So why didn't every Tesla owners charge up their car at night with the cheaper rate and sell the power back to the grid in the day time for a profit? 

Battery production is fine, there isn't enough demand for EVs yet. It is slowly ramping up with the pace of increasing demand. Yo can make all the EVs you want, but they will all be ended up sitting at the dealer lots if there is no demand, and right now, the demand for EV is still very low.

Infrastructure on the other hand is showing it's age and is lacking. That's where real progress can be made. With better infrastructure, then EVs will be a more attractive option for the general public, and driving up demand. 

 


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