Why doesn't Tesla make cars with a sun-roof with solar panels?

First of all, the Prius with the solar roof doesn't provide any power to the traction battery. Its main function is to run the HVAC fans while the car is parked on a sunny day to keep the interior from getting overly hot. read more

There are a few reasons why solar panels aren’t fitted on a Tesla sunroof but are used on a Prius. 1) The Prius solar panels are just being used to operate internal cabin fans to help keep the car cool and are there to ensure the 12V starting battery isn’t drained by these fans. read more

no need to go too far with the stealing assumption, etc. Rooftop solar panels are not someone's design. They are a very old concept and even serial ICE cars had sunroof fitted panels for powering ventilation (Audi A6, etc..).. Tesla really is too young of a company to have invented it all. read more

The point of the solar panels wouldn't be to fully charge the car but to assist the battery, especially while sitting in traffic or in between charges, while the car isn't plugged in. The sun gives away all that free energy. Might as well put the car to work to be more productive. read more