response 68 of 91:

Oct 28 21:28 UTC 2006

Is there some route you can take which does not require driving 65 mph?
Heating just makes use of some of the large percentage of energy being wasted
by the engine, which converts most of it to heat not motion, so it should not
affect fuel efficiency in a gasoline-powered car.  One of the problems of
electric cars is that people want them to be heated.  One solution is a
propane heater.  Cars are poorly insulated, and not designed to conserve heat.