Ford's (NYSE:F) new C-Max Energi concept car is the first major vehicle to combine solar and electric powers to drive vehicles, opening up a world of possibilities for the future. The concept car has 300 watts of SunPower's (NASDAQ:SPWR) high-efficiency solar panels placed on the roof, which will nearly charge the vehicle's 21-mile range in a day. But what does the future bring for the combination of solar and EVs? 

Fool contributor Travis Hoium explains below that a vehicle like Tesla's (NASDAQ:TSLA) Model S could get 2,000 extra miles of range per year from adding a similar small solar array. That's power that's free and clear once the vehicle is purchased, and it doesn't require any effort to use. Such an easy energy source is revolutionary in the auto industry and opens up billions of dollars in opportunities for SunPower as well.