a combine. The head is cut off and fed through the machine where the seeds are separated. Premiums are paid for low trash content and high oil content.

              Here are some links to pictures of fields that are re

  • Ultimate hippy car (Score:5, Funny)

    by jebiester ( 589234 ) on Wednesday August 25, 2004 @07:04PM (#10073987)
    A car that runs on flower power?. Wouldn't that make the ultimate hippy car?

    Especially as a VW combi van.

  • Tossing Salads (Score:2, Funny)

    by cdgod ( 132891 )
    I told myself, once tossing salads became a common part of slashdot, I would have to switch fields.

    That's it I now officially hand in my slashdot account.

  • Now where would all those sunflowers be grown, and what state will have to rename itself The Sunflower State?

  • This could actually be really cool... (Score:5, Insightful)

    by Drunken_Jackass ( 325938 ) on Wednesday August 25, 2004 @07:50PM (#10074338) Homepage
    The modern Hydrogen economy has to get over a huge hurdle in the wide-scale distribution network of H2.

    Distribution for H2 is pathetically inefficient. In order to ship it at an efficient level, they have to compress it into liquid form. That takes up a lot of energy, along with the associated costs of now transporting a very cold liquid (yeah - not very energy efficient either).

    If H2 can be made using a novel approach, you can minimize the huge potential transport and distribution costs by setting up a lot of small production facilities (local refineries?).

    This could be a pretty big deal.

    • Imagine... (Score:3, Insightful)

      by baywulf ( 214371 )
      Imagine if the $50 billion or whatever the US spent invading Iraq was spent of H2 research, production and infrastructure?
      • $50 Billion? Try $90 billion. Each year.

      • Re:Imagine... (Score:2, Interesting)

        by nelsonal ( 549144 )
        Do you have any concept of the amount of infastructure currently devoted to gasoline delivery that would largely be wasted in hydrogen distribution, or the amount of new infastructure required? And that is beside the point that they only way we can currently produce hydrogen on any sort of efficient scale is to strip it from crude or natural gas. I'd put a guess that the new h2 infastructure would cost two orders of magnitude byond your Iraq cost figure, and we would still be getting the h2 from oil (stri
      • Or imagine if the US had spent just $100 million on new votign machines that actually have printers. Then the Democrats might win.

    • Re:This could actually be really cool... (Score:4, Interesting)

      by mOoZik ( 698544 ) on Wednesday August 25, 2004 @10:52PM (#10075381) Homepage
      I disagree. On Alan Alda's "Scientific American Frontiers," they showed a novel approach in which hydrogen is produced "on site." That is, it uses a reverse fuel cell in every "hydrogen station" to develop hydrogen, then it is liquified, and delivered via hydrogen pumps, much like the way you pump gas, but with a slightly different hookup. That, in my opinion, is a better means of distribution as it completely eliminates the need for transport, pipes, large factories, and so forth.

      • But where does the energy to make the H2 come from? Currently, it takes a cubic assload of electricity to generate hydrogen, so the distributed production model would need huge increases in the electrical power generating infrastructure, which is already near maximum utilization.

        The alternate is producing the H2 at a location with cheap power (hydro, desert solar collectors), and then shipping the H2 where it needs to be. But that has its own issues, as you pointed out.

        I'll be honest - I'm not holding o
        • It's doesn't take "huge" power. In fact, it takes relatively little. The current infrastructure can very well handle the demands. Electricity costs cents. The production of hydrogen, its transportation, and given its unique state (pun unintended), shipping costs will be dramatically high.

          • The vehicular power requirements of the United States average close to 200 GW [blogspot.com]. Then you have losses in transmission, conversion and storage. Total US electric generation capacity in 2002 was about 900 GW. [doe.gov]
            • That is an agreement, correct? Sort of difficult to tell your implicit stance.

              • I'm interpreting it as agreement with me(of course).

                Your original post is correct in that the actual conversion is relatively efficient, i.e. 1W of electricity translates to 1 W (equivalent) H2, minus small losses. However, the energy requirements of autos & trucks are relatively high. So you would be adding to the electrical load on the grid by a lot.

                H2 is an energy transport mechanism, NOT a generation source. The initial energy must come from somewhere. Currently it comes out of the ground in t
              • If you are arguing that the power requirements of vehicles powered by electrolytic hydrogen are minimal, you are very much mistaken. The transmission grid has plenty of unused capacity during off-peak hours to move the required wattage, but the energy to fill that capacity has to come from somewhere. We're running our nuke plants flat-out most of the time, hydropower is limited, wind is a paltry few GW, natural gas supplies are tight; this means burning more coal in those few plants which aren't base-loaded
          • It takes a lot more energy to crack water than you would get from using it in a fuelcell otherwise... Well lets just say "Young man we follow obey the laws of thermaldymics in this house!"

            What I wonder is how does a sunflower powered fuel cell compair to the same sunflower oil being burned in gas turbine of even in deisel?
        • How long can you power the library of congress on a "cubic assload of electricity"?

    • Only if you ignore the realities (Score:5, Interesting)

      by Tau Zero ( 75868 ) on Wednesday August 25, 2004 @11:39PM (#10075586) Journal
      H2 from sunflower oil. Okay, sounds great. But tell me, how much sunflower oil would it take to power the nation (or any reasonable fraction thereof, such as the transport sector) using this invention?

      You don't know? Didn't even stop to ask?

      I didn't think so.

      Being a wet blanket bugs me sometimes, but somebody has to do the dirty work of dragging everything back down to earth and facing facts. Here are some:

      1. The reactor doesn't generate hydrogen with 90% efficiency, it generates hydrogen of 90% purity. Given that the off-gas is about half methane (RTFA) it appears to me to be very inefficient. (Note: neither the author nor your Slashdot editor bothered to RTFA either.)
      2. There are already engines, and even fuel cells, which can burn hydrocarbons directly. Sunflower oil makes reasonable diesel fuel as-is. Solid-oxide or molten-carbonate fuel cells can reform fuels internally, and while they might coke up on straight sunflower oil they'd probably work just fine after it had been steam-reformed a bit.
      3. Hydrogen as a motor fuel suffers from huge problems with storage. People see it as sexy but for all the wrong reasons.
      I could see this as another technology for making compact laptop power supplies whose fuel couldn't be used to bring down an airplane (just TRY making a fuel-air bomb with sunflower oil). The key to renewable energy? Gimme a break.
      • Agreed. I see anything touting of a hydrogen economy
        by politicians as dodging the immediate issues.
        It always seems that the promises will bear fruit AFTER the next election. Funny how that always seems to be the case. Until H2 storage problems are solved, all of this is a pipe dream. Make the switch to biodiesel blends, add ethanol to every tank of gasoline and insist on low-sulphur fuels NOW, not tomorrow, not next week,not 3 years from now and the atmosphere will take care of itself.

      • Re:Only if you ignore the realities (Score:5, Informative)

        by JGski ( 537049 ) on Thursday August 26, 2004 @12:54AM (#10075813) Journal
        Yep. Hydrogen is a pretty poor energy carrier (not energy source!!) for several reasons, first being energy "return": oil is 100:1 for Saudi oil (100 barrels out for 1 barrel in to cover extraction, transportation and refining) to as low as 10:1 for Alaskan/Texan oil. Compare to other sources: natural gas 50:1, wind 3:1, solar 4:1 (silicon fab operations and materials), ethanol 1:1 or less (need to count inputs from fertilizer and farmer equipment fuel), hydrogen 0.5:1 (energy in for electrolysis with losses plus transportation).

        And then since hydrogens's only a carrier (like a rechargeable battery - there is no such thing as a "hydrogen well") you still need a real energy source to "charge" it. Sunflower oil might be a potential source...until you do a back-of-the-envelope on how many arable acres you would have to grow it on and what percentage (most) of the US's arable acres are only so due to energy-intensive and oil-intensive farming providing water, fertilizer, pesticides, etc. and how much of the "naturally arable" land has been paved over for suburbs and cities (e.g. the entire Santa Clara valley aka Silicon Valley).

        Even this sunflower one makes me wonder: what are the fertilizer and farm equipment inputs? where does the energy for the steam come from? So what's the net energy return? I'd put money on it being no better than ethanol!

        An interesting post I saw else where: for good energy return on low density sources like biomass you want to have minimal energy inputs from petro or other sources. As an energy cash crop you want to have something that grows pretty much like a weed. Guess what produces good quality oil and grows like a weed? :-) Well, "weed" of course, or actually hemp. Wouldn't it be funny if we need to rely on hemp for the "Peak Oil" time.

        • Wouldn't it be funny if we need to rely on hemp for the "Peak Oil" time.

          Only a matter of time. Could you imagine the affect on existing markets if hemp/weed/pot became legal? Oil, cotton, alcohol, tobacco and otherwise? It would be a bloodless revolution. Well, maybe.
        • > first being energy "return": 10:1 for Alaskan/Texan oil. [...] ethanol 1:1 [...]

          Really? Where do you get your numbers from?

          According to the Wikipedia entry [wikipedia.org]. Considering the whole life-cycle oil has a yield of 1:1.843 for diesel petrol, and bioethanol one of 1:2.34

          > until you do a back-of-the-envelope on how many arable acres you would have to grow it on

          With high-yield rapeseed, 3% of the arable area of the US would be needed to cover its need of oil for transportation.

          Some Algae have even a be

          • With high-yield rapeseed, 3% of the arable area of the US would be needed to cover its need of oil for transportation.

            Consumption of diesel fuel in the USA in 2002 was 2.455 million barrels/day, [blogspot.com] or 39.4 billion gallons per year. At the high yield figure of 145 gallons per acre and 100% conversion to biodiesel, that would require the production of 271 million acres, or 425 thousand square miles.

            Total area of the USA is 3,618,784 square miles, [atlapedia.com] so you're talking 12% of the total land area (including Alask

            • My fault. Actually, rereading the link, I don't know where I get the figure.

              According to the University of New Hampshire [unh.edu], listed in the Wikipedia entry:
              Need: 140.8 billion gallons
              Required surface with algae: 9.5E06 acres
              Estimated Costs: $308 billion to build the farms.

              Total arable land in the US: 1030E06 acres
              • Interesting. At 145,000 BTU/gallon, some different options for energy conversion show how conversion efficiency matters:

                High-yield rapeseed, 145 gallons/acre/year (1.52 KWH/m^2/year)
                Algae-derived oil, 50000 gallons/hectare/year (212 KWH/m^2/yr)
                Silicon PV cells at 15%, receiving 700 W/m^2 average, 6 hrs/day: 230 KWH/m^2/yr
                Future PV cells at 50%: 766 KWH/m^2/yr

                Algae is pretty impressive, but doesn't hold a candle even to present-day solar panels (and the energy from solar cells does not require conversio

                • The advantages of algae are that they reproduce themselves and oil is more easily stored. Looks like the combination could be a winner.

                  This is the issue - wheras electricity can be made by many routes (Nuclear being the cheapest and most practical), fuels for transportation are much harder. Of all the biofuel approaches I've seen, only algal biomass comes close to making a large scale contribution, since it actually considers things like land requirements (deserts, which don't get used for anything much

            • ... we already produce WAY too much food as it is, don't we? Aren't we still paying farmers NOT to grow crops?
          • The 10:1 number is for gasoline rather than diesel. The number came from Saudi Aramco - a reasonably trustworthy source :-)

            The ethanol number is corn/maize ethanol - other non-energy intensively farmed plants certainly could do better.

            Rapeseed sounds interesting. It's weedy too so it might not take too much energy-intervention.

            Hmm. Algae has the issue of either which natural water resources (lakes, estuaries, oceans) you use for it (and how to get to it for harvest/maintenance) or what type of man-

        • I like how you ended that. You're right. It's been said that if 6% of the US landmass were growing hemp, our foreign energy needs would be zero. 6% of the US landmass is quite a bit of territory, but the stuff will literally grow in any part of the country. Having localized energy production capability in each state (or even county?) would be nice.

          Hemp played a big role during WW2 when our hemp supplies from the Phillipines were cut off by the Japanese. Even though the Marijuana Tax Act of the late 1930's

      • Re:Only if you ignore the realities (Score:4, Insightful)

        by bhima ( 46039 ) <Bhima@Pandava.gmail@com> on Thursday August 26, 2004 @03:30AM (#10076191) Journal
        I don't think it matters what percentage of energy consumption a given energy strategy will meet; because the hegemony of petroleum is not likely to be repeated soon, by any alternative energy sources.

        The real problem is the efficiency and the practicality. (Your other points)

        Biodiesel and Ethanol are good examples. Biodiesel can be made from a variety of sources, is efficient enough to be workable now, is compatible with the existing energy infrastructure, and is compatible with a large number of diesel engines (In fact I use B20 nearly exclusively). Ethanol is problematic in a number of ways, but still more or less workable. So given the right situations alternative energy sources can be useful, despite the fact that an entire economy doesn't use them. And given enough alternatives western societies can lessen their dependence on energy sources which must be purchased from unsavory regimes. This can be nothing but a good thing

        Unfortunately the site is down so I haven't read the article so I can't comment about this specific implementation. However, I view anything H2 related as problematic because of both its incompatibility with existing energy delivery infrastructure and the ridiculous hype surrounding it.

      • First, from TFA:

        "Producing hydrogen from sunflower oil could provide a more environmentally-friendly alternative by reducing [pollutants such as carbon monoxide and greenhouse gases like carbon dioxide and methane] while offering an abundant, low-cost and renewable resource that reduces dependence on foreign oil," says the study's lead researcher Valerie Dupont, Ph.D., an energy engineer with the University of Leeds in England.

        Of course, carbon dioxide and methane are also produced by the process, so I'm

  • Toss away. Just don't do it anywhere near me.

  • So.... (Score:3, Interesting)

    by Smidge204 ( 605297 ) on Wednesday August 25, 2004 @09:18PM (#10074868) Journal
    So how much energy is required to generate the steam that produces the hydrogen? Do you get enough H2 to make it worth the cost and effort?

    It's like an all-electric car... sure it uses no gas but that power has to come from somewhere to begin with. You've only moved the problem to someone else's back yard.

    At least with Biodiesel you get out more energy than you put in to make the conversion (the balance of the energy comes from the sun, which the plants have collected and turned into the raw oil).
    =Smidge=

    • Centralised Power (Score:5, Insightful)

      by sbszine ( 633428 ) on Wednesday August 25, 2004 @09:30PM (#10074940) Journal
      It's like an all-electric car... sure it uses no gas but that power has to come from somewhere to begin with. You've only moved the problem to someone else's back yard.

      That's the whole point: one problem to solve (at the power plant) instead of many to solve (at the cars). If you run many electric cars from a single power station, then you have:
      • one point to filter for emissions (in the case of fossil fuels)
      • no car pollution in cities(!)
      • an easy upgrade path when you replace your coal plant with biodiesel or solar or fusion or whatever
      • possible economies of scale (subject to electrical transmission losses)
      ...and so on.

      • Re:Centralised Power (Score:4, Interesting)

        by Smidge204 ( 605297 ) on Thursday August 26, 2004 @06:41AM (#10076643) Journal

        one point to filter for emissions
        That's not necessarily a good thing. Basically you would be concentrting all of the resulting pollution in one area instead of spreading it out more or less evenly. Assuming nature cleans up the pollution at a certain rate (say, as by density of plant life and large bodies of water to absorb and recycle CO2) then you actually made the problem much worse in some areas.

        no car pollution in cities
        Ah, well, as long as it's not in your back yard I guess it's okay then!

        an easy upgrade path when you replace your coal plant with biodiesel or solar or fusion or whatever
        Except that the existing power distribution system is already strained and aging such that it can barely keep up with peek demands today. It would cost billions upon billions to construct new powerplants and additional infastructure to handle the additional demand of the now millions of electrical vehicles feeding off of it.

        possible economies of scale
        See above. In general you try not to build powerplants too far from where the power is used (obvious?). And you will definately need more of them right from the start.

        Now take a straight biodiesel economy model:

        Virtually no infastructure costs. Everything you need to produce, transport and distribute liquid fuel is already in place.

        Less pollution on the grand scale. BD burns cleaner than the oil and coal (especially coal) used in powerplants, and the resulting pollution is spread out evenly such that nature can process it more effectively. If you're worried about soot (which BD produces less of anyway) there are already very effective filtering systems for small vehicles in widespread use.

        Excellent scaling economics. Unlike electricity you CAN produce/refine all of the BD in one spot for the entire country (even though you probably wouldn't want to). There is basically no restriction on the location of the refineries, and the distribution infastructure of trucks, boats and pipes is more flexible than high voltage transmission lines.
        The only problem is "where does te energy come from in the first place?", which the centalized electric system doesn't address either. Fusion power has to actually exist before you can even consider it, and all of the other possibilities such as oil, coal and nuclear all rely on the very same sources we're trying to get away from.

        I have read articles about the possible use of algae for BD production. According to the article (which I found a version of [unh.edu] on google) you can farm a high-oil content algae species for the purpose, which eliminates basically all of the problems of cultivating and fertilizing land for growing plants (algae doesn't need tilling...) Simply excavate a shallow lake somewhere relatively low and let gravity fill it with seawater, then start growing. If you're clever you can use a system of dykes to let the tide purge the lake for you and filter off the algae as the lake drains. Then you run it through a giant juicer and add a little methanol and lye to remove the glycerin from the product, and you got Biodiesel ready to burn in just about any existing vehicle.
        =Smidge=

        • Re:Centralised Power (Score:3, Interesting)

          by llefler ( 184847 )
          While I agree with your assessment of biodiesel being a good alternative to fossil fuels, I think you've missed some points on centralized production.

          Yes, all of your pollutants would be centralized as well. But a modern oil burning power plant will release dramatically less pollutants than the equivalent (ICE) internal combustion engines. With a power plant, weight doesn't matter. That allows them to focus on production efficiencies and reducing pollutants. As new technologies are invented they only have

          • Re:Centralised Power (Score:3, Interesting)

            by Smidge204 ( 605297 )
            For most people, if they didn't insist on driving huge SUVs, current electric technology would be more than sufficient.

            There are frequent brownouts in many urban areas during the summer because people are running their air conditioners. It's less frequent where I am, but it still happens. If the existing system can't fully satisfy peak demands, then switching everyone to electric cars is only going to make the problem worse - even "off-peak" charging, since off-peak will then become peak as millions of pe

        • Re:Centralised Power (Score:3, Insightful)

          by Pentagram ( 40862 )
          one point to filter for emissions

          That's not necessarily a good thing. Basically you would be concentrting all of the resulting pollution in one area instead of spreading it out more or less evenly. Assuming nature cleans up the pollution at a certain rate (say, as by density of plant life and large bodies of water to absorb and recycle CO2) then you actually made the problem much worse in some areas.

          I think that the poster's point was the potential to use technology to reduce pollution, such as stack scr

        • Except that the existing power distribution system is already strained and aging such that it can barely keep up with peek demands today. It would cost billions upon billions to construct new powerplants and additional infastructure to handle the additional demand of the now millions of electrical vehicles feeding off of it.

          A strange argument. Because your power grid is in havoc you don't see a chance for electric cars?

          So, you don't plan to fix your power grid?
          You don't plan to reduce energy consumptio
          • A strange argument. Because your power grid is in havoc you don't see a chance for electric cars? So, you don't plan to fix your power grid? You don't plan to reduce energy consumption, which could lift some pressure from the grid?

            No, the entire power distribution system does need to be upgraded and expanded. But the question is by how much?

            If all-electric cars become popular in the market, electrical demand would not just increase, it would explode. Unless you've prepared for the surge in extra demand t

    • At least with Biodiesel you get out more energy than you put in to make the conversion (the balance of the energy comes from the sun, which the plants have collected and turned into the raw oil).

      Even that isn't a given. I wouldn't be surprised if the energy needed to plant sunflowers, reap them, move them, extract oil from them, get rid of the waste, etc is already more than the energy present in the oil. I wouldn't be surprised if it was the other way around either (I just don't know), but people often

      • It's not a given, but surprise, surprise, the research has been done, and the energy input is about the same as required extracting and refining petrodiesel.

      • I wouldn't be surprised if the energy needed to plant sunflowers, reap them, move them, extract oil from them, get rid of the waste, etc is already more than the energy present in the oil. I wouldn't be surprised if it was the other way around either (I just don't know), but people often forget these costs.

        Then be surprised: its the other way around :D

        In germany there is a big research project regarding that topic and we currently supply our diesel needs to 0.5% from bio diesel.

        angel'o'sphere

    • It's like an all-electric car... sure it uses no gas but that power has to come from somewhere to begin with. You've only moved the problem to someone else's back yard.

      This is a general missconception repeatred all the time on /. when the talk about differnt ways of handling energy comes up.

      Suppose you drive your car wih gasoline, then about 15% of the energy combusted is hitting the road in terms of acceleration.

      This does not even take into account refining and distributing gasoline. A common number

  • Byproducts (Score:2, Insightful)

    by Anonymous Coward
    In the article they mentioned that the byproducts of methane and carbon dioxide were produced. Isn't it possible to generate electricity using methane? I remeber hearing about some dairy farmers that were doing that. I don't know what the effects of that would be, but it could be one more way for the system to become even more efficent, and possibly self sustaining.

  • hydrogen cars? Helium Blimps! (Score:1, Interesting)

    by Anonymous Coward
    Why don't americans stop living in the suburbs and move back into the cities where they could perhaps bicycle or *gasp* walk to locations instead of insane hour long commutes. Perhaps all that hydrogen could inspire a blimp comeback - who needs anti-grav when we already have balloons? Sure they're flammable, but with helium that's not an issue. I'd like to see an antagonist element try to take out a building by crashing an airbourne bouncy-castle into it...

  • Why hydrogen? (Score:3, Interesting)

    by david.given ( 6740 ) <dg@cowlark.com> on Thursday August 26, 2004 @05:54AM (#10076520) Homepage Journal
    The thing I don't understand is why everyone's focusing on hydrogen as an energy transport medium. It's lousy. Sure, the energy-per-unit-mass is high, but to store it you have to use high-pressure containment vessels or cryogenics. Complex and expensive. Just pumping the stuff from one tank to another is problematic.

    Why not use a fuel that's liquid at STP? Ethanol, say? The energy-per-unit-mass is lower, but it's so much denser you end up with a far higher energy-per-unit-volume. Storing and pumping liquids is a solved problem; you can use the existing infrastructure built by the petrochemical industry. Ethanol can be burnt and synthesised by fuel cells, too.

    So what's with the hydrogen obsession?

    • Re:Why hydrogen? (Score:1, Informative)

      by Anonymous Coward
      Because hydrogen only produces water vapour as it burns and not CO2 (plus H2O), like ethanol etc. Plus hydrogen storage has come on a long way, with foam and aluminium cell type storage mediums being used.

    • Re:Why hydrogen? (Score:1, Informative)

      by Anonymous Coward
      The problem with Ethanol as a fuel for fuel cells (solid oxide FCs) is that you will have coke (carbon) formation at the anode, which will kill the catalyst sites, and thereby the cell will stop producing electricity. Moreover, coke formation will probably cause the cells to rupture, as the stresses caused by the carbon deposits are fairly large. A lot of research is currently being done on finding new anodes that inhibit coke formation, like using copper instead of nickel as a catalyst.

      The second problem

      • Re:Why hydrogen? (Score:3, Interesting)

        by david.given ( 6740 )
        I thought the coke problem had been solved --- methanol fuel cells for small electronics are just beginning to go into production. How do these avoid it? Do they just assume that the lifetime of the fuel cell is going to be short enough that they don't need to worry about it?

        And besides, there's other ways of using the stuff. Steam reformation will break methanol down producing hydrogen, which you can then feed into the fuel cell. If all else fails, just burn the ethanol in an IC engine.

        And as for produ

        • Sure, you can use steam reforming to produce hydrogen. The problem with steam reforming, however, is that it requires a lot of energy (you need a lot of heat and pressure - 1000K and 4bar). So the whole point is to avoid reforming.

          The methanol fuel cells being produced by Toshiba use a polymer electrolyte at low temperature. The low temperature only forms CO2 without the formation of coke.

          SOFCs on the other hand, are generally high temperature (1200K), that will form coke if fed hydrocarbon fuels directly

  • Cute but bunk ... (Score:3, Insightful)

    by fygment ( 444210 ) on Thursday August 26, 2004 @11:06AM (#10079153)
    ... because:

    1) by-products are carbon dioxide and methane.

    2) unseen by-products: whatever is required to grow sunflowers (fertilizers & their production, tractor fuel by-products, etc)

    3) scaling: how many sunflowers does it take to make how much usable fuel?

    4) scaling: how much viable farm land can afford to be lost to the production of "fuel" vice "food"?

    Fuel cells are really neat. The problem of fuelling fuel cells is huge. Even without fuel cells the whole concept of biomass based fuels simply can't scale to current demand [doe.gov] . Think about it, the U.S. produces amounts of oil measured in millions of barrels per day to sustain current consumption (let alone what it imports)! What quantity of biomass is required to come close to that and what are you willing to sacrifice to do it?

    Sorry, but this story is a non-starter. If we're serious about addressing the dangers of fossil fuels, then we have to cut back on our energy consumption first and foremost. Anything else is just a "diet pill" approach. Don't change your fuel or engine, learn to live without/depend less on the vehicle(s).

  • Amazing... (Score:2, Informative)

    by zxflash ( 773348 )
    I find that many people are quite pessimistic when it comes to the feasibility of alternative fuels. Encouraging research such as this is good for the general public's morale, hopefully sooner than later American farmers, rather than terrorist states will power our vehicles.

    BBC also has a story on this... [bbc.co.uk]
    • American farmers? Not likely. If this kind of thing ever becomes reality, somebody else with fewer regulations will certainly grow the crops cheaper.
  • ... really. Here's [newscientist.com] a link stating that cigarettes are greater polluters than diesels. It makes it hard to really focus on what the greater ill is. Are our vehicles really greater polluters than our industries (seems unlikely in the Third world)? Are fossil fuels truly the great satan or might they actually be the most efficient source of energy we currently have despite their imperfections? Or perhaps there are more dangerous and ubiquitous polluters closer to home as this article suggests.

  • A better catalyst? (Score:4, Informative)

    by Randym ( 25779 ) on Thursday August 26, 2004 @03:23PM (#10082046)
    The catalysts, which are key to the process, orchestrate a series of chemical maneuvers that ultimately result in an increased hydrogen yield. First, one of the catalysts (the nickel-based unit) absorbs the oxygen from the air and this interaction heats up the reactor bed of the device. Simultaneously, in the presence of heat, another catalyst (a carbon-based adsorbent) releases any carbon dioxide previously trapped in the device.

    I wonder if they have tried this one [scienceblog.com]. It's designed to supress methane production and increase hydrogen production.

    From the article:
    ...a Raneynickel catalyst, named after Murray Raney, who first patented the alloy in 1927.

    Raney-nickel is a porous catalyst made of about 90 percent nickel (Ni) and 10 percent aluminum (Al). While Raney-nickel proved somewhat effective at separating hydrogen from biomass-derived molecules, the researchers improved the material's effectiveness by adding more tin (Sn), which stops the production of methane and instead generates more hydrogen. Relative to other catalysts, the Raney-NiSn can perform for long time periods (at least 48 hours) and at lower temperatures (roughly 225 degrees Celsius).

  • Can it run on "I cant believe this is not butter"..
  • http://www.hyweb.de/index-e.html/ [hyweb.de]

    That link covers efficiency and basic major players in europe. Its the portal site to the companies doing EU funded research in hydrogen power and also to prducts currently available.

    angel'o'sphere

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