The Prius used to have an option for a solar panel roof before (the article mentions this) - and all the tiny panel was used for was to run the cabin fan to kee

The Prius used to have an option for a solar panel roof before (the article mentions this) - and all the tiny panel was used for was to run the cabin fan to keep the cabin a bit cooler if you ended up parking in the sun. The difference with the cells in the article is they are 0.03mm thick so they don't weigh as much and can be curved around more car body parts.