Mr. Fork, with all due apologies, there is actually extensive recylcing & reclamation of solar cells. The Si-cells, which are the most common commercial solar cells, are 99.999% pure Si, and, as you mentioned, take a fair amount of energy to produce (more on this later). Solar cells typically take 10-20 years for any noticable drop in performance, and, even then, the drop is slight. Typical drops in yearly performance is dust/debis on the panels, which can be removed easily enough. If/when a panel needs replacing, those panels are used as raw materials for new panels (why waste the purity?). New technologies have also significantly reduced the energy required from 75-125 kWh / kg Si all the way down to 10 - 30 kWh / kg Si. These new technologies also eliminate the need for silanes, which are both toxic and dangerous. Improvements in effiencies & technology have also reduced the thickness of panels from 300 microns down to 180 microns, resulting in substantially less Si needed for the same power generated.
The more exotic (and more efficient) solar panels are CdTe, CuInSe2, and GaAs. These panels are incredibly thin, on the order of 1 - 3 microns, and encased to glass to protect it. If & when a panel needs to be replaced, there are extensive procedures already in place to leach & precipitate out the above elements resulting in a mineral-rich filter cake and clean glass, which are both used in the generation of new panels.
One of the major factors to keep photovoltaics competitive is sustainability, thus there are very aggressive recylcing efforts and new technologies to minimize the environmental impact.
The cost of generating power via photovoltaics has dropped significantly...even below $1.00 per watt generated, making it very competitive.
Yes, I am studing photovoltaics at the graduate level, and my office at work is next door to the photovoltaics division.
