I hate to knock Elon Musk, but...

Tesla is a white elephant.

Look, the most efficient solar I ever heard of was solar dish engines.  These are about 30% efficient in turning sunlight into electricity.  So, I figured if you combine this with a car, you've got something.  But there's no way to do this.  You can't carry a solar engine on top of a car.

Perhaps you could hook up a battery to a solar dish engine at home.  Then swap batteries when you get home from work.  Or work at night and recharge in the day.

Otherwise, there's a problem directly connecting the two energy sources.  That's the only way that anyone can make it work.  Batteries are very efficient, in the ninety percent range.  Forcing utility companies to buy solar energy that you produce isn't.  Putting this electricity on the grid doesn't work because of its intermittent quality.  This forces the rest of rate payers to subsidize the energy, which still isn't cheap.  It would be cheap for cars, but for nothing else.

It doesn't pay to convert the solar energy into chemical energy for use later.  That's because the conversion is only 50% efficient at best.  You lose a lot that way.   Besides, going to chemical loses all the advantage of electrical operation.  Once you've gotten electrical energy, going back to chemical makes no sense at all.

Tesla is superficially plausible.  But the logic breaks down in the real world.  It doesn't work.