1. Energy Information Administration (http://www.eia.doe.gov/).
2. National Research Council (NRC), Trends in Oil Supply and Demand, the Potential for Peaking of Conventional Oil Production, and Possible Mitigation Options: A Summary Report of the Workshop, Washington, DC, 20 and 21 October 2005 (National Academies Press, Washington, DC, 2006).
3. Bush G. W. State of the Union address 20 January 2003.
4. Shinnar R. Citro F. “Solar thermal energy: The forgotten energy source ” presented at the American Institute of Chemical Engineers annual meeting Cincinnati OH 30 October to 4 November 2005 ( IEEE Technol. Soc. in press) (www1.ccny.cuny.edu/ci/cleanfuels/publications.cfm).
5. Supplemental calculations are available as supporting material on Science Online.