I currently have a large array of solar power panels on my home, and my intent is to purchase a Prius and install the mod http://www.edrivesystems.com/ as soon as it is available. It adds some batteries and allows you to plug in and charge your Prius while in your garage. This drastically increases the fuel efficiency. In my particular case, where most of my car trips are nearby around Berkeley, very little gasoline or any will be used. And since my electrical power is generated by my solar panel and not power plants, very clean.

I fully expect that this will not be very economical. My roof PV system was only economical because I got in just under the wire with some Calfornia incentives. However, I feel that supporting these efforts will hopefully make them more economical in the future.