Environmental Engineering Reference
In-Depth Information
Table 8.7
Carbon dioxide emission factors for electricity generation in the United States,
1999-2002.
Region
Carbon dioxide
(tonne/MWh)
1
New York, Connecticut, Rhode Island, Massachusetts, Vermont,
New Hampshire, and Maine
0.466
2
New Jersey, Delaware, Pennsylvania, Maryland, West Virginia,
Ohio, Indiana, and Michigan
0.782
3
Illinois and Wisconsin
0.638
4
Missouri, Kentucky, Virginia, Arkansas, Tennessee, North Carolina,
South Carolina, Louisiana, Mississippi, Alabama, and Georgia
0.690
5
Florida
0.678
6
Texas
0.730
7
Oklahoma and Kansas
0.867
8
North Dakota, South Dakota, Nebraska, Minnesota, and Iowa
0.875
9
Colorado, Utah, Nevada, Wyoming, and Montana
0.909
10
New Mexico and Arizona
0.658
11
Oregon, Washington, and Idaho
0.147
12
California
0.350
13
Hawaii
0.858
14
Alaska
0.749
15
U.S. Territories
0.858
U.S. Average
0.676
Adapted from EIA-1605, 2007.
somehow more complicated because it will depend on the how the energy is produced. Utility
companies use a combination of coal, nuclear, hydro, natural gas, geothermal, wind, and other
sources to produce electricity; therefore, the emission factors for electricity will depend on the
utility company. In the United States, the Department of Energy has divided the country in
15 regions for the purpose of estimating emission factors (Table 8.7). And Table 8.8 presents
average emission factors for other selected countries. A full list for the rest of the world is
available in the Department of Energy's publication EIA-1605.
Example of calculation of emissions
The following example is about a hypothetical brewing company located in the foothills of the
Ozark Mountains in Arkansas. Magnitudes are not representative of the industry except emis-
sion factors that were obtained from the EPA (see Tables 8.6 and 8.7). In the reference year,
2007, used for this inventory, the brewery produced 50 million liters of beer, purchased
60 × 10
6
kWh (60 MWh) of electricity and 6 × 10
4
GJ of natural gas. The company owns 5
large diesel trucks and 15 small gas passenger vehicles for administrative use. The large trucks
are used for transporting the beer to five distribution centers that will be included within the
organizational boundaries of the company and therefore considered as direct emissions. In
addition, the company outsources the distribution of beer from the distribution center to the
final sale points. For this purpose, the outsourced company owns 30 mid-size diesel trucks and
the emissions from these small trucks will be considered as indirect and reported under
Scope III. The 5 large trucks are driven about 5 × 10
5
miles per year and use 71,418 gallons of
diesel per year; the mid-size contracted trucks drive 1 × 10
6
miles (1.6 × 10
6
km) per year and
the amount of diesel burned is unknown; and the small vehicles approximately drive 2.25 × 10
5
miles per year totaling a consumption of 10,714 gallons of gasoline.
