It adds cost and complexity to the cars, so that's one reason not to do it. Still - I have an EV that's sitting idle most of the time because of the pandemic.

It adds cost and complexity to the cars, so that's one reason not to do it. Still - I have an EV that's sitting idle most of the time because of the pandemic. I had to plug it in a handful of times this year, that would mean plugging it in zero times. Also, if it is very sunny, it means the car is hot. One common thing to do is to start climate control before getting into the car so it will be at a comfortable temperature. We would get this heat rejection for free? Is it worth it? Not sure. Maybe. Everything else being the same (including price) I would pick a car equipped like this versus another car without this feature. By the way, some Nissan Leaf trims had a small solar panel to charge the 12v battery. That was useful. Mine has to periodically connect the traction battery to do the same.