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Commitments and contingencies - Purchase Commitments (Details) $ in Thousands | Feb. 13, 2025 USD ($) MW | Jun. 30, 2025 USD ($)
--- | --- | ---
Jointly Owned Electricity Generation Plant | Badger Wind LLC |  |
Purchase commitments due |  |
Proportionate ownership share | 49.00% |
Net generating capacity | MW | 250 |
Payments to purchase ownership | $ 294,000 |
Wind generation ownership | MW | 122.5 |
Inventories |  |
Purchase commitments due |  |
2026 |  | $ 987,600
2027 |  | 269,400
2028 |  | 178,000
2029 |  | 138,200
2030 |  | 112,600
Thereafter |  | $ 654,800

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