
Northern States Power, a unit of Xcel Energy (NYSE: XEL), told the Public Service Commission of Wisconsin on Oct. 24 that the new baghouse and activated carbon injection systems for its coal-fired Bay Front plant are due for operation in December 2014.
In December 2012, the commission approved this project, with a proviso that the company file quarterly updates on construction progress.
Construction commenced on May 30 with the start of pile installation. Foundation construction is complete. NSP said it executed a contract for the supply of ductwork support structural steel, the supply of ductwork and the erection of the Siemens-supplied baghouse, ductwork support structural steel and ductwork up to the existing plant.
The utility said it has received the permits necessary to begin erecting structures on the foundations and mobilized the erection contractor to the site. It received six of the eight baghouse modules, baghouse inlet and outlet plenums, carbon silo and other miscellaneous components.
As of Sept. 30, the overall percent of physical completion was about 10%. The anticipated in service date is Dec. 16, 2014.
The Wisconsin commission on Dec. 5, 2012, approved this $18.5m retrofit project for Bay Front boilers 1 and 2. The Bay Front plant is located on the shore of Chequamegon Bay, Lake Superior. Currently, three boilers feed steam into a combined steam header system that can support three turbine-generator sets. These boilers, known as boilers number 1, 2, and 5, currently burn fuels including coal, waste wood, railroad ties, tire-derived fuel, and natural gas to produce steam that drive the three turbine-generator sets (identified as numbers 4, 5, and 6) to produce electricity.
Of the three existing turbine-generator sets, #4 has a capacity of 22 MW and came into service in 1949, #5 has a capacity of 22 MW and came into service in 1952, and #6 has a capacity of 30 MW and was placed in service in 1957.
NSP is constructing new baghouse and ACI facilities to reduce particulate matter and mercury emissions from boilers #1 and #2 at the facility. NSP said it has no plans to install additional air control equipment on boiler number 5 because it intends to burn only natural gas in that boiler after Jan. 1, 2015, in order to comply with the Wisconsin mercury reduction rule.