"up to" is doing A LOT of heavy lifting.

There is a mountain of difference in solar power that can be collected on June 21 vs December 21. We all know that, there are many more hours in the day. but what many people don't know is that even limited to the same productive hours, let's say 9a-4p, summer light has a lot more power.

Because it's their own marketing, you can count on "Up to 20 miles per day" meaning 20 miles (in an extremely efficient EV), in the ideal circumstances, on the best day of the year. The rest of the year will be worse, probably much worse.

But don't take my word for it, and certainly don't take theirs. Wait for independent reviews, and check them. See what people can actually expect from such a system. As much as I would love for this to be a real solution for most people, it's very unlikely.