If you do the math, solar powered cars are not going to work. You just don't have the available surface area on a car to provide enough power to charge it in a reasonable timeframe. Plus solar panels add weight and manufacturing complexity. If you're building an electric car you would be better off spending your time trying to make the car more aerodynamic or weigh less. The only way I could see it working in a production vehicle is with an rv that can have its panels fold out while stationary. Any investor worth their salt could do 10 minutes of math and figure out that this is a terrible idea.