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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.
I love your optimism, bit that's not how any of this works.
It will never be more efficient to put panels on the vehicle. Any vehicle ever. Dirt, trees, buildings, bridges, tunnels, etc. All block light. And panels available today, are around 23% efficiency. And they only get worse over time, estimated a 90% lots at 20 years.
Could they make better panels someday, sure. Would it still make more sense to put those panels on top of buildings or an open areas where they can get lots of sun. Yes.