This should not surprise anyone. As long as the energy to charge the batteries used by electric vehicles is derived from fossil fuels, you're not really gaining anything. In fact, when you factor in how inefficient batteries themselves are and how many nasty pollutants are used in making all those batteries, you're probably doing more damage to the environment.
That doesn't mean electric vehicles should not be pursued, but it should put some perspectives on things. As always, there are pros and cons to everything.