Well, the thing is, if you're buying it for environmental reasons, you need to look how your energy is being generated. If you live in the US, for example, about 70% of your electricity is being produced from coal, so there goes the benefit. In other countries with a higher percentage of energy generated by more environmentally friendly means, EV's may be more suitable.

In any case it's a complicated issue. I spent literally years researching alternative fuels, both for environmental and economic reasons. Looks for forums on EV's, hybrids, etc. You will find a lot of good information on the subject.