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COMMITMENTS AND CONTINGENCIES - Schedule of Estimated Future Annual Costs of Long term Contractual Agreement (Details) $ in Millions | Dec. 31, 2023 USD ($)
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Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | $ 1,315.8
2025 | 1,376.8
2026 | 1,228.8
2027 | 1,205.3
2028 | 1,169.7
Thereafter | 6,659.9
Total | 12,956.3
Renewable Energy Purchase Contracts |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 769.4
2025 | 863.0
2026 | 867.9
2027 | 897.6
2028 | 893.1
Thereafter | 5,368.8
Total | 9,659.8
Natural Gas Procurement |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 423.2
2025 | 402.3
2026 | 317.8
2027 | 264.8
2028 | 236.0
Thereafter | 1,211.8
Total | 2,855.9
Purchased Power and Capacity |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 86.7
2025 | 75.2
2026 | 2.9
2027 | 2.7
2028 | 2.7
Thereafter | 4.5
Total | 174.7
Peaker CfDs |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 17.2
2025 | 14.1
2026 | 12.8
2027 | 9.1
2028 | 6.8
Thereafter | 43.7
Total | 103.7
Transmission Support Commitments |
Transmission Support Commitments |
2024 | 19.3
2025 | 22.2
2026 | 27.4
2027 | 31.1
2028 | 31.1
Thereafter | 31.1
Total | 162.2
CL&P |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 727.4
2025 | 723.6
2026 | 651.7
2027 | 652.6
2028 | 651.3
Thereafter | 2,143.8
Total | 5,550.4
CL&P | Renewable Energy Purchase Contracts |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 618.8
2025 | 628.3
2026 | 628.0
2027 | 631.2
2028 | 632.2
Thereafter | 2,087.8
Total | 5,226.3
CL&P | Purchased Power and Capacity |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 83.8
2025 | 72.4
2026 | 0.1
2027 | 0.0
2028 | 0.0
Thereafter | 0.0
Total | 156.3
CL&P | Peaker CfDs |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 17.2
2025 | 14.1
2026 | 12.8
2027 | 9.1
2028 | 6.8
Thereafter | 43.7
Total | 103.7
CL&P | Transmission Support Commitments |
Transmission Support Commitments |
2024 | 7.6
2025 | 8.8
2026 | 10.8
2027 | 12.3
2028 | 12.3
Thereafter | 12.3
Total | 64.1
NSTAR Electric |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 133.5
2025 | 214.4
2026 | 220.1
2027 | 224.3
2028 | 220.1
Thereafter | 3,000.3
Total | 4,012.7
NSTAR Electric | Renewable Energy Purchase Contracts |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 123.0
2025 | 202.9
2026 | 206.5
2027 | 209.3
2028 | 205.1
Thereafter | 2,983.5
Total | 3,930.3
NSTAR Electric | Purchased Power and Capacity |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 2.9
2025 | 2.8
2026 | 2.8
2027 | 2.7
2028 | 2.7
Thereafter | 4.5
Total | 18.4
NSTAR Electric | Transmission Support Commitments |
Transmission Support Commitments |
2024 | 7.6
2025 | 8.7
2026 | 10.8
2027 | 12.3
2028 | 12.3
Thereafter | 12.3
Total | 64.0
PSNH |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 31.7
2025 | 36.5
2026 | 39.2
2027 | 63.6
2028 | 62.3
Thereafter | 304.0
Total | 537.3
PSNH | Renewable Energy Purchase Contracts |
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract] |
2024 | 27.6
2025 | 31.8
2026 | 33.4
2027 | 57.1
2028 | 55.8
Thereafter | 297.5
Total | 503.2
PSNH | Transmission Support Commitments |
Transmission Support Commitments |
2024 | 4.1
2025 | 4.7
2026 | 5.8
2027 | 6.5
2028 | 6.5
Thereafter | 6.5
Total | $ 34.1

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