> I have no idea how much power is required to generate hydrogen, but I do
> agree that a hybrid car like the Prius fitted with super efficient solar
> panels is probably the best approach in the short term. It could trickle
> charge the batteries while parked in the sun.

     Part of me hates to contribute to this off-topic thread, but I just
can't stand by while the misinformation flys back and forth rampantly.

  >>> Solar cars <<

     A solar car is typically 6 feet wide and 20 feet long and covered
with solar cells.  These high-end solar cells typically cost over
$100,000. They generate, at most, two HP.

     Bottom line = Solar cells are a foolish way to power a car and they
always will be. Your typical small sedan needs about 15 HP on the
highway to maintain speed. Since your car is only 13 ft long and about 7
feet wide, you can't collect the power you would need to commute, even
with the most efficient (and expensive) solar cells. Do the math for
yourself and you will see for yourself. It make much more sense to
simply plug the car in when it is parked.

  >>> Two good approaches <<<
     There are two sensible approaches: Electric cars and biodiesel

hybrids.

  >>> EVs <<<

     With off-the-shelf technology, you can easily build an EV that will
go 250+ miles on a single charge and will have sports car performance.
http://www.acpropulsion.com/ACP_tzero/SEMAtrip2003.htm

     If you need to fill up quickly, Toshiba just came out with a Li-Ion
battery that you can charge in less than a minute.
http://www.toshiba.co.jp/about/press/2005_03/pr2901.htm

  >>> Biodiesel <<

     Biodiesel pollutes much less than regular diesel and is less
expensive per gallon. It has a closed carbon cycle so it does not
contribute to global warming. You can put it in any modern diesel car
without modification.

    Details on  emissions:
http://www.epa.gov/otaq/models/analysis/biodsl/p02001.pdf

     General information: http://www.globalstewards.org/biodiesel.htm

  >>>> "Fool" cells (bad idea) <<<

     Fuel cell cars make no sense. Once you take the time to "do the
math" this becomes clear. Making hydrogen is a lossy process.

If you make hydrogen from electricity, then put the hydrogen in a
fool-cell car, it will go half as many miles as an electric car that you
simply charged with the same amount of electricity. The fool-cell car
will also cost twice as much as the EV.

A 200 mile range fool-cell car will weigh more than a 200 mile EV with
Li-Ion batteries.

If you make hydrogen from natural gas, the fool-cell car will not go as
far as a hybrid car running on the same amount of natural gas. The
fool-cell car will cost much more than the hybrid car.

You will have to replace the membrane in the fool-cell about every
50,000 miles (perhaps even more often.) You will have to replace the
battery pack in the fool cell car about every 100,000 miles. (The
battery pack in a fool-cell car is the same size as the one in a hybrid
car.)

You will not be able to refill your fool-cell car rapidly. If a
high-pressure storage is used, it will take about 15 minutes to fill the
hydrogen tank. If metal hydrides are used, it will take more than 30
minutes to fill the tank. Modern EVs can fill much more quickly. (I
routinely charge my electric drag bike in less than 12 minutes.)
http://www.killacycle.com

  Fool-cell cars were a very clever diversion away from alternative fuel
technologies that really work. The present administration backed
fool-cells because:

A) At first glance, they don't pollute (until you look into where the
hydrogen comes from, and how much you will use.)

B) All the hydrogen would be made from fossil fuels.(That is the most
economic source.)

C) You would use twice as much fossil fuel per mile than other
alternative fuel technologies.

D) They could suck the money out of all the other alternative fuels
research programs and throw it down a black hole.

E) The car makers knew that they would never have to re-tool to make
them because they are impractical and always will be.

Off my soap box and back to airplanes now. :^)

Bill Dube' (my personal, but well-researched, opinions)

Hi Bill,
I was suggesting that solar cells be used as complimentary charging device
in climates where it would benefit. Of course you would still have to rely
mainly on the engine to generate electricity.
   My main beef however is that an alternative fuel such as bio-diesel
could have been produced and gradually implemented over a period. Instead
Governments have done virtually nothing, even though they knew we would face
an oil crises eventually.
   There is no doubt the oil companies are profiteering (at least in this
country) from this crises and at the expense of the ordinary person. Yet
Governments seem powerless to do anything. I wonder why??.
Ok lets get back to aircraft engines, can we run a rotary on bio-diesel?/
Michael

OK guys this has nothing to do with rotaries.

Paul Lamar