From an article by D.J. Slater in the Marshfield News Herald:

New emission control equipment at the Weston Power Plant has reduced the amount of nitrogen oxide produced at its two oldest generators by 53 percent.

The equipment improves the coal burning process at the plants, decreasing nitrogen emissions. The $7.5 million worth of equipment went on line in March.

“This is part of our company’s overall nitrogen oxide emission reduction control plan … for our older coal-fueled generating units,” said Bruce Bruzina, the assistant vice president of energy supply operations for the plant, in a news release.

Nitrogen oxide is a group of highly reactive gases that contain nitrogen and oxygen. It’s one of the primary ingredients in smog and acid rain, and contributes to global warming and causes respiratory problems, according to the U.S. Environmental Protection Agency.

The upgrades are part of Wisconsin Public Service Corp.’s effort to meet more stringent state and federal air quality requirements that the EPA established in 2005, said David Capozella, a WPSC representative. The Weston Power Plant had to meet those new standards by 2010, he said.

Wisconsin Public Service Corp., which owns the Weston Power Plant, plans to start installing nitrogen oxide reduction equipment on a third generator in September, with a completion date sometime in mid-2010, he said.