Thank you for your question.
Electric cars are very efficient compared to the cars most people drive.
Here is a very informative page on electric car emissions:
The Case for Electric Cars
You are correct in hypothesizing that the output from the plants
negates the lesser pollution from ethanol-fueled cars, to an extent.
It was previously thought that ethanol was very inefficient; however,
new studies have come out this year saying that ethanol is not as
inefficient as previously thought, is more efficient than regular
fuel, and is getting better with new technologies being developed.
Ethanol Study Released
As Hedgie pointed out, ethanol is ethanol, but there are different
ways of making this molecular compound. In particular, the Brazilians
use sugar to make ethanol, and their method of using sugar is much
more efficient than the American way of utilising corn. Americans
could support ethanol from sugar; it's quite a long story of why they
Sugar farmers in America get enormous federal government subsidies.
The price that farmers from other countries sell sugar is very low
compared to that of American sugar, so Americans would make no money
with sugar if they sold it at market value. They get huge subsidies
and sell sugar at a high price. Sugar from other countries is slapped
with huge tariffs, so that it cannot compete in the American market
with American sugar. Sugar is more expensive in America than most
countries in the world. If you travel to any other country and order
a Coca-Cola, it has sugar in it. In America, it doesn't; it has high
fructose corn syrup instead. HFCS is very unhealthy compared to
regular sugar, so this is not a good thing at all, except for the corn
farmers. Most processed foods in America do not have sugar but HFCS.
So, Brazil has cheap sugar and can make ethanol out of it very
effectively and at huge volumes. America would be helping the world's
environment by supporting the Brazilian sugar industry or at least
letting sugar in America fall to market rates and using it for ethanol
instead of corn, which is entirely inefficient. However, America has
chosen to pass specific laws charging large tariffs on Brazilian sugar
and Brazilian ethanol, which were supported by almost all
It is not clear that corn ethanol should be completely abandoned in
the US, though, because it can eventually be made a more efficient
electric car efficient
If you need any additional clarification, let me know and I'll be glad
to assist you.