What size solar panel do I need to produce 1342800 joules an hour?

The higher estimates are probably derived by taking the amount of water used (or consumed; there is a difference) in the USA and dividing by the population. The lower estimates are probably from home use only: drinking, washing, flushing toilets, and the like. Also, check the dates of the estimates.

A 1.6 gpf toilet uses a lot less water than a 5 or 7 gpf toilet did.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.