Ford is exploring solar charging with its concept car, the C-Max Solar Energi, which uses solar power to directly charge the plug-in hybrid's battery pack.
If you're hoping this car charges on the go, you'll be disappointed; it's still designed to charge when parked up.
But the concept is a unique one. Rather than plugging in your C-Max Energi each time you stop, you park below a special solar concentrator with Fresnel circular lenses. This magnifies the sun's rays onto the roof of the car, which is covered by solar panels.
The normal sunlight is boosted by a factor of eight, allowing the relatively small roof-mounted solar array of SunPower cells to gather enough light during a day's charging for a full battery top-up, or 21 miles of EPA-rated electric range.
It frees the car entirely from the need to charge via the electricity grid, though the Solar Energi retains its charge port so once you get home you can still plug it in and benefit from your home's solar panels. If you don't already have solar panels and charge via the grid, using the solar roof system could cut your grid charging by as much as 75 percent.
http://news.discovery.com/autos/fuel-and-alternative-fuel-technologies/ford-unveils-solar-powered-car-140102.htm