RALEIGH, NC — Progress Energy Carolinas will shutter four old coal-fired power plants lacking emissions control scrubbers by late 2017.

The four plants -- which include a total of 11 generating units -- produce nearly 1,500 megawatts (MW) of energy annually and will be supplanted by a combination of new natural gas and renewable energy generation.

"This is a significant commitment to clean air in our state and a major down-payment on our company's carbon-reduction strategy," CEO and President Bill Johnson said in a statement today. "Within seven years, we expect to retire nearly one-third of our coal fleet in North Carolina."

The company cited cost and increasing environmental regulations as the drivers behind the decision to close the units largely built in the 1950s. Progress Energy has already spent more than $2 billion implementing control systems at three plants in the state to reduce emissions of nitrogen oxides, sulfur dioxide, mercury and other pollutants.

In addition to avoiding these pollutants, the plant closures will reduce the amount of carbon dioxide emissions produced by Progress Energy at a time when Congress is debating a climate change bill and the world moves toward a global treaty that will succeed the Kyoto Protocol.

Regulatory and environmental concerns have increasingly put a crimp on plans for new coal power plants in recent years. Since 2001, more than 100 coal plants have been busted or abandoned, according to the Sierra Club.

Dynegy, for example, walked away from a joint venture earlier this year that would have built a fleet of coal-fired power plants in Arkansas, Georgia, Iowa, Michigan and Nevada. The Intermountain Power Agency in Utah also abandoned plans for expanding a coal power plant this summer when its largest customer -- the Los Angeles Department of Water and Power -- decided to phase out all coal-based electricity by 2020.

Meanwhile, a push for clean coal technology that would capture CO2 emissions from power plants and bury it deep in the ground has proceeded slowly, hindered by cost and uncertainty.

Coal was responsible for about 42 percent of global carbon dioxide emissions in 2006, according to the Energy Information Administration. In the U.S., more than half of electricity generation is coal-based. In late 2008, coal represented 35 percent of Progress Energy's generation mix.

The plant closures will impact 260 workers, which Progress Energy hopes to move to other positions within the company.

The four plants include a 600-MW site near Wilmington that will close in 2014; Progress Energy wants to build a natural gas plant to service the area and plans to seek regulatory approval within weeks.

A 316-MW plant near Moncure and a 172 MW plant near Lumberton will close between 2013 and 2017. The company may pursue renewable sources such as biomass to replace generation capacity, citing existing infrastructure and access to wood waste and other renewable sources.

Closure of its 397-MW Lee plant near Goldsboro (pictured above) was announced in August. The company wants to build a new $900 million 950-MW natural gas power plant scheduled to begin service in 2013.

Image courtesy of Progress Energy.