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Jointly-Owned Facilities and Projects | 12 Months Ended
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Dec. 31, 2018
Jointly-Owned Facilities and Projects [Abstract] |
Jointly-Owned Facilities and Projects [Text Block] | JOINTLY-OWNED FACILITIES AND ASSETS Boswell Unit 4. Minnesota Power owns 80 percent of the 585 MW Boswell Unit 4. While Minnesota Power operates the plant, certain decisions about the operations of Boswell Unit 4 are subject to the oversight of a committee on which it and WPPI Energy, the owner of the remaining 20 percent, have equal representation and voting rights. Each owner must provide its own financing and is obligated to its ownership share of operating costs. Minnesota Power’s share of operating expenses for Boswell Unit 4 is included in Operating Expenses on the Consolidated Statement of Income. CapX2020. Minnesota Power was a participant in the CapX2020 initiative which represented an effort to ensure electric transmission and distribution reliability in Minnesota and the surrounding region for the future. CapX2020, which consisted of electric cooperatives and municipal and investor-owned utilities, including Minnesota’s largest transmission owners, assessed the transmission system and projected growth in customer demand for electricity through 2020. Minnesota Power participated in certain CapX2020 projects which were completed and placed in service by 2015. Minnesota Power’s investments in jointly-owned facilities and projects and the related ownership percentages are as follows:
Regulated Utility Plant | Plant in Service | Accumulated Depreciation | Construction Work in Progress | % Ownership
Millions |  |  |  |
As of December 31, 2018 |  |  |  |
Boswell Unit 4 |  | $650.1 |  |  | $229.9 |  |  | $6.4 |  | 80
CapX2020 | 101.0 |  | 11.0 |  | — |  | 9.3 - 14.7
Total |  | $751.1 |  |  | $240.9 |  |  | $6.4 |  |
As of December 31, 2017 |  |  |  |
Boswell Unit 4 |  | $668.2 |  |  | $222.8 |  |  | $8.2 |  | 80
CapX2020 | 101.0 |  | 8.4 |  | — |  | 9.3 - 14.7
Total |  | $769.2 |  |  | $231.2 |  |  | $8.2 |  |

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- Definition Jointly-Owned Electric Facility [Text Block] + References No definition available. + Details
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- Definition Jointly-Owned Facilities and Projects [Abstract] + References No definition available. + Details
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