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Power Science

Using Sun's Energy to Split Water Means Solar Power All Night 557

phorm writes "Reuters is carrying an article about a recent MIT development which may pave the way for solar-energy to be collected for use in low-input periods. According to Reuters, the discovery of the a new catalyst for separating hydrogen+oxygen from water requires only 10% of the electricity of current methods. This would allow storage-cells to function as a form of battery for other forms of energy-collection, such as solar panels. The new method is also much safer (and likely environmentally friendly) than current methods, which require the use of a dangerously caustic environment, and specialized storage containers." sanjosanjo points out coverage of the process at EE Times, which features the MIT group's press release.
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Using Sun's Energy to Split Water Means Solar Power All Night

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  • by pwnies ( 1034518 ) * <j@jjcm.org> on Thursday July 31, 2008 @06:05PM (#24425357) Homepage Journal
    "...with our catalyst almost 100 percent of the current used for electrolysis goes into making oxygen and hydrogen."

    If that is true (although I definitely have my doubts, as tales and empty promises of the past have made all of us highly skeptical when we read something like this), then it should open the road for a significantly more efficient means of producing hydrogen for hydrogen powered cars / devices. Hell a car equipped with a solar cell could just bake during the day to recharge itself and be ready to go for the commute home come 5pm. Though until I hear a confirmation of MIT's findings from another university/respected source, I hold on to my severe doubts about this.
    • by mpoulton ( 689851 ) on Thursday July 31, 2008 @06:19PM (#24425525)

      "Though until I hear a confirmation of MIT's findings from another university/respected source, I hold on to my severe doubts about this.

      MIT isn't really in the habit of making unsubstantiated claims of new discoveries. That's pretty much the purview of startup companies in need of funding and no-name universities looking for grants. MIT et al stake their reputations on their discoveries, and do not generally cry wolf.

      • by lgw ( 121541 ) on Thursday July 31, 2008 @07:22PM (#24426179) Journal

        Extraordinary claims demand extraordinary proof. In any case, you don't let any researcher (or institution) off the hook because of his popularity - what kind of science would that be?

        • by ssintercept ( 843305 ) <ssintercept@nOSpaM.gmail.com> on Thursday July 31, 2008 @08:26PM (#24426867) Journal
          that would be ...popular science...you know thet got a magazine and all.
        • by phorm ( 591458 ) on Thursday July 31, 2008 @08:44PM (#24427027) Journal

          I tend not to believe MIT because of their "popularity" so much as because of their "reputation."

          The latter could be rather heavily damaged by making unsupportable claims in regards to their research.

          Not that we shouldn't wait to see this in action, but at the very least I'll be waiting eagerly to see these experiments repeated in a controlled environment.

          • Re: (Score:3, Funny)

            by sir fer ( 1232128 )

            I'll be waiting eagerly to see these experiments repeated in a controlled environment.

            I had a mental image there of the "uncontrolled environment" of MIT labs...blow...hookers...party hats...whistles...liquid nitrogen...

        • Wrong (Score:5, Insightful)

          by Anonymous Coward on Thursday July 31, 2008 @10:39PM (#24427997)

          > Extraordinary claims demand extraordinary proof.

          No, extraordinary claims require ordinary proof that has been vetted extraordinarily well.

          Otherwise, someone can arbitrarily declare claims 'extraordinary' and simply raise the bar every time the proof meets their old standard. You know, like they do with global warming, or evolution.

          Sorry, but that soundbyte just gets to me.

        • by Cutie Pi ( 588366 ) on Friday August 01, 2008 @08:56AM (#24432659)

          But these claims really aren't as extraordinary as you might think. They've found a new catalyst that reduces the amount of energy required to split water. That's what catalysts do--they reduce the activation energy of a reaction. Life would not function without catalysts. Every enzyme in your body (there are thousands of them) is a catalyst designed to make some reaction run efficiently at body temperature.

          Every few years a breakthrough catalyst is discovered that makes new reactions feasible. See for example the Grubbs' catalyst [wikipedia.org] which when discovered had almost magical properties compared to the state of the art. Grubbs recently won a Nobel prize for this work.

          Currently, platinum is a catalyst on the cathode, for generating hydrogen. This works well and has been known for a long time. This new research has found a useful catalyst for the anode, which generates the oxygen.

          While this might be a major breakthrough, I don't find it to be extraordinary, at least in the same sense that a self-sustained cold fusion reaction is extraordinary. These results should be easy to duplicate in other labs as the materials are straightforward.

      • by Sycraft-fu ( 314770 ) on Thursday July 31, 2008 @07:44PM (#24426367)

        For one, professors have to get grants to do their research, so they are sometimes given to overstatement to that end. They are, after all, only human which means that not all of them are honest. Also, some are simply unrealistic. They think they can do something, so they announce it, even though they have no idea how to get there, and then maybe never end up doing so. Finally sometimes shit just ends up being impossible. It looks good, seems like things will work, however in the end you can't make it happen. That happens with research. You can spend millions only to realise you've been down a dead end and there's nothing to be done about it.

        I agree an announcement from a major university is much more credible than some startup, but don't think things out of universities aren't overstated at times.

        • by Alpha830RulZ ( 939527 ) on Thursday July 31, 2008 @07:46PM (#24426397)

          See, for example, the claims on cold fusion some years back.

        • Re: (Score:3, Interesting)

          by FirstOne ( 193462 )

          "For one, professors have to get grants to do their research, so they are sometimes given to overstatement to that end. They are, after all, only human which means that not all of them are honest. Also, some are simply unrealistic. They think they can do something, so they announce it, even though they have no idea how to get there, and then maybe never end up doing so. Finally sometimes shit just ends up being impossible. "

          I think this is for real, they've reduced the Voltage needed to split w

      • by Gibbs-Duhem ( 1058152 ) on Thursday July 31, 2008 @09:34PM (#24427461)

        Indeed, Nocera has been working on this for what must be at least 15 years by now. I remember he had some catalysts four or five years ago that worked using only the ambient intensity of sunlight, but were far too expensive to be practical (so I heard).

        I also work in catalysis, and one of my friends is doing water splitting, so I've read a few papers on the topic. The materials used don't surprise me, cobalt is approximately as good as you can find. Also, I would note that this catalyst (I downloaded the paper) is releasing oxygen and gradually producing HPO4, which can then later be oxidized to (presumably) release energy. I'm not familiar with using phosphoric acid as a fuel, but the paper sounds extremely plausible.

        I would also suggest that, based on my reading of the paper, any real world applications would be 5-15 years away, depending on how well they're able to coat their electrodes.

    • Re: (Score:2, Informative)

      by Delwin ( 599872 ) *
      The volume to power of hydrogen is still far too low compared to batteries. Otherwise this could be the breakthrough that finally gets fuel cell cars going - self regeneration of (some) power during the day.
    • by getnate ( 518090 ) on Thursday July 31, 2008 @06:22PM (#24425563)
      'nuff said.
    • by mapsjanhere ( 1130359 ) on Thursday July 31, 2008 @06:33PM (#24425687)
      There is the slight question of where and how you store your hydrogen and oxygen in the meantime so, especially for small scale "localized" applications.
      Lets say your house needs 5000 W. To get through an 8 h dark period, you need 40 kWhr, or 136,000 BTU. That's roughly the energy in 2 lbs of hydrogen. To store that much hydrogen, you either need a balloon of 11 m^3 size, or you need a compressor that allows you to store the hydrogen as compressed gas (what costs energy to do) or to liquefy the hydrogen (what costs even more energy). Alternatively you can adsorb the hydrogen into certain alloys, but then you need to heat them to get the hydrogen back out, again ruining your energy balance, and driving up the cost.
      This development can help with the development of a large scale hydrogen infrastructure, but there we're better of with natural gas (of which we're not running out anytime soon, and which has much less technological hurdles in storage).
      • by Anonymous Coward on Thursday July 31, 2008 @06:47PM (#24425823)

        Why not just leave it stored as water, then, and electrolyze it as needed?

        • Re: (Score:3, Funny)

          by Thiez ( 1281866 )

          Dude.

          1) The hydrogen is used to generate power.
          2) To electrolyze water you need power.
          3) You suggest we use power that has already been stored *somewhere* to electrolyze water and then use the hydrogen to generate power.
          4) Laws of thermodynamics.
          5) ???
          6) Profit.

      • by Anonymous Coward on Thursday July 31, 2008 @06:51PM (#24425863)

        Lets say your house needs 5000 W.

        Let's not. That's more power draw than the total available service into most houses; and most houses don't exactly draw at max for 8 hours straight. Divide your numbers by 5, and you have a more reasonable estimate.

        • by Anonymous Coward on Thursday July 31, 2008 @07:06PM (#24426001)

          Let's not. That's more power draw than the total available service into most houses;

          Where do you live? Afghanistan? I live in a Central American country with crappy electricity and this house is often drawing way more than 5000 W. There are eight computers running, two refrigerators, a large freezer, four air conditioners, a heater in the pool, an electric stove, washer, dryer, and much more.

          • by modmans2ndcoming ( 929661 ) on Thursday July 31, 2008 @07:10PM (#24426053)

            And they say Americans are energy hogs?

        • Re: (Score:3, Informative)

          by maeka ( 518272 )

          Lets say your house needs 5000 W.

          Let's not. That's more power draw than the total available service into most houses; and most houses don't exactly draw at max for 8 hours straight.

          The smallest house service panel I have ever seen (by far) was a 50 amp one. 50 amps X 240 volts (U.S. uses split-phase) = 12,000 watt service.

      • Re: (Score:2, Interesting)

        by Carnildo ( 712617 )

        There is the slight question of where and how you store your hydrogen and oxygen in the meantime so, especially for small scale "localized" applications.
        Lets say your house needs 5000 W. To get through an 8 h dark period, you need 40 kWhr, or 136,000 BTU. That's roughly the energy in 2 lbs of hydrogen. To store that much hydrogen, you either need a balloon of 11 m^3 size, or you need a compressor that allows you to store the hydrogen as compressed gas

        Eleven cubic meters is no big deal -- that's a balloon a

        • Strange but my math shows a sphere with radius .75 meters to have a volume of about 1.75 cubic meter. You'd need a radius of around 1.39 to achieve 11 cubic meters...

          So, a baloon almost 9 feet across. Not so small. Not huge either. But then the original poster said a house needs 5000W.. that's an incredible amount. Cut that in half, and you can cut your baloon in half too. Just don't do it while it's full!

        • Re: (Score:3, Informative)

          by Thiez ( 1281866 )

          Huh?

          Volume of a sphere: 4/3 * pi * r^3

          d = 1.5.
          -> r = 0.75

          V = 4/3 * pi * 0.75^3 ~= 1,8 m^3

          Your math is correct when we assume a sphere with a radius of 1.5 m (in that case V ~= 14.1 m^3), but that means we are talking about an orb with a 3 meter diameter, which is heigher than most ceilings (3 meters = 9.8 ft for the SI-impaired).

      • There is the slight question of where and how you store your hydrogen and oxygen in the meantime so, especially for small scale "localized" applications.

        You pump water uphill during the day. Then at night, you let it fall downhill and generate electricity from that. We don't need fancy chemical tricks or storage mechanisms to make sporadic energy sources produce constant outputs.

        • by inKubus ( 199753 )

          Pump an bunch of water, what could possibly go wrong? That might have worked in the middle ages but solar power demands efficient storage. There isn't enough to go around as it is, and you want to burn it moving tons of water? What about the pump's efficiency? What about the friction in the pipes? In the words of Samir Naehninejhad: Tom, this idea, this is horrible.

          Surely a frictionless flywheel [wikipedia.org] is the most efficient, currently (no pun intended) viable solution. A number of vendors, such as Beacon En [beaconpower.com]

        • Spin up a flywheel during the day. Compress air in a tank during the day. Charge a lead-acid battery during the day... etc
    • by HTH NE1 ( 675604 )

      "...with our catalyst almost 100 percent of the current used for electrolysis goes into making oxygen and hydrogen."

      Hopefully there's enough other current to compress that oxygen and hydrogen into pressurized tanks for recombination.

      Yes, both. I'm not keen on letting either of them build up in free air to explosively combustible concentrations in my garage.

    • I have my doubts because it's a supposed big breakthrough on more than one front. First, the electricity needed is supposed to drop by roughly an order of magnetude over existing industrial methods, and I'm always a bit skeptical of such big gains.
      But more probably, it's over-hyped because it also eliminates 'specialized storage containers' (as the summary puts it, not exactly what the article says, but it seems fairly close). Taking out some or even all of the caustic substances industrial e

    • Well, hydrogen + oxygen + fossil fuel is said to be far more efficient, cleaner, and cooler burning than fossil fuel alone.

      According to additional research productized by MIT, for gas engines, it's said to increase efficiency 30% and diesel engines are said to improve 50%. Furthermore, their head guy claims that's the tip of the iceberg. Sorry I don't have the link but likely someone else will know what I'm talking about. It was researched by MIT, spun off into a company, which was purchased by another comp

    • by maeka ( 518272 ) on Thursday July 31, 2008 @09:00PM (#24427183) Journal

      Hell a car equipped with a solar cell could just bake during the day to recharge itself and be ready to go for the commute home come 5pm.

      People often fail to realize the great energy density of gasoline and the amount of solar energy which hits a small area (such as the footprint of a car.)

      My Honda accord has a footprint of 7 square meters.
      IIRC the amount of solar energy reaching the Earth's surface at noon, at the equator is 1KW per square meter.
      Assume a 8 hour work day, 50% efficient solar panels (better than current best), 100% efficient splitting of water and 1KW per square meter all the working day long.
      That gives you 28 kilowatt hours worth of energy = 100,800,000 joules.
      A gallon of gasoline contains 130,000,000 joules.
      0.71 gallons of gas.

      A more realistic scenario taking into account actual insolation (not my wacky 1KW the entire 8 hours) and the latitude most car owners live at gives us more like 400 watts per square meter (assuming you tilt the panels appropriately), 50% efficiency, 8 hours = 11.2 kilowatt hours = 40,320,000 joules = 0.31 gallons of gasoline equivalent.

      Not only are there not many drivers who could commute on such little energy, the economic value of such small amounts would take a long time to offset up-front costs of the system.

    • by MagusSlurpy ( 592575 ) on Thursday July 31, 2008 @09:14PM (#24427315) Homepage
      Dan Nocera is one of the top ten names (American, anyway) in this field right now, and he has been working on this with several of the others (such as Jay Winkler and Harry Gray [wikipedia.org]). I've sat through probably 10 of his seminars at American Chemical Society conferences in the last two years, and he was pretty close in April (and seemed really excited about a new development, too). My guess is that he's spent the intervening time repeating the experiments, to guarantee it works. And as to corroborating sources, I'm sure that his cohorts from CalTech, etc. are double-checking everything, too.

      Anyway, I guess where I was going with this is that this isn't some fuel pill, or Al Gore rambling on about things he doesn't understand. Nocera is to water splitting what Miyamoto is to video games, and if he says that he's done it, I'm sure he's done it.
  • Wow (Score:5, Funny)

    by Anonymous Coward on Thursday July 31, 2008 @06:10PM (#24425413)

    First open sourcing solaris and now this.

    Way to go Sun!

  • by StefanJ ( 88986 ) on Thursday July 31, 2008 @06:13PM (#24425441) Homepage Journal

    This would be a big win for any kind of "environmental" energy source (wind, waves, caged toddlers) that isn't always on.

    Heck, it would make a great general-purpose home UPS and/or load leveler. If properly integrated, a home equipped with this would be less vulnerable to brownouts and blackouts. Local storage would make the job of power companies easier too.

    Fingers crossed.

    • by Dice ( 109560 ) on Thursday July 31, 2008 @06:32PM (#24425677)

      >This would be a big win for any kind of "environmental" energy source (wind, waves, caged toddlers) that isn't always on.

      Perhaps you've never seen a collection of caged toddlers. I assure you, they are always on.

      • Re: (Score:3, Informative)

        Not to mention, have you seen the waste products? I wouldn't call 'em "environmentally friendly"!

        I have a toddler, trust me on this. ;)

        • Scrape the contents of those Huggies into a biodigester and reap big $$$ in methane sales!

        • by falconwolf ( 725481 ) <falconsoaring_2000@yah o o .com> on Thursday July 31, 2008 @08:48PM (#24427053)

          Not to mention, have you seen the waste products? I wouldn't call 'em "environmentally friendly"!

          Actually the way the waste is treated now it's unsustainable. However it would be sustainable if that "waste" were composted and made into humanure [wikipedia.org]. If you garden, depending on what you grow in the garden, your plants will love you for watering them with your urine. Not straight mind you, nitrogen burn can kill them, but by mixing 10 parts water to one part urine. They would also love it if they were watered with greywater [wikipedia.org]. That's what I did for a while, my bathtub was clogged for a while before the owner sent a plumber. So I'd use the grey water from showering to water my garden. Those who have commented about the garden said it looks real good, another gardener asked how I got my tomato and tomatillo plants so big.

          Falcon

      • by hitmark ( 640295 )

        unless your not looking ;)

  • If this is true... (Score:5, Interesting)

    by quantum bit ( 225091 ) on Thursday July 31, 2008 @06:19PM (#24425519) Journal

    What are the implications for things such as water purification, desalination, etc?

    Seems like a fuel cell "battery" is just the tip of the iceberg.

  • by YesIAmAScript ( 886271 ) on Thursday July 31, 2008 @06:21PM (#24425551)

    Now we only have to solve the problem of storing a very flammable gas and possibly an incredibly powerful oxidizer!

    • by hitmark ( 640295 )

      dont we already know how?

      only problem is that being the smallest atom out there, hydrogen loves sneaking out of any storage tank, given time...

      • 'Given time' isn't much of a problem. You only need to store the energy overnight for this kind of system. Even if you lose a little bit to leaks, it's still a lot better than burning oil. It's not just for home use either - a lot of power plants adjust to consumption quite slowly and so would benefit from a more efficient way of storing surplus power.
  • by Brynath ( 522699 ) <Brynath@gmail.com> on Thursday July 31, 2008 @06:22PM (#24425567)
    "For the last six months, driving home, I've been looking at leaves, and saying, 'I own you guys now,'" Nocera said.

    Scientist and Gamer...

  • by SuperBanana ( 662181 ) on Thursday July 31, 2008 @06:25PM (#24425591)

    According to Reuters, the discovery of the a new catalyst for separating hydrogen+oxygen from water requires only 10% of the electricity of current methods

    Great. So when do we see it? If it's anything like almost every other "alternative energy" advancement, it will either get snapped up by an oil-company owned holding company, or strangled by licensing fees/requirements/exclusivity deals.

    Seriously- let's take a look back. Have there been any major advancements in solar energy technology in the last fifty or so years?

    MIT = MIT Technology Licensing Office, and I used to work there. Six figure checks to professors were not uncommon...and it was the only part of the university that turned a profit.

    It'd be really refreshing to see scientists develop a bit of altruism. It's the ultimate Open Source, and they'd be guaranteed decades, if not centuries, of good will and fame. That's worth a lot more than a few *possible* royalty checks.

    • Re: (Score:2, Insightful)

      by maxume ( 22995 )

      Have there been any major advancements? I'm don't know, because I have no idea what major means to you, but the costs have come way, way, way, way down, and they continue to get lower.

      Hell, solar panels even net energy these days.

    • by bucky0 ( 229117 ) on Thursday July 31, 2008 @06:53PM (#24425875)

      >> It'd be really refreshing to see scientists develop a bit of altruism. It's the ultimate Open Source, and they'd be guaranteed decades, if not centuries, of good will and fame. That's worth a lot more than a few *possible* royalty checks.

      Altruism neither pays for the scientists' mortgages nor pays for all the equipment they use to develop their theories.

      I'm all for smacking down ridiculously-long copyrights, invalidating silly trademarks or getting rid of obvious patents (one-click shopping?), but this is the _exact_ thing that patents is supposed to support. These scientists (and by proxy, their granteurs (sp?)) took a gamble on developing a technology and they were successful. They should be rewarded for that success like any other person in society. Without that potential for gains, there's no reason to even try.

    • So when do you plan to start doing your job for free?

    • Since 1958? (Score:4, Informative)

      by zogger ( 617870 ) on Thursday July 31, 2008 @07:28PM (#24426233) Homepage Journal

      50 years ago was 1958. Interestingly enough., that was the year the first solar panels went to space. Today, you can sit right there in your chair, do some googling, whip out your credit card and have dandy solar panels shipped right to your house at less than NASA cost plus pricing levels. That's pretty significant. A few years previous to that, some of the first ones were running $1,785 dollars per watt, and those are unadjusted dollars. Today you can look for deals and get them at around 5 bucks a watt. Not too shabby. And nanosolar started shipping this year, albeit all of it to Germany where demand is higher and they will pay a bit more now, because they know conventional will be going up fast later, so they did a whole nation push for it starting some years ago. That and it is cleaner.

      here's the wiki ref for the figures, Solar timeline [wikipedia.org]

      I bought mine at actually a little under 5 bucks a watt some years ago. silicon demand has been going more for throw away gadgets and so on in the meantime, but several new fabs go online this year and next year so prices will be dropping again.

  • "Nocera's catalyst is made from cobalt, phosphate and an electrode that produces oxygen from water by using 90 percent less electricity than current methods, which use the costly metal platinum."

    Ok wait, I looked it up and we're currently at 70% efficiency on the electrical energy it takes to split water. I believe we lose even more power to compress the gas in to liquid form for storage.

    Now let's say we're only at 10% efficiency now on electrolysis. If you decreased the amount of electricity needed
  • Well it seems like Prof Nocera [mit.edu] has chosen to keep his paper off the internet, or at least his research group's publications list. [mit.edu] His invention has already been patented, so that's not the reason. Why is that while academics in physics, maths, and engineering are busily posting copies of their papers or preprints on their websites or arxiv [arxiv.org], chemistry academics almost never put up online copies of their papers? It seems like a poor way to go about communicating cutting edge science to me.
    • Chemistry is where the real money is.

    • Re: (Score:3, Informative)

      by Falstius ( 963333 )

      The paper is being published in a journal that comes out this week. It wouldn't make sense for him to post it to his website before it is even published (and would probably be a breach of contract).

      Although MIT press releases are notoriously pie-in-the-sky, there probably are some real improvements here.

  • by evwah ( 954864 ) on Thursday July 31, 2008 @06:41PM (#24425761)
    I can't believe that this hasn't been tagged "vaporware" yet
  • by Repton ( 60818 ) on Thursday July 31, 2008 @06:52PM (#24425865) Homepage

    It is established FACT that Hydrogen is very difficult to contain. It leaks through the tightest seals like they were swiss cheese, and once free it races into the atmosphere and escapes into space.

    This is not a major problem when all our hydrogen comes from the deep deposit hydrogen mines in Australia and Canada, but what if this new discovery hearalds an age of wholesail water mining? Do these so-called scientists not realise that we cannot have water without hydrogen? Have they forgotten that humans are 80% water? That water makes our crops grow and our fish swim?? Our life's blood could be literally floating away!

    This irresponsible god-gaming may save us from peak oil today, but our grandchildren tomorrow will be facing PEAK WATER if these experiments are allowed to continue!

    Write to your political representative today!

  • Sun?!?!? (Score:3, Funny)

    by Darkness404 ( 1287218 ) on Thursday July 31, 2008 @06:52PM (#24425871)

    Using Sun's Energy to Split Water Means Solar Power All Night

    Well perhaps using Sun's energy is easy for you, but for those of us who don't live close to Sun's headquarters, it is impractical to buy a 100 mile long extension cord.

  • by Goldsmith ( 561202 ) on Thursday July 31, 2008 @07:04PM (#24425971)

    If you read the actual article (you need to be a AAAS member or otherwise have access to Science), you would see that that these MIT guys are using a cobalt oxide catalyst which is created during the electrolysis of water. Yeah, it's really efficient, which is good (I don't know that I buy the green thing), but it's also self-repairing. Although it seems to be future work, they're envisioning tailoring the chemistry so that the activity of the catalyst is maintained by an equilibrium of dissolving and redeposition of the catalyst electrode. As a bonus, it looks really easy to make.

  • This seems very interesting and I hope it goes well for them. But I can't help but feel there are simpler solutions.

    Any excess electricity inserted into the grid during the day could be used to run electric motors that turn pumps and push water up a hill (or tower) which we need anyway. During the night if power is needed simply run it back down the hill through the pumps which turn the electric motors and generate electricity for the grid. And water my lawn!

    I realize there is quite a bit of efficiency loss

    • Re: (Score:3, Informative)

      What do you mean "would work"? It's been working for a long time. The British did this thirty years ago [wikipedia.org]. I'm sure there are other similar systems elsewhere in the world, too.

      The two main problems with these schemes are that the capacity is quite limited - you run out of water in the high-altitude reservoir - and getting the response time down to small numbers of seconds requires energy input (you can't just let all the water in at once with the turbines stationary, since that would damage the bearings

    • Conservation? (Score:3, Insightful)

      by copponex ( 13876 )

      This seems very interesting and I hope it goes well for them. But I can't help but feel there are simpler solutions.

      Yeah. How about using less stuff? It works 100% of the time, is 100% effective, anyone can do it, it uses current technology, and you can start right now. Sure, I love computers. But I only have one. I like TV, but I decided to save money and just watch shows through the web instead of getting cable and buying a TV. I love driving my car, but I try not drive unnecessarily. (As a side benefit I was able to cancel my gym membership and get exercise and commute at the same time.) I like steak, but I only eat r

      • Re: (Score:3, Interesting)

        by TooMuchToDo ( 882796 )
        The crucial problem is that in economics, and the world economy as a whole, success is measured in growth. What should be measured is your environmental footprint along with your revenue to determine the sustainability of your business. Just because you can churn out a million widgets a year doesn't matter if you're tearing down the Amazon to do it.
  • by Ungrounded Lightning ( 62228 ) on Thursday July 31, 2008 @08:07PM (#24426653) Journal

    The solution is touted as improving storage of renewable energy from fat hours for use in lean hours. That problem is already well in hand using various battery technologies. I doubt that, even with this improvement, electrolysis-gas storage-fuel cell will beat even lead-acid batteries, let alone lithium ion (with efficiences close to 100%) or stationary vanadium redox (with properties like fuel cells but storing the energy in tanks of liquids at atmospheric pressure).

    But it may be a DANDY solution for providing hydrogen and oxygen for powering vehicles: (fuel-cell prime-mover hybrids, hydrogen internal-combustion (at a carnot-cycle penalty), etc.) or as feedstock for energetic chemical processes.

    • by ceoyoyo ( 59147 ) on Thursday July 31, 2008 @09:29PM (#24427423)

      Why would you want to provide hydrogen for powering vehicles if you've got such great batteries?

      Because batteries aren't so great. They're only reasonably efficient when they're nice and warm, they're heavy, they're expensive, and they wear out fast.

  • by nyet ( 19118 ) on Thursday July 31, 2008 @08:19PM (#24426791) Homepage

    clicky [nyet.org]

    So we don't go with this mimic-of-the-biologicalstuff
    approach, at least for hydrogen. Dan Nocera
    and Nate Lewis organized a Gordon Research Conference
    on solar fuels in 2007 that assessed all the
    inorganic, nonplatinum hydrogen catalysts around.
    Three winners came out. One is a dimolybdenum
    system that Dan DuBois at the Pacific Northwest
    National Laboratory has worked on, and one is a
    cobalt system that Vincent Artero and Marc Fontecave
    at the Université Joseph Fourier in Grenoble,
    France, developed. The third was originally developed
    at Iowa State in the 1980s by Jim Espenson
    [BS '58], was recently improved by Xile Hu when
    he was a postdoc here at Caltech, and is now
    being worked on in my lab by grad student Jillian
    Dempsey. The DuBois molecule and the Caltech
    one are both very good. They operate at very close
    to the optimum voltage to make H2. This is a critical
    feature, because if the system's voltage is more
    than the optimum, the extra energy is wasted. And
    if the voltage is insufficient, the reaction doesn't go
    at all. But Dan's molecule contains sulfur, which
    can be nasty, and ours is easier to make, so we
    think the Caltech one looks like a real winner.

  • other use for o2 (Score:3, Interesting)

    by bxwatso ( 1059160 ) on Thursday July 31, 2008 @09:22PM (#24427369)
    I don't think you have to keep the O2 to run a fuel cell; won't it run off the O2 in the air? I suspect that the O2 would be tanked and sold to hospitals and industrial uses. Also, it might be more cost effective to pipe/truck the H2 to the city to operate a fuel cell there, thereby reducing the electrical loss from long distance transmission and step-up / step-down transformers.
    Indeed, it might be best to convert all solar power to H2 and truck it to the city vs. building expensive transmission lines and pipelines.
  • by Doc Ruby ( 173196 ) on Friday August 01, 2008 @12:05AM (#24428651) Homepage Journal

    The Reuters article claims the new catalyst drops the conversion inefficiency by about 90% compared to platinum. Since platinum efficiency is about 50-70%, that means that the new efficiency is about 95-97.5%.

    This is an incredible advance, if it's true. Even though it increases the efficiency of only the oxygen generation, leaving hydrogen still generated by a platinum catalyst at the old efficiency. Even if the efficiency has jumped only from 50-70% to about 70-85%, that's still a big jump. And it shows that there's a lot of reachable gains left to get, and not necessarily in the distant future.

Think of it! With VLSI we can pack 100 ENIACs in 1 sq. cm.!

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