1. These categories were first developed in The Potential of Renewable Energy: An Interlaboratory White Paper, by Idaho National Engineering Laboratory et al., prepared for the Department of Energy, March 1990.
2. Silverman, Murray and Susan Worthman, The Future of Renewable Energy Industries, The Electricity Journal, March 1995.
3. Kirshner, D., Barkovich, B., Trevelen, K. and Walther, R., “A Cost-Effective Renewables Policy Can Advance the Transition to Competition”, The Electricity Journal, January/February 1997.
4. Scenarios of U.S. Carbon Reductions: Potential Impacts of Energy-Efficient and Low-Carbon Technologies by 2010 and Beyond, by the Interlaboratory Working Group on Energy-Efficient and Low-Carbon Technologies (ORNL, NREL, PNNL, LBNL, and ANL), prepared for the U.S. Department of Energy (DOE), August 1997.
5. Energy Information Administration, U.S. Department of Energy, Federal Energy Subsidies: Direct and Indirect Interventions in Energy Markets, SR/EMEU/92-02, 1992.