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COMMITMENTS AND CONTINGENCIES - Schedule of Estimated Future Annual Costs of Long term Contractual Agreement (Details) $ in Millions | Dec. 31, 2021 USD ($)
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Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | $ 1,251.4
2023 | 1,168.1
2024 | 1,113.6
2025 | 1,118.4
2026 | 1,020.1
Thereafter | 5,184.3
Total | 10,855.9
Renewable Energy |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 755.4
2023 | 700.7
2024 | 696.4
2025 | 718.7
2026 | 714.3
Thereafter | 3,571.4
Total | 7,156.9
Natural Gas Procurement |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 377.9
2023 | 323.6
2024 | 270.5
2025 | 265.5
2026 | 250.4
Thereafter | 1,517.2
Total | 3,005.1
Purchased Power and Capacity |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 76.0
2023 | 87.1
2024 | 86.7
2025 | 75.1
2026 | 2.9
Thereafter | 9.8
Total | 337.6
Peaker CfDs |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 26.1
2023 | 38.9
2024 | 39.4
2025 | 36.7
2026 | 29.9
Thereafter | 63.3
Total | 234.3
Transmission Support Commitments |
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract] |
2022 | 16.0
2023 | 17.8
2024 | 20.6
2025 | 22.4
2026 | 22.6
Thereafter | 22.6
Total | 122.0
The Connecticut Light and Power Company |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 690.7
2023 | 721.4
2024 | 723.3
2025 | 711.7
2026 | 630.8
Thereafter | 2,824.4
Total | 6,302.3
The Connecticut Light and Power Company | Renewable Energy |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 586.2
2023 | 592.1
2024 | 592.0
2025 | 593.9
2026 | 591.9
Thereafter | 2,752.2
Total | 5,708.3
The Connecticut Light and Power Company | Purchased Power and Capacity |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 72.1
2023 | 83.4
2024 | 83.8
2025 | 72.3
2026 | 0.1
Thereafter | 0.0
Total | 311.7
The Connecticut Light and Power Company | Peaker CfDs |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 26.1
2023 | 38.9
2024 | 39.4
2025 | 36.7
2026 | 29.9
Thereafter | 63.3
Total | 234.3
The Connecticut Light and Power Company | Transmission Support Commitments |
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract] |
2022 | 6.3
2023 | 7.0
2024 | 8.1
2025 | 8.8
2026 | 8.9
Thereafter | 8.9
Total | 48.0
NSTAR Electric Company |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 112.2
2023 | 88.2
2024 | 86.7
2025 | 87.8
2026 | 88.1
Thereafter | 511.0
Total | 974.0
NSTAR Electric Company | Renewable Energy |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 102.9
2023 | 78.3
2024 | 75.7
2025 | 76.1
2026 | 76.4
Thereafter | 492.3
Total | 901.7
NSTAR Electric Company | Purchased Power and Capacity |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 3.0
2023 | 2.9
2024 | 2.9
2025 | 2.8
2026 | 2.8
Thereafter | 9.8
Total | 24.2
NSTAR Electric Company | Transmission Support Commitments |
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract] |
2022 | 6.3
2023 | 7.0
2024 | 8.1
2025 | 8.9
2026 | 8.9
Thereafter | 8.9
Total | 48.1
Public Service Company of New Hampshire |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 70.6
2023 | 34.9
2024 | 33.1
2025 | 53.4
2026 | 50.8
Thereafter | 331.7
Total | 574.5
Public Service Company of New Hampshire | Renewable Energy |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 66.3
2023 | 30.3
2024 | 28.7
2025 | 48.7
2026 | 46.0
Thereafter | 326.9
Total | 546.9
Public Service Company of New Hampshire | Purchased Power and Capacity |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2022 | 0.9
2023 | 0.8
2024 | 0.0
2025 | 0.0
2026 | 0.0
Thereafter | 0.0
Total | 1.7
Public Service Company of New Hampshire | Transmission Support Commitments |
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract] |
2022 | 3.4
2023 | 3.8
2024 | 4.4
2025 | 4.7
2026 | 4.8
Thereafter | 4.8
Total | $ 25.9

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