[_ph_]

If you have the solar cells with your car, you don't need to charge the whole battery in one hour. You have to recharge during one day what you are using in your daily driving. Which is of course much less. In Germany a car drives less than 50 kilometers per day on average, so that is less than 10 kWh per day.

[giobox]

12 hours of sun, the best you can hope for any time soon is about 3kwh put back into the car. In other words, a few miles of range can be restored.

There is a reason no car manufacturer is currently seriously pursuing solar roofs - it's just too small a surface area to generate meaningful energy in a car context. The math doesn't work.

We might see systems (as we've seen in past) where solar helps power accessories on the 12v system (AC/in car entertainment etc), but its not going to meaningfully affect range of the vehicle or help top up the traction battery.

[ben_w]

> 12 hours of sun, the best you can hope for any time soon is about 3kwh put back into the car. In other words, a few miles of range can be restored.

Horizontal solar radiation is 3 kWh/m^2/day, in Germany. 5 m^2 of PV on the car in the article I linked to. 0.25-ish wH/mile is roughly what Teslas get. That works out as 60 miles times the cell efficiency per day, call it 12-24 miles in practice with 20-40% efficient cells. Matches the article pretty well, considering how far north Germany is.

> no car manufacturer is currently seriously pursuing solar roofs

I literally linked to a car manufacturer doing just that :P

[giobox]

> I literally linked to a car manufacturer doing just that :P

You literally linked to a car tech startup whose unproven prototype technology has shipped in exactly zero production cars, yes ;) There is no car manufacturer doing this meaningfully today, and again likely won't be soon.