TRANSPORTATION ENERGY DATA BOOK: EDITION 20 - Center for ...

Table 4.5
Emissions of Nitrogen Oxides from Highway Vehicles, 1970-98”
(million short tons)
Percent of
Source category 1970 1975 1980 1985 1990 1992 1993 1994 1995 1996 1997 1998 total, 1998
Gasoline powered
Light vehicles & motorcycles 4.16 4.73 4.42 3.81 3.22 3.61 3.68 3.57 3.44 2.98 2.93 2.85 36.7%
Light trucksb 1.28 1.46 1.41 1.53 1.26 1.36 1.42 1.66 1.52 1.95 1.96 1.95 24.7%
Heavy vehicles 0.28 0.32 0.30 0.33 0.33 0.31 0.32 0.35 0.33 0.33 0.33 0.32 4.2%
Total 5.71 6.51 6.13 5.67 4.80 5.28 5.42 5.58 5.30 5.26 5.22 5.09 65.5%
Diesel powered
Light vehicles c 0.02 0.03 0.03 0.04 0.04 0.04 0.04 0.04 0.04 0.03 0.03 0.4%
Light trucksb c c 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.2%
Heavy vehicles 1.68 2.12 2.46 2.39 2.24 2.30 2.34 2.45 2.48 2.54 2.61 2.63 33.9%
Total 1.68 2.14 2.49 2.42 2.29 2.35 2.39 2.49 2.53 2.59 2.66 2.68 34.5%
Total
Highway vehicle total 7.39 8.65 8.62 8.09 7.09 7.62 7.81 8.08 7.83 7.85 7.87 7.77 100.0%
Percent diesel
22.7% 24.8% 28.9% 30.0% 32.3% 30.8% 30.6% 30.9% 32.3% 33.0% 33.7% 34.5%
Source:
U. S. Environmental Protection Agency, National Air Pollutant Emission Trends, 1900-1998, 2000, p. A-9 and annual.
(Additional resources: www.epa.govloarloaqps)
“The sums of subcategories may not equal total due to rounding.
bLess than 8,500 pounds.
‘Data are not available.