Re: Electric vehicles

The weight of the motor is only part of the picture. I think you want
to compare the cost per mile and the cost over 5 years for a gas car
and an electric car, each with a specified accel, hp, rolling friction,
and drag coefficient. People think power=speed, and its true that it
takes a lot of power at high speed, but all that big power is used for
acceleration. People think sports cars that can accelerate at about
..4Gs are 'peppy'. Two wheel drive cars are burning rubber at .5Gs.
Lambos and 4WD exotics that get sub 6 second 0-60 times are smoking all
4 wheels to get going that fast. I have a spread*** that shows you
can get 100mpg with a 1500lb car with a drag coeff of .25 (pretty
slippery) cruising at 44mpg. (This only takes 15 or 20hp). If you could
live with .2 or .3G accel, even a 20HP electric can run down the road
at hiway speeds.Turns out that 15 or 20 HP cruise power takes a certain
number of KW and the cost of gas and grid was about the same (using
$.12 per KWH). The electric was cheaper theoretically if you had your
own diesel generator in the back yard and could run the charger at $.06
per KWH. I assumed over 5 years, both cars need tires, insurance,
brakes, etc etc, so that stuff sort of cancels out.

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