An analysis of the NREL shows that the United States technically could install 200,000 GW of solar power, generating somewhere around 400,000 TWh annually. This would supply the United States with 100 times more energy than its electricity generation capacity in 2010 (4,125 TWh).
Breaking that down along different methods of generating solar power, the report found that rooftop PV alone could generate 818 TWh of electricity each year, roughly 20% of current demand. Utility-scale PV in urban areas could generate 2,232 TWh, or 56% of demand.
A big potential lies in concentrating solar power, which has a potential of just over 116,000 TWh. However, the biggest potential is in utility-scale solar PV in rural areas, with 280,613 TWh of electricity technical capable of being generated each year.
The full report also goes into the potential of other renewable energy sources, but these far trail the technical potential of solar power.
Via PV Magazine