The current U.S. electricity demand is roughly 4 trillion watts (4 Terawatts or TW) and is growing at approximately 2.5% per year. Current projections place demand somewhere between 11 TW and 18 TW by 2050.
Coal has afforded a wealthy rise in living standards - for the lucky countries - but now the rest of the world want the same and energy consumption is expected to more than triple towards the end of this century.
I can smell the coffee. None of our current technologies could come close to providing a practical or satisfactory solution capable of dealing with tripling the power... which really only gives us one choice and that is to do the impossible.