Innovators around the world are obsessed with harnessing the power of the sun. Solar energy has been used to power lamps that light up the night, to run desalinators that create clean drinking water, and to offset fossil fuels on utility grids. But what about solar cars? The world hasn’t seen many sun-powered vehicles, but it’s not for lack of innovation or competition. In fact, many such cars have competed against one another in the…