With the solar system from Solar Electrical Vehicles (SEV), the Toyota Prius can operate up to 20 miles per day in electric mode thus improving fuel economy by up to 29% (depending on driving habits and conditions). SEV is the sister company to the oldest and largest systems integrator of solar power systems in Southern California, Solar Electrical Systems, and it is specialized in adding a true solar charging system to hybrid cars like the Toyota Prius. That’s not only green, it looks very cool, too.