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COMMITMENTS AND CONTINGENCIES - Schedule of Estimated Future Annual Costs of Long term Contractual Agreement (Details) $ in Millions | Dec. 31, 2024 USD ($)
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Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | $ 1,425.0
2026 | 1,400.7
2027 | 1,330.3
2028 | 1,273.0
2029 | 1,128.6
Thereafter | 7,403.8
Total | 13,961.4
Renewable Energy Purchase Contracts |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 771.8
2026 | 865.2
2027 | 919.9
2028 | 918.0
2029 | 785.5
Thereafter | 6,289.9
Total | 10,550.3
Natural Gas Procurement |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 532.6
2026 | 486.1
2027 | 364.6
2028 | 308.1
2029 | 294.9
Thereafter | 1,004.4
Total | 2,990.7
Capacity and Purchased Power |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 75.2
2026 | 2.9
2027 | 2.7
2028 | 2.7
2029 | 2.3
Thereafter | 2.3
Total | 88.1
Peaker CfDs |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 28.3
2026 | 27.7
2027 | 23.1
2028 | 23.3
2029 | 24.1
Thereafter | 84.6
Total | 211.1
Transmission Support Commitments |
Transmission Support Commitments |
2025 | 17.1
2026 | 18.8
2027 | 20.0
2028 | 20.9
2029 | 21.8
Thereafter | 22.6
Total | 121.2
CL&P |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 758.5
2026 | 707.1
2027 | 754.7
2028 | 756.1
2029 | 621.1
Thereafter | 3,567.1
Total | 7,164.6
CL&P | Renewable Energy Purchase Contracts |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 651.0
2026 | 671.9
2027 | 723.7
2028 | 724.5
2029 | 588.4
Thereafter | 3,473.6
Total | 6,833.1
CL&P | Capacity and Purchased Power |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 72.4
2026 | 0.1
2027 | 0.0
2028 | 0.0
2029 | 0.0
Thereafter | 0.0
Total | 72.5
CL&P | Peaker CfDs |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 28.3
2026 | 27.7
2027 | 23.1
2028 | 23.3
2029 | 24.1
Thereafter | 84.6
Total | 211.1
CL&P | Transmission Support Commitments |
Transmission Support Commitments |
2025 | 6.8
2026 | 7.4
2027 | 7.9
2028 | 8.3
2029 | 8.6
Thereafter | 8.9
Total | 47.9
NSTAR Electric |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 130.3
2026 | 203.5
2027 | 206.8
2028 | 204.4
2029 | 208.0
Thereafter | 2,827.5
Total | 3,780.5
NSTAR Electric | Renewable Energy Purchase Contracts |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 120.8
2026 | 193.3
2027 | 196.2
2028 | 193.5
2029 | 197.1
Thereafter | 2,816.3
Total | 3,717.2
NSTAR Electric | Capacity and Purchased Power |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2025 | 2.8
2026 | 2.8
2027 | 2.7
2028 | 2.7
2029 | 2.3
Thereafter | 2.3
Total | 15.6
NSTAR Electric | Transmission Support Commitments |
Transmission Support Commitments |
2025 | 6.7
2026 | 7.4
2027 | 7.9
2028 | 8.2
2029 | 8.6
Thereafter | 8.9
Total | 47.7
PSNH | Transmission Support Commitments |
Transmission Support Commitments |
2025 | 3.6
2026 | 4.0
2027 | 4.2
2028 | 4.4
2029 | 4.6
Thereafter | 4.8
Total | $ 25.6

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