Leonhardt said it would be more practical to use solar power to help charge a car's battery and use the more efficient panels mounted on a roof or over a parking area to supply the rest of the electricity needed to drive the engine.
The selling point of the E-rev is that is cuts out "range anxiety" because if the electric charge in the battery runs low the car can use petrol to generate more.
We can imagine the day when you'll be able to charge the battery on your plug-in hybrid car at night, because your smart meter reminded you that nighttime electricity is cheapest.