13.6 Energy Sources, Generation, Consumption 395
■Figure 13.15
U.S electric power industry net
generation (2007).
Source: EIA, Form EIA-923,
“Power Plant Operations
Report” and predecessor form(s)
including Form EIA-906,
“Power Plant Report” and Form
EIA-920, “Combined Heat and
Power Plant Report”.Natural gas
21.6%Total = 4,157 billion kilowatthours
Nuclear
19.4%Coal
48.5%Other gases
0.3%Other
0.3%Petroleum
1.6%Other
renewables
2.5%Hydroelectric
5.8%Coal
In 2007, the U.S. electric power industry generated nearly 4, 157 billion kilowatthours. Coal,
natural gas, petroleum, nuclear, and renewable sources were used to generate electricity. From
examining Figure 13.15, you can see that almost half (48.5%) of all electricity generated in
the United States was created from coal. Coal-fired power plants burn coal in boilers or steam
generators to make steam. The steam then turns turbines that are connected to generators to
create electricity. Figure 13.16 shows the major regions where coal is mined in the United
States. According to the U.S. Department of Energy, nearly 93% of the coal mined in the
U.S. is used for generating electricity. The rest of the coal is used in other industries including
steel, cement, and paper, to process materials.Natural Gas
The U.S. natural gas transportation network consists of 1.5 million miles of mainline and
secondary pipelines. These pipelines connect production areas and markets, and in 2008
delivered more than 23 trillion cubic feet of natural gas to about 70 million customers
(Figure 13.17). Salt caverns, depleted oil reservoirs, or aquifer reservoirs serve as under-
ground storage facilities to store natural gas as a seasonal backup supply. Aboveground liq-
uefied natural gas storage facilities are also used to store natural gas. In 2007, there were
approximately 400 active storage fields. The major gas transportation pipelines in U.S. are
shown in Figure 13.17, and the percentage of natural gas transmission pipeline mileage in
each state is shown in Figure 13.18.Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s).圀圀圀⸀夀䄀娀䐀䄀一倀刀䔀匀匀⸀䌀伀䴀圀圀圀⸀夀䄀娀䐀䄀一倀刀䔀匀匀⸀䌀伀䴀