NREL. 2004b. PV Solar Radiation: Annual. Washington, D.C. Available at http://www.nrel.gov/gis/images/map_pv_us_annual_may2004.jpg.
NREL. 2006. Geothermal—The Energy Under Our Feet. Geothermal Resource Estimates for the United States. Washington, D.C.
NREL. 2007. Very Large Scale Deployment of Grid Connected Solar PV in the United States. Washington, D.C.
Roy, B.S., S.W. Pacala, and R.L. Walko. 2004. Can large wind farms affect local meteorology? Journal of Geophysical Research 109:D19101.
USDA/DOE (U.S. Department of Agriculture/Department of Energy). 2005. Biomass as Feedstock for a Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion-Ton Annual Supply. Washington, D.C.
USGS (U.S. Geological Survey). 1979. Assessment of Geothermal Resources of the United States—1978. Geological Survey Circular 790. Arlington, Va.
WGA (Western Governors’ Association). 2006a. Clean and Diversified Energy Initiative: Geothermal Task Force Report. Washington, D.C.
WGA. 2006b. Clean and Diversified Energy Initiative: Solar Task Force Report. Washington, D.C.