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On Tue, 3 Jul 2007 15:46:01 -0400, Evan Osler <[log in to unmask]> wrote:

>The internal combustion engine is horribly inefficient relative to an
>electric motor and battery. Shifting the location of energy production to a
>centralized grid gives the typical electric car an equivalent efficiency of
>easily 100 mpg (likely much more than that).

Got a source for that 100 mpg?  I don't think it's true.

It's been a while but I did take an engineering class on energy and power.
Sure electric *motors* are efficient, but first you have to convert fuel
into electricity.  An internal combustion powered car delivers an energy
efficiency of something like 25% when you are driving down the road.
Power plants (coal, oil, gas) do something like 35-40%.  So better than
internal combustion, but not dramatically so.  Then you have to ship the 
electricity over power lines and lose 10%.  Then you lose 10% in the motor.
So you end up with a total efficiency in the lower 30's.  This does not
translate to an equivalent 100 mpg.

Of course, at idle, an internal combusion engine does nothing, other than
power the AC.  That's where hybrids are great, as pointed out by Jerm.

Correct me if I'm wrong, 

Mig

>
>As the electric grid gets cleaner over time (hopefully), one could expect
>this level to go up. In a state like Vermont, with a very clean grid
>already, an electric car is an extremely low-impact ride.
>
>I do agree that the useability of the electric car needs to go up, which it
>is with advances in battery technology. In the meantime the hybrid system 
is
>a smart middle-ground. Plug-in hybrids are next (get your first ~100 miles
>per tank on battery alone if you choose to plug in). In the long term, the
>individual auto model will have to become outmoded anyway.
>
>Ethanol is virtually worthless to America in its current form, and don't
>believe any politician who tells you otherwise.
>
>-eo
>
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