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This discussion relates to Technology Review's article Solar-Power Breakthrough.

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  rr999999999
  

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  08/01/2008 12:18 PM

  Storage

  Hydrogen is absolutely not viable for residential storage.  This has to be a commercial endeavor.  The EEstor ultracapacitor, if it comes to realization, would be a dream come true.  Very little infrastructure would be needed.  Weight and Size would be greatly reduced.
  

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    vv111y
    

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    08/01/2008 02:14 PM

    Re: Storage

    Has anyone considered large scale, municipal sized ultracapacitor installations? If I've got it right, none of the materials are rare, and there is no reason that an ultracapacitor cannot be scaled up arbitrarily large.

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      cjameshuff2
      

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      08/01/2008 03:18 PM

      Re: Storage

      Current ultracapacitors have nowhere near the energy density of other load leveling technologies like pumped hydroelectric or flywheel storage. They can be charged and discharged quickly (though more slowly than other capacitors), but really can not store much energy. They have enormous capacitances compared to other technologies, but extremely limited voltages, and since energy stored is given by 0.5*C*V^2...a 10 farad capacitor charged to 2.5 V stores only 32.25 joules, enough to give a bit over half a watt of power for one minute. A 0.1 microfarad capacitor at 25 kV stores the same amount of energy...this is a voltage that is commonly exceeded by color CRT monitors.
      
      That's why nobody's seriously considered it yet. EEStor is doing something entirely different, though. Rather than building electrolytic capacitors with carbon aerogel electrodes to get the high capacitance, they are building high voltage capacitors with bariam titanate ceramics, using high purity materials with some special processing techniques to achieve both high capacitance and high operating voltages. They have not yet released a working product or, to my knowledge, even demonstrated a working prototype, but they've apparently impressed Lockheed Martin...hopefully they've got something.
      
      Whether it'd be possible to scale it up for load balancing of grid power is another issue. It requires high purity barium titanate, which is not rare, but not overwhelmingly plentiful or cheap either. And again, there's alternatives like pumped water, flywheel, and thermal storage that are in current use and can be scaled up to very high capacities.

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    darthwilliam
    

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    08/01/2008 03:47 PM

    Re: Storage

    Storing and moving pure hydrogen is prone to problems - leakage, low energy density, etc. I have not seen anyone suggest taking this apparent low-cost way of making hydrogen and using that as input to a sabatier reaction which combines H2 with C02 to produce CH4. Sabatier as I understand it is a well known easy reaction. Combined we now have a way to make carbon-neutral 'natural' gas. And that we have infrastructure for distributing and storing already, without the problems of pure hydrogen.
    
    Just an idea.
    
    ...darth

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    pascal1960
    

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    08/01/2008 05:37 PM

    Re: Storage

    So why not just connect your hydrogen producing solar-powered system to the tank of your hydrogen car?  If the system is inexpensive to build, maintain, etc., but large storage at home is a problem, why not just install it for your vehicle at home?  No more gas stations... 
    This is an open question from a non-engineer...

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  Phineas
  

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  08/01/2008 12:27 PM

  Work For Fuel Cells?

  Can this break-through catalytic process be used to reduce the cost of fuel cells? The other half of the equation.

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  mithram1
  

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  08/02/2008 04:01 AM

  Congratulations.

  Renewable Energy Centre, Mithradham (www.mithradham.org )is the first fully solar educational instituion in India dedicated for the promotion of environment and renewable energy technologies. Our centre is working with solar energy for the last 9 years. The solar system is a stand alone system. We are using a gel battery bank for storage. When can we expect the break through in storage in the market so that we could go for it when the battery life expires ?.
  

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  • 
    Cens
    

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    08/03/2008 06:45 AM

    Re: Congratulations.

    To produce oxygen Nocera and Kanan added Cobalt and Potassium phosphate to freshwater. Both Cobalt and Potassium phosphate exists natural in seawater. Is it likely that the process also would work simply using ordinary seawater without adding anything to it ?

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  Mr Frank
  

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  08/03/2008 09:22 AM

  news media

  If this was really such a breakthrough why did the major news medias  not pick up on it?

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  ted122
  

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  08/03/2008 03:59 PM

  Patent Number??

  Does anyone have the patent number for this invention?  Can't seem to locate it.  Or perhaps a paper describing the experiment.

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  • 
    gvo1000
    

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    08/04/2008 11:42 PM

    Re: Patent Number??

    I have done a quick search: no issued patent or published patent application at the US Patent & Trademark Office. It is possible and likely that an application was filed fairly recently. I know others who start calling their idea "patented" the moment they have filed, well before an actual patent is granted and issued. More hype, but in this case probably not consciously designed to mislead.

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