>And without checking, my ballpark guess would be that you get at least 10 times more solar energy out of a panel in Texas than a panel in, say, Canada. Our eyes are just so good at adapting to different light levels that we don't notice the different energy densities that much.

Should have checked. "Canada" is pretty vague, but if you mean the southern part where people live you're waaay off. It's only a factor of 2.

http://solargis.com/assets/graphic/free-map/GHI/Solargis-Wor...