On Mon, 25 Jun 2012 22:08:16 -0500, Ignoramus6950
wrote:

I was thinking about electric cars today.

An internal combustion car, burns fuel inside cylinders and produces
energy according to Carnot cycle. Say, it makes 28% of energy from the
total BTU of fuel that it burns.

Compare it with an electric car. A coal electric power station
operates at efficiency of 33% (Wikipedia).

Then 10% of this is lost in power distribution.

More lost in stepping down line voltage to 220 volts.

Further, more is lost in a battery charger.

Then more is lost in the car battery.

Then more heat is lost in motor windings and power semiconductors.

This is probably by far less efficient than internal combustion an
distribution of gasoline!

And how is it going to reduce CO2 emissions, if more CO2 needs to be
burned as coal than would come from gasoline?

i
The only way it really "saves" anything is with hydro power, solar,
wind, or atomic. Possibly Natural gas.