Why Aircraft CO
is of Concern
- Travel by plane can be quite energy efficient. The US Environmental Protection Agency estimates that energy consumption in the US commercial airline fleet was about 53 miles per gallon per passenger seat in 2003. This number has increased from about 28 miles per gallon per passenger seat mile in 1970 due to increases in aircraft load factor and increases in the efficiency of aircraft engines. However, it is not expected that that such dramatic improvements will continue in the future as limits are being reached in both load factor and engine efficiency.
- While the efficiency of air travel via a highly loaded airliner compares favorably to that of other common transit modes, such as automobiles, the same cannot be said for smaller sized airplanes carrying less than a full load of passengers. For example, a typical executive jet, carrying a single passenger might have an efficiency of only about 3 miles per gallon per passenger.
- Precisely because air travel is so convenient and fast, it is easy for an individual to “produce” a lot of CO2 by taking a common trip. For example, a single round trip via commercial airliner from Seattle to New York would produce as much CO2 as a typical home produces in three months. The same trip in an executive jet would produce the same amount of CO2 as a typical home produces in 3.7 years.
- CO2 emissions from aircraft are receiving increasing attention simply due to the rapid worldwide growth in air travel. It has been estimated that CO2 emissions from aircraft will exceed that of automobiles by 2020.