Endnotes
Taking Climate Change into Account in U.S. Transportation
Endnotes
For a more complete discussion of this subject, see Reducing Greenhouse Gas Emissions From U.S. Transportation by David Greene and Andreas Schaefer, published by the Pew Center on Global Climate Change.
1 This assumes a blend of 90% gasoline and 10% ethanol by energy content. Ethanol derived from corn generates 30% less GHG emissions than the gasoline it replaces, when one considers the full fuel cycle. In the long term, ethanol may be derived from cellulosic feedstocks, resulting in approximately zero net GHG emissions over the full fuel cycle. (Greene & Schafer)
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2 Hybrid drive trains recover braking energy and shut off engines during idling time; they are already used in some Honda and Toyota vehicles.
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3 Driving resistance is the sum of forces opposing the motion of a vehicle, including inertia, aerodynamic drag and rolling resistance.
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4 U.S. Department of Energy (USDOE/OSTI), 2000. Technology Roadmap for the 21st Century Truck Program, 21CT-01, available at http://www.osti.gov/hvt/21stcenturytruck.pdf, Washington, DC.
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5 Greene and Schafer, 2003.
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6 Tennessee, Georgia, Arkansas, and New York are involved in the program.
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7 This comparison assumes gasoline engines with high air-fuel ratios producing the same power.
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8 Statistics on highway user revenues and their disposition are from the U.S. Department of Transportation, Federal Highway Administration, Highway Statistics, table HF-10.Revenue and expenditure estimates for non-highway modes are from the U.S. Department of Transportation, Bureau of Transportation Statistics, Pocket Guide to Transportation 2003, tables 26 and 27, available at www.bts.gov.
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9 National Recycling Coalition and Buy Recycled Business Alliance.
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10 See www.travelmatters.org Combatting Global Warming through Sustainable Surface Transportation Policy, prepared for the Transit Cooperative Research Program, Transportation Research Board, National Research Council, by the Center for Neighborhood Technology, Chicago, IL
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References
Greene, David L. and Andreas Schafer, 2003. Reducing Greenhouse Gas Emissions from U.S. Transportation. Pew Center on Global Climate Change, Arlington, VA.
Shapouri, H., J.A. Duffield and M. Wang, 2002. The Energy Balance of Corn Ethanol: An Update, Agricultural Economic Report No. 813, U.S. Department of Agriculture, Office of the Chief Economist, Office of Energy Policy and New Uses, Washington, D.C.
Wang, M.S., 2002. GREET Web Site, http://greet.anl.gov/, Argonne National Laboratory, Argonne, IL.
Wang, M.Q., 1999. GREET 1.5 - Transportation Fuel Cycle Model, Volume 1: Methodology, Development, Use and Results, ANL/ESD-39, vol. 1, Argonne National Laboratory, Argonne, IL