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[GreenYes] Fuel cell question
re: Scientific Breakthrough Liberates Energy Users . . .

Peter Spendelow makes an excellent point regarding the above, and one that 
extends to all fuel cells.  Fuel cells have been integral to all of the talk 
about the potential for a hydrogen economy.  
Of course this "Scientific Breakthrough" was silly, for the reason Peter 
explained.  

But how about all of the discussion of "open system" fuel cells?

If you look at http://www.fuelcells.org/whatis.htm, you will see they say 
that when hydrogen is the input, water is the output of the fuel cell.  The 
whole economic question, as I've heard it, is in finding a clean low-energy 
way to separate water into hydrogen and oxygen.  But if water is the output 
of the fuel cell, then by thermodynamics, there is no net gain possible from 
the overall energy system.  It might make sense if the output from the fuel 
cell were some molecule at a lower energy level than water.  And no 
conversion process is perfect, so you don't even net out at zero.

So hydrogen by definition is nothing other than an energy storage medium?  
Maybe for solar or wind energy?  No more than that?  Can someone help me with 
this?

And if you use hydrocarbons as the input to a fuel cell, of course one of the 
outputs is carbon dioxide, right?  So it may be less polluting, but doesn't 
improve the greenhouse gas situation.

Can someone please explain why the above is not true?

Thanks.

Bob Kirby
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