"Franz wrote in message after me...
[snip]

Much more efficient to burn the hydrogen in a reciprocating (or
rotary)
engine than to convert it through a fuel cell to run an electric
motor,
though electrically propelled vehicles do have the potential to
convert
the slowing down process back into usable power.

Totally wrong, and ever heard of regenerative braking,

Evidently he had, as evinced in the paragraph you described as "totally
wrong".


The rotary engines we have developed have all proved less efficient in
practice than the old reciprocating engine (check fuel consumption) which
is why only Mazda persist with them and then in only one vehicle in their
range. Controlling pollution from them has been a major problem too.
Fuel Cells (chemical batteries) are much more efficient at converting
chemical energy to electricity than burning it in any way, be it steam
powered turbines or reciprocating engines. It's why it is expected that
Power Generation will follow the Fuel Cell route idc.

As far as regenerative braking is concerned he mentioned Electrically
Propelled Vehicles, I've not seen a normal coach powered in such a way.
Normal diesel engined coaches have had brake generators for years.

--
Regards
Bob

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