One advantage of the electric car is that it can be charged at 'off peak' hours, making best use of the electricity generating plant. Just like having a pumped water storage hydro electric station does... it's a means of storing energy in times of plenty to make up for times of high demand.
An electric car is much more efficient (at source) in terms of energy required to propel the vehicle a given distance: electric motors are over 90% efficient, gasoline engines are up to 30% efficient and diesel engines are around 40-45% efficient.
The power station is around 30-35% efficient
Whilst a majority of our electricity comes from pollution-generating sources, electric vehicles move the pollution from the cities to the countryside and do not seem to offer a significant reduction in CO2 emissions. Obviously, if the electricity came from an environmentally friendly source, then electric cars DO offer genuine reductions in CO2 and other pollutants
I would be interested to see the FULL 'life cycle costs', both financially and environmentally, of an electric car, a similar sized gasoline car and a similar sized diesel car. I think that would be interesting reading
The same argument could be put foreward for "zero polluting" hydrogen powered cars - produce your hydrogen from an environmentally friendly source and it's great.....
As far as I see it, the most efficient and practical (in terms of range, performance, etc) alternative vehicle propulsion would be a diesel-electric hybrid system.