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Power Science

Scientists Use Microbes to Produce Hydrogen 190

Posted by Zonk from the free-as-in-beer dept.
An anonymous reader writes " Environmental engineers at Penn State University and a research scientist at Ion Power Inc. have created an electrically-assisted microbial fuel cell that can be used to produce hydrogen from organic material. The amount of electricity needed for the process is less than the amount required to power a standard cell phone. This advancement can be used to produce hydrogen as a byproduct of water treatment. " Coverage at ScienceDaily as well.
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Scientists Use Microbes to Produce Hydrogen More

Scientists Use Microbes to Produce Hydrogen

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  • Methane (Score:5, Funny)

    by LiquidCoooled ( 634315 ) on Sunday April 24, 2005 @04:28PM (#12331750) Homepage Journal
    I have been using microbes to produce methane for a while now, why can't I run my computer from that?

    Need extra power for that long haul flight, just eat a curry before hand!

    • Re:Methane (Score:1, Funny)

      by Anonymous Coward
      I have been using microbes to produce methane for a while now, why can't I run my computer from that?

      Try directing the methane towards a Zippo lighter

    • Re:Methane (Score:5, Funny)

      by Rosco P. Coltrane ( 209368 ) on Sunday April 24, 2005 @04:34PM (#12331793)
      I have been using microbes to produce methane for a while now, why can't I run my computer from that?

      I suspect the H2S you produce along with the methane might upset your computer.

      Need extra power for that long haul flight, just eat a curry before hand!

      Hmm, I'd like to see the face of the passenger seated next to you when you plug your fuel cell to the "source of energy"...

    • Re:Methane (Score:2, Funny)

      by debilo ( 612116 )
      I have been using microbes to produce methane for a while now, why can't I run my computer from that?

      I am not sure you'd like to try that, look what happened to goatse!

    • Bring some cows into the fold...never underestimate the power of bullshit.
    • Your own hand should be the last thing you eat.

    • Re:Methane from curry (Score:4, Funny)

      by lheal ( 86013 ) <`moc.oohay' `ta' `9991laehl'> on Sunday April 24, 2005 @05:13PM (#12332052) Journal
      Your digestive system requires (and produces) various enzymes to digest different foods. Without the proper enzymatic mix, digestion is inefficient and a gaseous output results.

      To get a decent methane volume, you have to vary your diet in a pathological way. Eat a sudden excess of foods you seldom eat. Try a progresson of beans - kidney beans, great whites, navy beans, blackeyed peas, and of course, the dreaded garbanzo. Mix in some onion varieties periodically. Then there are the peppers: bell peppers, jalapenos, and even habaneros are very efficient in terms of obtaining the desired output.

      Stay away from rice and noodles, as these seem to lessen the effect.

      I understand that certain vegetables - broccoli, cauliflower, asparagus, for example, can also have dramatic benefits if consumption is managed properly as above.

      Unripe apples and certain kinds of nuts are good candidates, but I find them to quickly lose their efficacy, and so they should be either reserved for a special occasion (such as a wedding or funeral) or simply enjoyed for their non-flatulent properties.
    • Of course I didn't RTFA, but if them lil microbe things are breaking off the hydrogen the carbon is going to have to go somewhere.... unless they're bonding it into a solid carbon form (diamonds or graphite or such) then it's going to be into CO2 or similar. Not exactly a huge leap forward in environmental friendliness.

  • Security Blankets (Score:1, Flamebait)

    by pipingguy ( 566974 )

    Finally, a good use for cell phones!

  • Most excellent! (Score:3, Funny)

    by debilo ( 612116 ) on Sunday April 24, 2005 @04:31PM (#12331763)
    I need this, the amount of unwashed dishes and dirty laundry lying around could turn my entire apartment into a megastore of cheap energy!

  • Please use standard units (Score:4, Funny)

    by Anonymous Coward on Sunday April 24, 2005 @04:31PM (#12331769)
    less than the amount required to power a standard cell phone

    What is that in Libraries of Congress per Electronic Arts business day?

  • The blurb doesn't mean much (Score:5, Insightful)

    by Rosco P. Coltrane ( 209368 ) on Sunday April 24, 2005 @04:32PM (#12331775)
    The amount of electricity needed for the process is less than the amount required to power a standard cell phone.

    To power what? A 100-gallon microbial fuel cell or a very teensy one?
    • Word. "Less voltage" is not the same thing as "less power".
      • the 0.25 v is the potential drop per hydrogen atom produced. it scales. a 100 gallon reactor would have the same potential drop as a 1 gallon reactor. the cost scales too. just multiply atoms per second * 0.25v / 1.6e18 (atoms/coulomb). you dont need to know the current just the voltage and you can compute the power per volume.
    • RTFA (#2) -

      However, giving the bacteria a small assist with a tiny amount of electricity -- about 0.25 volts or a small fraction of the voltage needed to run a typical 6 volt cell phone -- they can leap over the fermentation barrier and convert a "dead end" fermentation product, acetic acid, into carbon dioxide and hydrogen.

      Logan notes, "Basically, we use the same microbial fuel cell we developed to clean wastewater and produce electricity. However, to produce hydrogen, we keep oxygen out of the MFC and

    • ACTUALLY, BLURB is accurate! just think. (Score:5, Informative)

      by goombah99 ( 560566 ) on Sunday April 24, 2005 @06:02PM (#12332363)
      A zillion posts here say that stating it uses 0.25v without stating the power used is meaningless. Well it's not. Well actually it's not what wou need to know. more on this in a second.

      Hydrogen is produced when the bacteria exchanges a proton for an electron at the anode. The proton becomes the hydrogen.

      thus it is one for one. For every hydrogen produced you have one electron dropping through a 0.25v external potential.

      If other processes are also transferring protons then that's still hydrogen. So one electron passed means some proton contianing species ended up on the electrode. as long as you can make sure that those are mainly hydrogen and not some weird thing (say a metal or sodium or soduim), then you dont care.

      So basically its a 0.25 volt cost atom produced.

      Now to the numbers: One mole of electrons is the same as 96,500 Coulombs. So producing 96,500 would require about 25 kilo joules of energy. A mole of hydrogen, if I recall correctly, contains 280KJ of energy of which 230KJ is extracable as work (rest has to to to heat to pay the boltzman tax).

      Of course the bacteria can also produce hydrogen on it's own. THe problem is the build up of reaction products that shut down the process. the current is used to help the bacteria get rid of these so the reaction can go to completetion producing hydrogen. Thus if I read this right in steady state we are indeed exchaning electrons for each hydrogen. The problem would then be if the bacteria is instead exchanging electrons for methane or something we dont want.

      I cant quite figure out the abstract of the science paper [acs.org] but it sounds like they get about 80% of what they want.

      • So basically its a 0.25 volt cost atom produced.

        Ah... here's the cause of the confusion. What we have here is 0.25 electronvolts per hydrogen atom produced. The electronvolt is a well-known quantity of energy commonly used in nuclear and particle physics, and 0.25 eV is about 4 x 10^-20 J. Multiplying by Avogadro's Constant, that comes to about 24,000 joules per gram of hydrogen, as you said, and I'll take your word for it on the rest.

        • that comes to about 24,000 joules per gram of hydrogen

          Assuming you're right, using that number we can compare the cost of getting energy from hydrogen obtained via this method vs. the cost of using the energy without going through this method (in other words, its efficiency).

          24000 joules per gram means 150 grams per kWh. A quick google search says H2 is good for 39kWh/kg, so with that 1kWh you'd get .15kg of H2 which in turn gives you 5.85kWh of energy out. huh?

          I'd appreciate someone doublechecking my

  • Slashdot articles ambiguous, rice says. (Score:5, Insightful)

    by rice_burners_suck ( 243660 ) on Sunday April 24, 2005 @04:34PM (#12331788)
    I really love the way articles on Slashdot's front page have a tendancy to be written in such an ambiguous way that the reader learns nothing from the article. Behold this excerpt from the present article:
    Environmental engineers at Penn State University and a research scientist at Ion Power Inc. have created an electrically-assisted microbial fuel cell that can be used to produce hydrogen from organic material. The amount of electricity needed for the process is less than the amount required to power a standard cell phone.
    It doesn't state how much hydrogen is produced. Are we discussing one molecule of hydrogen? (I know hydrogen is an element, but it floats around in the form of molecules.) And how much electricity is needed to power a cell phone? Are we talking about a fully-charged cell phone battery that becomes completely discharged? The description in this article doesn't tell you if:
    • One hundred thousand megatons of hydrogen are produced by less energy than is required to power a cell phone for one nanosecond.
    • One molecule of hydrogen is produced by less energy than is required to power a cell phone from the moment it is activated with a completely charged battery until the moment it shuts off because its battery becomes completely discharged.
    This is what I love about Slashdot articles.
  • Canyonero!
  • Will people be able to buy microbe tanks to generate hydrogen for their own homes? Imagine every home in the world adding to the hydrogen generating infrastructure. All of a sudden fuel cell cars would be a viable venture. Want wheels? Just add sea monkeys!
    • You'll need tanks, proton exchange membranes, electricity and some sort of feedstock. Plus compressors or cryo coolers, pumps etc.

      Maybe someone will package it all up into a handy wee box. Or maybe with the increasingly rapid advancements in battery technologies it'll be easier to just plug a battery vehicle into the mains, or the solar panel you have on the roof of your house.


  • Maybe the key phrase in one of the TFAs is "electrically-assisted".

  • Sigh... (Score:5, Insightful)

    by Gorath99 ( 746654 ) on Sunday April 24, 2005 @04:38PM (#12331825)
    The amount of electricity needed for the process is less than the amount required to power a standard cell phone.

    And what does that say? Nothing. I'm pretty sure I can create a couple of hydrogen molecules with that amount of electricity too and I won't even need any bacteria in the process.

    Here's a more useful bit from the article, though it would be even more useful if they would just say what fraction of energy this process requires:
    The voltage is just one-tenth needed for electrolysis - the process that uses electricity to break water down into hydrogen and oxygen.
  • Uhhhh. I haven't cleaned my room in a while. Yeah, I know those are half-eaten spaghetti bowls. Just don't light that cigarette in here, ok bud?

  • What's the point? (Score:2, Interesting)

    by TMonks ( 866428 )
    Is this supposed to be a cheaper way of cleaning wastewater, a more effecient way of creating hydrogen for fuel cells, or some combination of both? The article never really goes in depth on exactly why these bacteria are so good.
    • i'm suprised to see the only one comment like this! Indeed, why use microbes when we have a lot of stuff to create energy. One advantage of microbes is that they're ubiquitous and actually are able to metabolize everything. But how much biomass will we need to power a cell phone? Tons??

      • Re:What's the point? (Score:3, Interesting)

        by Nutria ( 679911 )
        But how much biomass will we need to power a cell phone? Tons??

        If it's not very efficient from an hydrogen-generation POV, just think of the hydrogen as a beneficial by-product of the waste-water purification process.
  • Scientists Use Microbes to Produce Hydrogen


    What a gas! ;P
  • hope this developes into cheep fuel technology for cars.
  • So why aren't we applying the same kind of thinking to power generation? 40% efficiency, 60% "waste" heat, at a couple of hundred C.

  • wanna see? (Score:4, Informative)

    by xlyz ( 695304 ) on Sunday April 24, 2005 @04:48PM (#12331904) Journal
    here [psu.edu] they are
    • I love the peanut butter jar tech, I also love the comment that it requires .25 V, which is just tiny fraction of 6V. For that matter its an even smaller fraction of the 25,000 V in my TVs flyback transformer. I get that .25 V is small but at how many amps? .001 mA, or 1000kA the pouwer requirement is vastly different. On the other hand this could be a neat way for cities to deal with sewage.

  • Volt != Watt (Score:4, Insightful)

    by Tharkban ( 877186 ) on Sunday April 24, 2005 @04:50PM (#12331921) Homepage Journal
    Did the Volt turned into a unit of power while I was sleeping? And I thought I did well in physics.

    • Or Volt != Ampere (Score:2, Interesting)

      by karvind ( 833059 )
      From the article:

      However, giving the bacteria a small assist with a tiny amount of electricity -- about 0.25 volts or a small fraction of the voltage needed to run a typical 6 volt cell phone -- they can leap over the fermentation barrier and convert a "dead end" fermentation product, acetic acid, into carbon dioxide and hydrogen.

      I agree, it is written poorly.

    • Re:Volt != Watt (Score:3, Interesting)

      by Dachannien ( 617929 )
      According to a commercial for a widget you can use to jumpstart your car through the cigarette lighter, the volt is a unit of energy. Said the commercial:

      Your normal car battery only has 12 volts of energy [person places multimeter leads on car battery, and the readout says 12 volts]. But the {insert product name here} has 48 volts of energy!

      Another classic was the commercial for the ion-producing air filter that said their product filtered dust out of the air because it was electrostatically charged...

      • Man, you actually made me feel dumber reading your post. 48 volt battery charger? Really??? If they can build a box that small that has that much more power in it, WHY AM I DRIVING A GASOLINE-POWERED CAR???

        Heh. I guess it's not funny. OTOH, I used to have one of those battery chargers, and they are pretty handy. Not as handy as carrying a real car battery around, but a lot safer than carrying a real car battery around.

        Speaking of stupid flashlights, I actually received as a Christmas present one yea

    • "Hey Ihr da Ohm, macht doch Watt Ihr Volt!"

  • read the full study (Score:5, Informative)

    by xlyz ( 695304 ) on Sunday April 24, 2005 @04:52PM (#12331934) Journal
    pdf with the original paper here [wustl.edu]

  • Meaningless comparisons: "less than a cell phone" (Score:5, Insightful)

    by G4from128k ( 686170 ) on Sunday April 24, 2005 @04:53PM (#12331941)
    The less than the amount required to power a standard cell phone statement is totally meaningless because it gives no indication of the efficiency of the process. Even at "0.25V", if the process requires tens or hundreds of electrons per molecule of hydrogen, then the process may be horribly inefficient. Even the "produces four times more hydrogen than would be typically generated by fermentation alone" is meaning less without some facts such as the molar conversion efficiency -- how many moles of hydrogen per mole of acetate does the augmented process create?

    Moreover, this process is not the holy grail of pure electrolysis (e.g., splitting water into hydrogen and oxygen), it is an electrolyticly augmented chemical conversion of carbohydrates into carbon dioxide (green house gas), water, and hydrogen. In theory, this process could by part of a biomass-to-hydrogen fuel generation cycle, but as we have seen with ethanol production, the amount ethanol-based energy harvested is poor in comparison with the energy required to grow, reap, and process the plants (corn).

    Don't get me wrong, this is a very intriguing finding, but there is far too little information in the article to determine if this process is thermodynamically better or worse than simply burning the carbohydrates in a furnace or standard combustion engine.

    What frustrates and saddens me is that the analysis needed to make useful statements about this discovery are not that hard to make. Any competent chemist or chemical engineer could provide a useful back-of-the-envelop estimate of the energy inputs and outputs given an afternoon with the raw data from the experimenters. Either the scientists involved did not do this analysis (shame on them) or the journalists chose to ignore key results (shame on them) or the actual return on energy input is very poor indeed (to bad for all of us).

    I hate articles that quote meaningless comparisons and leave the true question of practically total unanswered while holding out a vaporous promise that our energy problems are solved.

  • Fuel... cells? I don't understand (Score:3, Informative)

    by mcc ( 14761 ) <amcclure@purdue.edu> on Sunday April 24, 2005 @04:54PM (#12331942) Homepage
    A Fuel cell [wikipedia.org], if I am not mistaken, is a device for storing hydrogen and extracting electricity from hydrogen once stored.

    However the linked article talks about "fuel cells", but then talks about this "fuel cell" as producing hydrogen-- as if for some kind of process that would be used to produce hydrogen for use in fuel cells.

    What am I missing here?
    • That's exactly what this is (if worded incorrectly). This is a hydrogen creator, for fuel cells.

      A good example of how this could be used in the real world:

      Instead of gas tanks, we carry around tanks full of dense wastewater. Using something like this as a converter (if it was fast enough), it would allow us to have the benefits of fuel cells, without the storage problem (Hydrogen being a gas).
    • Well, conventionally, a fuel cell is merely the device that can utilize hydrogen to produce electricity. Fuel cells do not store hydrogen at all, they rely on a another device to store or produce the hydrogen. Typically, that will be a compressed gas or liquid H2 tank in the case of storage or a natural gas or methanol reformer in the case of production. I agree that the article is a bit misleading. But the way I interpreted it, they are using the hydrogen produced by the bacteria "real-time" as oppose

  • Minor nit (well hidden in article) (Score:1, Informative)

    by Anonymous Coward
    The process also produces good old CO2. You know, that nasty greenhouse gas. Not the environmentally friendly solution that it is spun as.

    Interesting research, but until the CO2 problem is solved it still needs work.
    • It's producing CO2 from biomass. Which means that carbon was recently pulled out of the atmostphere via matabolic processing in plants. This process can be a part of a sustainable carbon cycle.

      CO2 is not evil and is required at certain levels to maintain the climactic balance and sustain biological cycles.

      Digging vast amounts of formerly sequestered carbon out of the earth and injecting it into the atmosphere is where the global warming greenhouse effect is coming from. This process doesn't seem to do th
  • or even better yet
    Microbes use hydrogen to produce scientists.

  • Actual Paper Link (Score:5, Informative)

    by cowtamer ( 311087 ) on Sunday April 24, 2005 @05:18PM (#12332090) Journal
    The actual paper referenced is Electrochemically Assisted Microbial Production of Hydrogen from Acetate [acs.org] by Drs Hong Liu, Stephen Grott, and Bruece E. Logan from Penn State, in the publication "Environmental Science and Technology."

    Enjoy...

  • hrmph (Score:3, Funny)

    by _ph1ux_ ( 216706 ) on Sunday April 24, 2005 @05:21PM (#12332103)
    "scientists use microbes to produce hydrogen"

    Lazy scientists. Wont somebody please think of the microbes.

  • Hmm (Score:1)

    by rezon ( 878573 )
    Mr. Fusion!

  • Considering recent news... (Score:3, Interesting)

    by MsGeek ( 162936 ) on Sunday April 24, 2005 @06:01PM (#12332350) Homepage Journal
    ...this is good if it pans out. Considering how Global Peak [hubbertpeak.com] Oil [lifeaftertheoilcrash.net] might have been already reached, or if not, we're close to it, we're going to be needing a replacement for petroleum and soon.

  • vague. (Score:2)

    by pyth ( 87680 )
    "The amount of electricity" - would that be amps, volts, or watts?

    "Less than the amount required to power a cell phone" - really now, and even if I scale up the process by a factor of 10, it will still take the same amount? AMAZING!
  • Almost every wastewater plant you see has a big flame stack in the back where they burn off the excess methane not used for heating the biomass or the building. It seems to work quite well, so why don't we just convert that to electricity or put it in gas mains?

    Is this process inherently more efficient in producing hydrogen instead?

  • Bah (Score:4, Insightful)

    by susano_otter ( 123650 ) on Sunday April 24, 2005 @08:56PM (#12333212) Homepage
    Totally missing from the article, and the abstract:

    Does the process produce as much fuel as is necessary to fuel the process? More? Less?

    What's that you say? The article cleary states that this process is cheaper than the old process?

    Great! But is it cheap *enough*?
  • I don't see how suing microbes over the JPEG patent is going to produce energy for anyone but lawyers.

    Whoops! Misread that headline.

  • microbial batteries (Score:4, Funny)

    by anthony_dipierro ( 543308 ) on Sunday April 24, 2005 @09:25PM (#12333319) Journal

    Environmental engineers at Penn State University and a research scientist at Ion Power Inc. have created an electrically-assisted microbial fuel cell that can be used to produce hydrogen from organic material.

    Combined with a form of fusion, the machines have found all the energy they would ever need.

  • "0.25 volts" is not a measure of power (Score:3, Informative)

    by the_REAL_sam ( 670858 ) on Sunday April 24, 2005 @09:59PM (#12333487) Journal
    Volts x Amps = Watts.

    Electricity is measured in watts. That is why your electric bill is measured in watts. (and not volts.)

    The article did not tell us enough to determine whether there had indeed been a boost in the ideal efficiency of hydrogen production.

    If it had said 1 watt and 1 lb of lawn clippings had been used by the microbes to store 1 kilowatt hour's worth of hydrogen then that would be pretty interesting. For those who care.

    "0.25 volts" could be measuring 0.25 volts at 30 amps or at 1000 amps. The article didn't mention amps. And even if it had, it didn't tell us how much hydrogen was generated. Nor did it tell us what percent efficiency the reaction had been. Nor did it give us a comparison between microbial hydrogen production's efficiency and that of standard electrical electrolysis.

    Anyhow, perhaps there was a genuine breakthrough, but the article doesnt describe enough to get me excited.

  • Why isn't the hydrogen and helium produced at nuclear waste sites harvested and used commercially. Especially the Helium. It's my understanding that eventually we'll run out of helium since it's extracted from oil wells, being the product of long years of radioactive materials releasing alpha particles.

    Would it be excessivly expensive to harvest the stuff from nuclear waste sites? They have to have some kind of allowance for offgassing due to the buildup of flammable hydrogen. Why not build somthing to sit

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