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RE: [GreenYes] Scientific Breakthrough Liberates Energy Users from Fossil Fuel
Mischi-

I don't think anything in my earlier message implied in any way that
fuel cells do not work or that solar or wind power couldn't be harnessed
to produce hydrogen for running fuel cells.  My earlier message just
said that the particular device described in an EWIRE release cannot
possibly exist as described since doing so would violate the second law
of thermodynamics.   

Bob Kirby did post a follow-up message ("Fuel Cell Question" December
15th) in which he asks if fuel cells really are no more than a temporary
storage/utilization medium to take hydrogen produced by solar and wind
power and utilize it to make electricity. Since nobody else has replied
to Bob's comments, I'll add a comment or two, although I am not very
knowledgeable in this field.  

First though, a question to others.  Solar and wind power can be used to
generate electricity pretty directly.  I know you can produce hydrogen
by taking that electricity to electrolyze water.  Is there a more
efficient way of producing hydrogen from solar and wind power that does
not involve generating electricity (a fairly inefficient process)?  If
not, it of course would be more efficient to use the electricity
generated by solar or wind power directly than it would be to use the
electricity to produce hydrogen, which would eventually be consumed in a
fuel cell to produce electricity again.  The hydrogen then would be just
a temporary storage medium for the energy, although perhaps an
easier-to-store form than storing the electrical energy directly in a
battery for use in vehicles.

In response to another part of Bob's follow-up email, I checked with my
son (who is just starting as a graduate student researching fuel cell
technology) and he pointed out how fuel cells can make the generation of
electricity from hydrocarbon-based fuels more efficient and less
polluting than the current method involving directly burning the fuels.
Burning fuels usually results in no better than 35% efficiency, meaning
that 65% of the energy from the hydrocarbon fuel is lost as heat to the
environment.   However, you can pretty efficiently produce hydrogen from
hydrocarbon fuels by reacting them with water to produce hydrogen and
CO2.  If you could do such a conversion at 80% efficiency, and then
react the hydrogen in a fuel cell at better than 50% efficiency to
produce electricity, the net result would be more than 40% efficient -
better than direct burning.  In addition, you wouldn't get all the nasty
combustion byproducts such as NOx, polycyclic aromatic hydrocarbons, or
dioxins.

Comments from other more-knowledgeable people on this subject are
welcome.

Peter Spendelow
Oregon Department of Environmental Quality

-----Original Message-----
Date: Mon, 16 Dec 2002 15:56:39 EST
From: Heelsrnum1@aol.com
Subject: RE: [GreenYes] Scientific Breakthrough Liberates Energy Users
from Fossil Fuel 

Peter, You are right, and you are wrong. There is no perpetual motion 
machine, so you are entirely correct about the law of thermodynamics
(energy 
is never gained or lost, just changed into a different form). HOWEVER...
I 
don't want you to get misguided into thinking that fuel cells run on
hydrogen 
which was seperated from water through solar or wind (or some other form
of 
clean energy) is not possible. In fact, this technology already works.
-- If 
I were a carbon-pusher I would try and convince the environmental
community 
that there is no solution to creating clean, abundant and entirely 
sustainable energy for our country. But there is. It's all very simple 
science, if you want to understand it. -- If you do nothing else, read
THE 
HYDROGEN ECONOMY by Jeremy Rifkin. It explains the technolgy as well as
the 
politics behind it. ...............
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