I live in the midwest and our electricity primarily comes from coal. Unlike gasoline cars, burning coal emits mercury, which then falls into rivers and lakes, and is then absorbed by aquatic plants that are then consumed by fish, which are then consumed by eagles, bears, and people. Because the mercury stays in the organism until its death/decomposition, the animals higher on the food chain end up with higher and higher amounts of mercury than the organisms they consume. The ecological damage of coal goes beyond the greenhouse gasses.
We don't have smog in most places around here. Plus, we have roads that are real fun to drive on.
See why this idea horrifies me?
This is one of the problems with the utilitarian model. People in the big cities have this or that problem and then the country folk have to suffer because population-wise, we're the minority. Our problems are different and we generally require less regulation rather than more.
I get that there are good intentions behind the regulation, but I don't think this is the way to do it. If California wants to get the ball rolling on green energy and reduce smog then they should invest more into hydrogen fill stations, push bivalent hydrogen cars, and build more trains. I see a future of electric cars as just another problem -- it could massively increase energy costs, possibly cause supply problems (leading to more coal burning) and, hell, they're no fun to drive.