"Edward W. Thompson" wrote in message
...
On Sun, 17 Jul 2005 10:25:49 +0100, "Dave Plowman (News)"
wrote:

In article ,
Edward W. Thompson wrote:
Yes. They'll be wonderful when we get renewable electricity. Which
will
probably be never. And burning a fossil fuel in a power station to
charge *any* battery is far less efficient than using that fuel
directly to power the vehicle.
snip

A COGAS system (Gas turbine with waste heat recovery) will have an
efficiency slightly better than 50%. A slow speed diesel with waste
heat recovery also will exceed 50% efficiency. Steam turbine system
that provide the bulk of power have efficiencies closer to 30%.

Yes. And add in transmission losses via the grid, etc, then the much
higher losses involved in actually charging any battery. Add in the costs
of any high tech battery throughout its likely life, and it makes far
more
sense to use that fuel directly - apart from any localised emissions
issue.

Nevertheless power generated with machines that are 50% efficient
using low grade fuel (heavy oil) is less 'expensive' than power from
an IC engine fitted to an automobile. I am assuming that the
emissions from the machines at central power stations are
appropriately treated.

Electric vehicles are more environmentally friendly overall with
respect to emissions than IC powered vehicles, however, whether they
are more economically viable, when all factors are taken into
consideration, is clearly open to debate. The economics/costs
associated with pollution are beyond me but are clearly very real.

The exchanges in this thread on what is a serious issue is would not
do credit to a ten year old.

I agree.