WASHINGTON - The most detailed data yet on emissions of heat-trapping gases show that U.S. power plants, including plants in Montana and Wyoming, are responsible for the bulk of the pollution blamed for global warming.
Power plants released 72 percent of the greenhouse gases reported to the Environmental Protection Agency for 2010, according to information released Wednesday that was the first catalog of global warming pollution by facility. The data include more than 6,700 of the largest industrial sources of greenhouse gases, or about 80 percent of total U.S. emissions.
According to an Associated Press analysis of the data, 20 mostly coal-fired power plants in 15 states are the top emitters of the greenhouse gases.
The analysis showed that PPL Montana's Colstrip plant in Colstrip was No. 8 with 17.1 million metric tons of greenhouse gases. The Jim Bridger plant at Point of Rocks, east of Rock Springs, Wyo., was 14th among the top 20 plants. The Jim Bridger plant reported 14.8 million metric tons of emissions.
Gina McCarthy, the top air official at the EPA, said the database marked "a major milestone" in the agency's work to address climate change. She said it would help industry, states and the federal government identify ways to reduce greenhouse gases.
The Obama administration plans to regulate emissions of heat-trapping gases under existing law. A proposed regulation to address pollution from new power plants could be released as early as this month. Eventually, the EPA will have to tackle facilities already in operation. The largest emitters will be the first in line.
The largest greenhouse gas polluter in the nation in 2010, according to the EPA's data, was the Scherer power plant in Juliette, Ga., owned by Southern Co. That coal-fired power plant reported releasing nearly 23 million metric tons of carbon dioxide, the chief greenhouse gas, in 2010.
Two other power plants owned by Southern were the second- and third-largest polluters nationally: the Bowen plant in Cartersville, Ga., and the James H. Miller Jr. power plant in Quinton, Ala. The plants are some of the largest coal-fired power plants in the country.
American Electric Power, another large coal-fired power producer, has three power plants in the top 20. They are in Rockport, Ind.; Cheshire, Ohio; and St. Albans, W.Va.
Dave Hoffman, a PPL Montana spokesman, said the company is reviewing the information but noted that EPA was looking at stationary sources, not mobile sources, such as vehicles.
PPL is not surprised the Colstrip plant is included among the larger power plant producers of the gas. The Colstrip plant, Hoffman said, is the biggest coal-fired plant in Montana and the second-biggest coal plant west of the Mississippi River.
"We've done a lot of major investments over the last 10 years with a variety of emissions," Hoffman said.
The four-unit plant in Rosebud County can produce up to 2,094 megawatts of power, burns low-sulfur Montana coal and employs about 360 people, the company said.
The EPA information showed that the Colstrip plant was, by far, the largest of Montana's 36 industrial sources of greenhouse gases. In second place was PPL Montana's J.E. Corette coal-fired plant in Billings. The Corette plant's 2010 emissions were 1.05 million metric tons.
The Hardin Generating Station, in Big Horn County, was third with 909,511 metric tons.
In Wyoming, the Jim Bridger plant operated by PacifiCorp Energy can produce 2.1 million kilowatts per hour in four units. The EPA listed 105 industrial greenhouse gas emitters in Wyoming.
"This is just another way to identify the largest coal-fired power plants in the country," said American Electric Power spokesman Pat Hemlepp. "We always assumed we would be No. 1 in greenhouse gas emissions or No. 2 behind Southern Co. AEP and Southern are the two largest consumers of coal."
Both companies are testing technology to capture carbon dioxide from power plants and pump it underground for storage. But to date, no one has proven that capture is possible for a commercial-sized power plant.
The other states with high-polluting power plants are Texas, Michigan, Missouri, Pennsylvania, Arizona, North Carolina, Kansas and Kentucky.
Refineries were the second-largest source of greenhouse gas emissions, with 5.7 percent of the reported total. The top states in greenhouse gas emissions from power plants and from refineries were Texas, Pennsylvania, Florida, Ohio, and Indiana.
Congress required industries to report their greenhouse gas emissions as part of a 2008 spending bill. Until now, the agency has estimated greenhouse gas emissions by industry sector.
"The information is sure to make companies, localities and specific plants more conscious of their emissions profile and may lead some to lower emissions themselves," said Paul Bledsoe, senior adviser at the Bipartisan Policy Center, a Washington think tank that works on energy and environmental issues.
Billings Gazette reporter Clair Johnson contributed to this story.