Bill Babcock wrote:
> I love this kind of stuff.
> http://www.technologyreview.com/articles/rnb_030804.asp?trk=nl
>
> Makes you realize that some of the really persistent problems (like what are
> we gonna do when we run out of dead dinosaur juice) may not be all that big
> of a problem. And the solutions might be very prosaic. A fuel injector and a
> catalyst to make hydrogen from ethanol, and a fuel cell to convert it to
> electricity. Hmm, no noise, portable, potentially cheap fuel, pure water
> from the fuel cell as a byproduct. I wonder what comes out of the H2
> converter. C2H5OH goes in, but I don't know anything about catalyzed
> reactions like this.
The company for which I worked, until it was cast into the depths of the
globalization ocean by its owners, had a
long-term fuel-cell project. There is one element you only partially describe
in the above that's the principal
problem--a reactor chamber to convert ethanol (or methanol) to hydrogen. This
thing gets gummy with carbon residues and
needs repetitive maintenance. Otherwise, the system is fairly sound, except for
the issue of energy exchange.
Catalytically stripping the hydrogen from ethanol or methanol is a net energy
loss--those C=H covalent bonds that are
broken to release the hydrogen don't contribute to the motive process--it's
only done because the fuel cell can't use
ethanol or methanol directly. And, if the reactor maintenance isn't done, the
fuel cell eventually quits working.
Reactors to date don't perfectly exchange the carbon in ethanol or methanol to
CO2.
The energy exchange ratio/emissions output using straight ethanol with a
catalytic converter is probably nearly equal to
that of a fuel cell, without extraordinary changes in current technology.
Don't get me wrong--hybrid-electric technology today is maturing, and
direct-electric fuel cells are going to be here to
stay. But, if there's a net loss of energy conversion efficiency, then the
demand volume of ethanol and methanol
required will far exceed the supply, and the fuel costs will be exorbitant.
The other issue today is long-term maintenance costs. Traditionally, internal
combustion engines are maintainable with a
rather low investment on the part of the owner. That historical reality will
get turned on its head with this
technology, which will require a level of training at dealerships unheard of in
the past, and the replacement parts
costs will be fierce. The difference between maintaining a fuel cell vehicle
and an internal combustion engine will be,
at current costs, about a factor of eight or nine, perhaps dropping to a factor
of three or four in a decade or two.
Much of that is directly due to the control circuitry, which is expensive to
diagnose and repair. I suppose there may be
volumetric improvements there, but what I've seen to date doesn't seem
encouraging regarding costs.
Ultimately, the real answer is, near-term, alternative fuel vehicles using
modified current technology and/or
hybrid-electrics running on either gasoline or alternative fuels, and in the
long term, a much better national mass
transit system, combined with all-electric vehicles powered from grids supplied
by solar/wind/biomass generators.
As for vintage racing, as I've previously suggested, relaxation of the rules to
allow the use of naturally-derived
ethanol or methanol in combination with digital fuel injection will go a long
way to preserving the sport in the next
decade or two, when the public consciousness will be focused on diminishing
resources. Fuel injection will improve
mileage, and using bio-fuels from plants which fix CO2 will be a selling point
for racing clubs which will inevitably
find themselves under attack in the next decade or so.
Cheers.
--
Michael D. Porter
Roswell, NM
Never let anyone drive you crazy when you know it's within walking distance.
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