U.S. Department of Energy - Energy Efficiency and Renewable Energy

Tribal Energy Program

Solar Energy Resources

Unlike wind and hydropower, the solar energy resource varies by less than a factor of 2 from the sunniest to the cloudiest parts of the country. The solar energy resource is also relatively well characterized throughout the United States. A wealth of solar resource information, including maps and 8760-hour data sets, can be found at the following Web sites from the National Renewable Energy Laboratory: