If the US government wanted to make solar powered homes and electric cars kings they could. But they would do so at the expense of gas, coal and electric utility providers, auto makers and oil companies. Guess how much those industries combined spend on lobbying efforts?
If one day I finally put up a website to sell the powercube I would probably disappear the following week never to be heard from again.

Didn't that happen to the guy that said he had an engine that ran on water?