Survey of Energy Resources 2007
Solar Country Notes
United States of America
Raw solar resources are far in excess of all projected energy demand in the mid-term. Solar insolation levels in the US vary from less than 400 W/m2 to over 700 W/m2, depending on latitude, climate (primarily average cloud cover), terrain, and application (that is, using a fixed-angle collector compared to a collector that tracks the sun). However, the USA has approximately 9 million square kilometres of land area.
The United States Energy Association (the WEC Member Committee for the USA) reports that, according to the EIA, central station photovoltaic capacity was 11 000 kW at the end of 2005 and that, on the basis of the stock of equipment in place, there was an estimated 485 000 kW of dispersed PV capacity in operation. Output of electricity from the centralised PV capacity was 15 593 MWh, implying an average capacity factor of approximately 0.16.
Solar thermo-electric capacity at end-2005 is reported as 400.4 MW, producing 534 701 MWh during the year, at a capacity factor of 0.15.
Direct solar heating panels produced a total of 51 652 TJ in 2005.
The aim of the Department of Energy's Solar Energy Technologies Program (Solar Program) is, through public-private partnerships, to 'bring reliable and affordable solar energy technologies to the marketplace'. The Solar Program currently carries out research and development in the fields of PV and CSP systems for electricity generation, and into solar heating systems for producing hot water (or hot air) for domestic, commercial or industrial purposes. The Program is also investigating a form of solar lighting that uses small solar concentrators and fibre optics in combination to provide daylight illumination inside buildings.