Northern States Power, a unit of Xcel Energy (NYSE: XEL), told the Wisconsin Public Service Commission on Jan. 22 that it should have new air emissions controls operating on the Bay Front coal plant by Feb. 28, 2015.
Under a December 2012 commission approval for this project, Northern States Power needs to file a quarterly progress report. Construction commenced on the project on May 30, 2013, with the start of pile installation. The project includes a baghouse installation and activated carbon injection.
Baghouse erection is complete. Enclosure of the baghouse and stair tower structures is about 90% complete. Erection of the five duct support towers is complete. “We identified that non-conforming bolts were used to assemble duct support towers two and three and portions of duct support tower one,” the company noted. “The contractor is replacing the subject bolts at their cost.”
The utility began installing the ductwork from the baghouse inlet plenums to the existing plant and materials for the ash collection system are on site and ready for installation in 2014.
As of Dec. 31, 2013, the overall percent of physical completion was approximately 55%. The company noted: “We anticipate placing the equipment in service on February 28, 2015. This is a change from the previous report mainly due to a change in the definition of ‘placed in service.’ While the equipment will be installed and operational by December 16, 2014 there will be a time period needed to start up the equipment, condition the fabric filter bags, and to implement a compliance stack test. We anticipate this work to be completed by February 28, 2015 at which time the baghouse and related equipment will be ‘placed in service.’”
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, 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 has 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.