If you were to set aside $50bn for R&D, you'd be able to make a molten salt powerplant and you'd be able to sell thousands of them, but the problem is no one wants to put up the money because as soon as you do it, the next guy is going to copy you and he's going to spend his $50bn on bribing politicians to get his design licensed and yours won't be.

Bitcoin mining MIGHT change this situation.