It's not exactly a "Peak Silicon" yet, but it's definitely a problem for the development of alternative energy/solar energy.
About 25% of the earth's crust is Silicon. That's something you're not going to run out of any time soon... Maybe you're speaking about something related to how chips are made? The starting material is sand...
The trick is that the silicon needs to be very, very pure. Similarly to uranium, and platinum. And Columbite-tantalite (which also kills gorillas). And so forth.
There's a decreasing stock of pure silicon, and Silicon Valley is running "dry". No one has uttered the words yet for Peak Silicon, but it is just a matter of time. In the meantime, it's whipping up prices.
Some links here:
Silicon: http://www.findarticles.com/p/articles/mi_zdext/is_200504/ai_n13602425
Columbite-tantalite killing gorillas: http://www.cellular-news.com/coltan/
Computer chips have a high environmental impact relative to their weight. For every gram of a microchip, 630 grams of fossil fuels are used, whereas for every gram of an automobile, only 2 grams of fossil fuels are used. This is due to the fact that making very pure, organized and hence low entropy structures from high entropy materials require large energy inputs. Automobiles, while made with heavy materials, do not require the level of purity and sophistication of materials as a microchip. The energy used in producing nine or ten computers is enough to produce an automobile.
Here is an account of various purification procedures
At last, an energy accounting for silicon solar panels
it appears that the popular Siemens mfrg method is actually less energy efficient than some newer method called UCC (and what I know about this industrial inorganic chem stuff you could write on a standard-size matchbook cover)...
just a snack for y'all... The difference between theory and practise in practise ...
