New SCR at WPL’s Edgewater Unit 5 just about completed

Wisconsin Power and Light, a unit of Alliant Energy (NYSE: LNT), told the Public Service Commission of Wisconsin that the $153.9m selective catalytic reduction installation on Edgewater Unit 5 is nearly complete and that the SCR should be operational in December.

In May 2010, the PSCW issued an order approving the application for this SCR to control NOx on Unit 5 at Edgewater in Sheboygan County, Wisc. As of the Oct. 17 update filed at the commission the project is forecasted to be completed within the estimated cost, the utility noted.

Construction on the project commenced in August 2010. As of the Oct. 17 update, engineering progress is 99% complete and construction progress is 86.3% complete. The forecasted in-service date for the SCR is December.

Also, WPL has picked dry flue gas desulfurization, with Powder River Basin coal as the design fuel, for installation at Edgewater Unit 5 to comply with various clean-air mandates. WPL provided details about the project in a July 27 request for authorization from the PSCW. The application covers a DFGD system and a fabric filter (FF) for control and removal of SO2 on Edgewater Unit 5.

Edgewater Unit 5 is one of WPL‘s larger and most efficient units. It consists of a wall-fired boiler with a gross maximum operating load of 430 MW. It is equipped with low NOx burners (LNB) and separated overfire air (SOFA) to reduce NOx emissions. Edgewater Unit 5 is also equipped with a cold-side electrostatic precipitator (ESP) for particulate control and activated carbon injection (ACI) to reduce mercury emissions. The nearly-completed SCR is designed to further reduce NOx emissions to meet Phase II Reasonably Available Control Technology (RACT) requirements.

“Edgewater Unit 5 will benefit from the installation of the Control System through SO2 emissions reductions of at least 90%, which also reduces the formation of fine particulate matter (PM2.5) in the atmosphere, as SO2 is a precursor to PM2.5 formation,” the application for DFGD noted. “Reductions in SO2 emissions of at least 90% translate into the removal of over 220,000 tons of SO2 from Edgewater Unit 5‘s current emissions over a 30 year period. Installation of a FF is a necessary component of a DFGD system to control particulate matter (PM) emissions. The installation of the FF will provide additional benefit by reducing hazardous air pollutants emitted from Edgewater Unit 5.”

The DFGD project is estimated to cost $413.7m. WPL‘s modeling of the project against the outright retirement of Edgewater Unit 5 demonstrates that the project is the most cost-effective alternative for meeting future capacity and energy needs of WPL‘s customers, the utility said.

Edgewater is located in the city of Sheboygan, Wisc., along Lake Michigan. Edgewater Unit 5 began operating in 1985 with a design gross capacity of 380 MW. The unit currently runs at a gross maximum operating load of 430 MW and burns low-sulfur PRB coal. Unit 5 has a Babcock & Wilcox wall-fired boiler.

About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.