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Is the roof of a Tesla a solar panel?
Why not? If you park your car for day or two, when you come back it should have more of a charge than when you left it. My $20.00 yard lights have them...
Is there a solar panel on the back of your phone?
Why not?
If you set your phone down on your desk for a while, when you pick it up again it should have more of a charge than when you left it. My $2.00 calculator has one...
Bigger question, why has no one brought this up already? They seem like obvious questions to me.
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More efficient to have them on your house so the car doesn't have the extra weight.