I take issue with "of course". It will be always be wildly more economic to produce solar power in places with a lot of sun. 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...
That's the problem with not checking and using your intuition. The difference between Florida and Toronto is only x2. Not x10.
And it can actually be less efficient if there's too much sun, solar panel efficiency decreases with temperature. Solar thermal also depends on temperature differential, so if the environment around the plant is too hot the efficiency drops.