Entrepreneurs have realized this, but energy is far more difficult than people will admit. Even if this works and is cheap, the real issue is batteries. Batteries are expensive and their manufacture entails environmental costs. There is no free ride. Yes, Tesla wants to reduce the price of batteries, but that doesn't make it so.

If this works you need many multiples of battery capacity as production. That is a staggering amount of batteries. And batteries don't have a long life. How is the battery life on a 10 year old computer?