Not a dumb question at all.
Solar panels wouldn't even be a rounding error in the amount of power these vehicles store in the battery. Eventually there will be magnetic contactless charging strips in highways like modern toothbrush / cell phone chargers.
This is a good summary of what the current approach people use for charging. Pre-Covid, I drive 125 miles a day;
Interesting article that I agree with. Reminds me of the early days of cell phone charging or laptop; Now, people only seek long deep charges at most daily; Not the hourly slurps in the early days;
Most EV Charging Infrastructure Is Wasted Due To Lack Of New Thinking
https://www.forbes.com/sites/bradtem.../#7647fdf1195e
Most charging is done in people's homes. The other three places charging works are:
At hotels (or other places you stay the night.)
At workplaces where people park all day, especially for those who can't charge at home
High speed charging for special long trips