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Scientists Use Microbes to Produce Hydrogen

Posted by Zonk on Sun Apr 24, 2005 04:27 PM
from the free-as-in-beer dept.
Power Science
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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[+] Microbes Churn Out Hydrogen at Record Rate 168 comments
FiReaNGeL writes to mention that Penn State Researchers have improved on their original microbial electrolysis cell design bringing the resulting system up to better than 80 percent efficiency when considering all energy inputs and outputs. "By tweaking their design, improving conditions for the bacteria, and adding a small jolt of electricity, they increased the hydrogen yield to a new record for this type of system. 'We achieved the highest hydrogen yields ever obtained with this approach from different sources of organic matter, such as yields of 91 percent using vinegar (acetic acid) and 68 percent using cellulose,' said Logan. In certain configurations, nearly all of the hydrogen contained in the molecules of source material converted to usable hydrogen gas, an efficiency that could eventually open the door to bacterial hydrogen production on a larger scale."
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Scientists Use Microbes to Produce Hydrogen 50 Comments More /

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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: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"...
    • 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!

    • 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.

  • Most excellent! (Score:3, Funny)

    by debilo (612116) <shegez@gmailBOYSEN.com minus berry> 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.

        • Do you think a 100 gallon fuel cell is likely to operate on the same potential difference as a small one?

          It's a question of size (i.e. spacing between electrodes) rather than power. The original poster asks a valid question.

          And the poster to whom you replied makes an accurate observation as well. If there is a conductive path between the fuel cell's electrodes then probably the larger the cell the greater the conductance (lower the resistance). This means in order to keep the applied voltage up to the

    • 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.

  • 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.
    • From the article -

      Using a little amount of electricity - about 0.25 volts - scientists at Pennsylvania State University found that a microbial fuel cell can overcome its "fermentation barrier", Xinhua reports.

      The voltage is just one-tenth needed for electrolysis - the process that uses electricity to break water down into hydrogen and oxygen.

      ...and...

      The voltage to be given, scientists explain, is a small fraction of the voltage needed to run a typical six-volt cell phone.

      RTFA next time. The head
      • Power is not voltage alone. And like you mentioned, it doesn't at all state the amount of hydrogen created or whether the efficiency is high enough that more energy isn't consumed in the production than is able to be used from the resultant hydrogen. Regardless, I suppose it's good news; increased efficiency is increased efficiency.

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

      by mchawi (468120) on Sunday April 24 2005, @04:42PM (#12331852)
      I agreed with your statement, but I thought I should check Google to see if I could find any information - just out of curiosity. At the time I posted this, I found 8 total articles. The thing that scared me even more was that all of the articles are similar in whole or in part. It looks like most of them probably just printed up a press release.

      Does it scare anyone else how lazy our news media has gotten? Couldnt these people even make one phone call and try and add anything slightly new, different, or informative that everyone else doesn't have?

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

      by MojoRilla (591502) on Sunday April 24 2005, @04:46PM (#12331889)
      Complain about Slashdot all you want, but the articles and the original press release [psu.edu] are all missing the details you want. This is a case where the only details that have been reported have been gleaned from a press release, only published two days ago. It will take a while before a journalist asks the kind of questions you want asked.

      Slashdot is not a news site. There aren't a group of reporters doing fact checking. It is new aggregation and community site.
    • Ok. In academia, there are a couple kinds of articles.

      1) News articles: "We make clean energy."
      2) Academic articles: "X-Amount of Hydrogen, from bacteria a, in quantity b, with y about of power."

      They'll publish their results in a reputable academic journal. It's publish or perish. This is just the candy article for the press. If you're really interested in the details, look at the author's pubs. If it's not there, check up in a couple months. He won't leave it that way for long.

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

      by twelveinchbrain (312326) on Sunday April 24 2005, @05:31PM (#12332162)
      It doesn't state how much hydrogen is produced. Are we discussing one molecule of hydrogen?

      According to the abstract [acs.org]:
      This bio-electrochemically assisted microbial system, if combined with hydrogen fermentation that produces 2-3 mol H2/mol glucose, has the potential to produce ca. 8-9 mol H2/mol glucose at an energy cost equivalent to 1.2 mol H2/mol glucose.
  • 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?
  • 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.
      • 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.
  • 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.
    • 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...
    • "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?
    • 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

  • 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.

  • 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.

  • 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*?

  • 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.

    • Re:YES!!! (Score:5, Informative)

      by fyngyrz (762201) on Sunday April 24 2005, @04:44PM (#12331873) Homepage Journal
      Probably not. Tap water contains all manner of stuff besides h2o. And since the hydrogen results from splitting the h from the o, that basically will leave you with a (tank|filter|general miasma/encrustation) of calcium, nitrates, bacteria, various metallic oxides, chlorine products and worse. The oxygen you might be able to use, but then again, maybe not.

      You'll be splitting distilled water just like the rest of us, matey, and leave the tap water going down the drain. :-)

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