This is part of the same solar woo that produced Solar Freaking Roadways.Solar works when it faces the sun, when it's away from traffic and dust sources, and when it isn't partially shaded.Cars and building facades have none of those features. If you want to make double use of space for solar, first build a thing that doesn't need sunlight, then build a roof over it and put panels on those.Space efficiency is not what we need to improve with solar panels, it's cost efficiency. Fortunately for us, the levelized cost of power from solar is competitve and still improving.
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