The catch is that the current technology isn't all that efficient. It only converts about 6.5 percent of the energy it gets, which pales in comparison to the 22 percent you see among the world's better solar panels. If the creators can improve the performance of this graphene-coated cell, though, they could have a dream solution on their hands -- you wouldn't have to live in a consistently sunny part of the world to reduce your dependency on conventional power.