» Oak Ridge Data on Fuel Efficiency

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Edition 26, the latest edition of the Transportation Energy Data Book, was posted on May 29 on Oak Ridge National Laboratory’s website.  ORNL publishes this under contract to the U.S. Department of Energy.  The new edition contains data for both 2004 and 2005.

It shows that, in 2005, domestic airlines on average consumed 20.5% more energy per passenger-mile than Amtrak, while cars consumed 27.2% more than Amtrak.  Looked at the other way round, Amtrak consumes 17.0% and 21.4% less energy per passenger-mile than airlines and cars, respectively.  [One passenger-mile is one passenger traveling one mile.]

Those percentages are derived from these Oak Ridge figures (British Thermal Units or BTUs per passenger-mile, 2005 data), organized here most to least efficient:

Amtrak: 2,709
Commuter rail: 2,743
Rail transit: 2,784
Certificated air carriers: 3,264 (excludes international services)
Cars: 3,445

As nationwide average figures, these figures do not reflect:

• Externalities, which generally are positive for rail and negative for air. Rail tends to support pedestrian- and transit-friendly development;
• The fact that short air flights are far more energy intensive than longer flights; and
• The greater damage that aircraft emissions do because they occur at such high altitudes.  (Financial Times reported on May 18, “because the gases [from flying] are emitted at a high altitude, they are estimated to have at least twice as much warming effect on the climate than if they were at ground level.")

• Oak Ridge now recognizes one kilowatt-hour as equivalent to 10,339 BTUs (rather than the 11,765 used in previous years) and revised previous-year data to reflect this, so all passenger rail modes are shown as more efficient than in Edition 25);
• Oak Ridge assumes 138,700 BTUs per gallon of diesel fuel, apparently a “timeless” figure as it was also used in a December 1977 report by Ram K. Mittal, Energy Intensity of Intercity Passenger Rail, prepared for U.S. DOT, Research and Special Programs Director, Office of University Research.
• In 2005, Amtrak for the first time since 1995 was more energy efficient than both commuter rail and rail transit.
• Amtrak consumed 14.6 trillion BTUs in 2005, which was 8.2% less than 15.9 trillion in 2003 and 19.3% below Amtrak’s peak year of energy use (2001, with 18.1 trillion BTUs).
• Amtrak in 2005 consumed 65,477,000 gallons of diesel fuel and used 531,377,000 kilowatt hours. [Both figures exclude consumption by commuter railroads for which Amtrak provides services.]
• This indicates that 62.3% of Amtrak energy is diesel fuel vs. 37.7% electricity.

[Note: Table 2.12 has 2004 data because 2005 data is not yet available for some modes. As the relevant footnotes explain, the airline statistics in Table 2.12 include “1/2 of international scheduled services” whereas those in Table 2.14 do not include any international services. This report also has considerable freight data.]

The “What’s New” page for Edition 26 reports that, “The transportation share of U.S. energy use reached 28.4% in 2006 which is the highest share recorded since 1970.” The page also reflects a disturbing trend towards less information:

• “Due to more stringent data restrictions imposed by R.L. Polk, the latest number of vehicles by age that we are allowed to publish is 2001.” (Tables 3.5 & 3.6)
• The American Metals Market discontinued the survey which collected information on the average materials in a domestic car; therefore, the 2003 data are the latest available. (Table 4.14)
• The Census Bureau has discontinued the Vehicle Inventory and Use Survey; the 2002 data are therefore the latest data available. (Tables 5.4–5.9)
• The Department of Transportation has discontinued the National Household Travel Survey; therefore, the 2001 data are the latest data available. (Tables 8.5–8.13 & 8.17)
• The EPA has not published new data from the National Emissions Inventory since the 2002 data; thus, Tables 12.1–12.11 remain unchanged.

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