The U.S. solar market increased by 67 percent in 2010 — from $3.6 billion in 2009 to $6 billion — making it the nation’s fastest-growing energy sector, according to a trade industry report. Total installed capacity of photovoltaic and solar thermal systems reached 956 
megawatts — more than twice the 442 megawatts of added capacity in 2009 — to reach a cumulative installed capacity of 2.6 gigawatts, according to the Solar Energy Industries Association report. That is enough to power more than 500,000 homes. The report said that solar power capacity is likely to double again in 2011 as a result of federal tax incentives, increased demand, and falling prices for solar technology. Sixteen states each installed more than 10 megawatts of photovoltaic capacity, compared with four in 2007. However, the U.S.’s global share in installed PV systems dropped from 6.5 percent to 5 percent as a result of strong industry growth in Germany and Italy.
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