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Joint Plant Ownership | 12 Months Ended
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Dec. 31, 2015
Regulated Operations [Abstract] |
Joint Plant Ownership | Joint Plant Ownership - MGE Energy and MGE. a. Columbia. MGE and two other utilities jointly own Columbia, a coal-fired generating facility located in Portage, Wisconsin, which accounts for 31% (242 MW) of MGE's net summer rated capacity. Power from this facility is shared in proportion to each company's ownership interest. MGE has a 22% ownership interest in Columbia. The other owners a re WPL, which operates Columbia, and WPSC. MGE's share of fuel, operating, and maintenanc e expenses for Columbia was $38.2 m illion, $28.1 million, and $37.5 million for the years ended December 31, 2015, 2014, and 2013, res pectively. Each owner provides its own financing and reflects its respective portion of facilities and operating costs in its financial statements. MGE's interest in Columbia, included in its gross utility plant in service, and the related accumulated dep reciation reserves at December 31 were as follows:
| (In thousands) |  | 2015 |  | 2014 |
| Utility plant | $ | 273,762 | $ | 268,597 |
| Accumulated depreciation |  | (84,864) |  | (80,645) |
| Property, plant, and equipment, net |  | 188,898 |  | 187,952 |
| Construction work in progress |  | 17,110 |  | 6,941 |
| Total property, plant, and equipment | $ | 206,008 | $ | 194,893 |
b. Elm Road. MGE Power Elm Road owns an 8.33% ownership interest in each of two 615 MW coal-fired generating units in Oak Creek, Wisconsin, which accounts for 14% (106 MW) of MGE's net summer rated capacity. Unit 1 entered commercial operation on February 2, 2010. Unit 2 entered commercial operation on January 12, 2011. MGE Power Elm Road's sole principal asset is that ownership interest in those generating units. MGE P ower Elm Road's interest in the Elm Road Units is leased to MGE pursuant to long-term leases. The remainder of the ownership interest in the Elm Road Units is held by two other entities, one of which is also responsible for the Units' operation. Each own er provides its own financing and reflects its respective portion of the facility and costs in its financial statements. MGE's share of fuel, operating, and maintenance expenses for the Elm Road Units was $20.9 million, $20.3 million, and $13.4 million for the years ended December 31, 2015, 2014, and 2013, respectively. MGE Power Elm Road's interest in the portion of the Elm Road Units in-service and the related accumulated depreci ation reserves at December 31 were as follows:
| (In thousands) |  | 2015 |  | 2014 |
| Nonregulated plant | $ | 202,326 | $ | 199,582 |
| Accumulated depreciation |  | (24,422) |  | (19,962) |
| Property, plant, and equipment, net |  | 177,904 |  | 179,620 |
| Construction work in progress |  | 2,400 |  | 1,976 |
| Total property, plant, and equipment | $ | 180,304 | $ | 181,596 |
c. WCCF. MGE Power West Campus and the UW jointly own the West Campus Cogeneration Facility located on the UW campus in Madison, Wisconsin. MGE Power West Campus owns 55% of the facility and the UW owns 45% of the facility. The UW owns a controlling interest in the chilled-water and steam plants, which are used to meet the growing needs for air-conditioning and steam-heat capacity for the UW campus. MGE Power West Campus owns a controlling interest in the elect ric generation plant, which is leased and operated by MGE. Each owner provides its own financing and reflects its respective portion of the facility and operating costs in its financial statements. MGE Power West Campus' interest in WCCF and the related a ccumulated depreciation reserves at December 31 were as follows:
| (In thousands) |  | 2015 |  | 2014 |
| Nonregulated plant | $ | 111,141 | $ | 111,453 |
| Accumulated depreciation |  | (26,738) |  | (24,691) |
| Property, plant, and equipment, net | $ | 84,403 | $ | 86,762 |
Operating charges are allocated to the UW based on formulas contained in the operating agreement. Under the provisions of this arrangement, the UW is required to reimburse MGE for their allocated portion of fuel and operating expenses. For the years ended December 31, 2015, 2014, and 2013, the UW allocated share of fu el and operating costs was $3.7 million, $2.8 million, and $4.9 million, respectively.

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- Definition Describes that the entity has a proportionate interest in a jointly owned utility plant. Should include a table showing separately for each interest the amount of plant in service, the accumulated provision for depreciation (if available), the amount of plant under construction, and the proportionate share. The amounts presented may be further subdivided to show amounts applicable to plant subcategories (for example, production, transmission, distribution). Should include statements that the amounts represent the utility's share in each joint plant and that it must provide its own financing. Information concerning two or more generating plants on the same site may be combined. Should state that the utility's share of direct expenses of the joint plants is included in the corresponding operating expenses on its income statement (for example, fuel, maintenance of plant, other operating expense). If the share of direct expenses is charged to purchased power then should disclose the amount so charged and the proportionate amounts charged to specific operating expenses on the records maintained for the joint plants. + References No definition available. + Details
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- References No definition available. + Details
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