Columbia (WI)
Columbia Energy Center is a two-unit, 1,112 MW nameplate coal-fired steam plant in the Town of Pacific, Columbia County, Wisconsin, just south of Portage. Units 1 and 2 entered commercial service in May 1975 and May 1978 and remain in operation today. The plant is jointly owned by Alliant Energy's Wisconsin Power & Light Company, which is the majority owner and operator, along with WEC Energy Group's Wisconsin Public Service Corporation and MGE Energy's Madison Gas and Electric Company. After an original 2024/2025 closure target was pushed to mid-2026, the co-owners announced in December 2024 that they would keep burning coal at the plant through the end of 2029 while studying whether to convert at least one unit to natural gas. The plant sells its output into MISO, settling at the co-located ALTE.COLUMBAL1/2 and WPS.COLUMBIA1/2 nodes.