A solar roof; what a great idea. So between November and March, when it’s mostly cloudy and daylight is short, I guess I won’t be driving anywhere. Better stock up the larder for winter.
“Clouds decrease solar panel power output significantly, ranging from about 50 to 100% reduction in power depending on the heaviness of the clouds. Light cloud cover, but you can still see the sun. It will take about twice as long to charge your device than on a perfect day.”
https://www.voltaicsystems.com/blog/solar-performance-clouds-rain/
It’s all about gains in efficiency.