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Construction Program and Jointly-Owned Electric Generating Plants - Summary of Budgeted Construction Expenditures (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2017 USD ($) MW
Summary of Budgeted Construction Expenditures [Line Items] |
2018 | $ 500.2
2019 | 526.8
2020 | 500.4
2021 | 503.8
2022 | 680.9
Total | $ 2,712.1
Solar |
Summary of Budgeted Construction Expenditures [Line Items] |
Public utilities, number of megawatts | MW | 50
Public Service Company of New Mexico |
Summary of Budgeted Construction Expenditures [Line Items] |
2018 | $ 295.0
2019 | 339.0
2020 | 313.4
2021 | 315.8
2022 | 493.7
Total | 1,756.9
Anticipated expansion of transmission system | 170.0
Anticipated expansion of transmission system in 2021 | 100.0
Public Service Company of New Mexico | Solar |
Summary of Budgeted Construction Expenditures [Line Items] |
2018 | 72.8
Public Service Company of New Mexico | Four Corners Units 4 and 5 (Coal) |
Summary of Budgeted Construction Expenditures [Line Items] |
Expenditures related to environmental upgrades | 7.9
Public Service Company of New Mexico | San Juan Generating Station Units 1 and 4 |
Summary of Budgeted Construction Expenditures [Line Items] |
Potential shutdown of SJGS Units 1 and 4 in 2022 | 300.0
Texas-New Mexico Power Company |
Summary of Budgeted Construction Expenditures [Line Items] |
2018 | 185.8
2019 | 170.5
2020 | 170.0
2021 | 170.5
2022 | 170.1
Total | 866.9
Corporate and Other |
Summary of Budgeted Construction Expenditures [Line Items] |
2018 | 19.4
2019 | 17.3
2020 | 17.0
2021 | 17.5
2022 | 17.1
Total | $ 88.3

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