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Sweden is testing a semi-truck trailer covered in 100 square meters of solar panels
(www.popsci.com)
This is a most excellent place for technology news and articles.
Thing is, we're no where close to running out of room. There's lots of land to use. I cannot speak for every country, but the US for sure has vast areas of nothing. A truck stop with a solar array nearby storing it for when the trucks stop buy to me makes way more sense to me at least.