For me, the better solution for large-scale solar energy production are the solar collectors/concentrators, like the Stirling Energy System, http://www.youtube.com/watch?v=d_j_RxRR0lg

which are sturdier, more efficient than photovoltaic, don't require silicone and can be fabricated from standard glass, or even polished aluminum and steel, (which would make a great use for all those decommissioned airplanes busy rotting in the desert.)

Stirling's not the only company working on these things, but I like their style. Whether they're the best type is something that would require more tough questions.

Here's another approach:

http://www.solarpanelsdot.com/news/spain-builds-fist-solar-concentrator-tower-in-europe.html

And here's a good introductory article on the whole shebang

http://www.parc.com/research/publications/files/5706.pdf

The real chokepoint is in battery/storage/energy transportation tech, but I am quite sure that there will be a major commercial breakthrough very soon.