[sexy_ninja_goat]

This would only work in a small percentage of places that receive enough sun throughout the day/year to power a large bank of batteries that would then, in turn charge the car at night when you're in bed. Photo-voltaic tech is still so expensive, I don't want to even guess at what a solar panel covered car port w/battery bank costs..... (Ok I'll guess... As much as the car you are parking in it.)

I think it's great they're testing the tech as it's the only way to improve it enough to make it practical and affordable.

However, it's still not going to be practical for the parts of the world that have more seasons than just summer, which makes it impractical for car manufacturers to really invest too heavily (very small market share if you look at geography limitations + people that can afford new vehicles (never-mind a BMW) + cost of maintenance/replacement on battery banks, solar panels, and car batteries).