In Virginia, we have a couple of nuclear plants that supply much of our base load. Nukes need to be run at a steady power, so it is common to use the nukes for the steady base and fossil fuels for the varying loads, which are typically high during the day. In that power situation, plug-in electrics, charged overnight, make some sense.
Solar charging is tempting, but if your car is at work and not at home when the sun is shining, somewhat of a myth. There are solar electric car packages being sold, but the strategy is more of an offset, supplying solar power to the grid, not your car, during the day, and using grid power at night for charging.