Correspondence

Full details of auction parameters and interconnector de-rating factors

Published 15 July 2025

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Table 1: Auction parameters听听

T-1 Auction for delivery in 2026/27 T-4 Auction for delivery in 2029/30
Auction target capacity 5.8 GW 39.1 GW
Demand curve: minimum capacity at price cap 4.8 GW 37.6 GW
Demand curve: maximum capacity at 拢0 6.8 GW 40.6 GW
Reliability Standard 3 hours LOLE 3 hours LOLE
Net CONE 拢49/kW/yr 拢49/kW/yr
Price Cap 拢75/kW/yr 拢75/kW/yr
Price Taker Threshold 拢25/kW/yr 拢25/kW/yr
15-year agreement threshold N/A[footnote 1] 拢350/kW[footnote 2]
9-year agreement threshold (for eligible Declared Low Carbon CMUs only) N/A[footnote 1] 拢205/kW[footnote 3]
3-year agreement threshold (for non-Three Year Zero Capex Threshold CMUs) N/A[footnote 1] 拢65/kW[footnote 4]
3-year agreement zero threshold (for eligible Three Year Zero Capex Threshold CMUs only)[footnote 5] N/A[footnote 1] 拢0/kW
Indexation N/A[footnote 1] 2024/25

Table 2: Interconnector de-rating factors (DRF)

T-1 auction鈥痜or听the 2026/27听delivery year[footnote 6] T-1 auction鈥痜or听the 2026/27听delivery year[footnote 6] T-4 auction鈥痜or听the 2029/30 delivery year T-4 auction鈥痜or听the 2029/30 delivery year
Interconnector Connection capacity (GW) NESO range (%) DRF (%) NESO range (%) DRF (%)
滨贵础鈥�(贵谤补苍肠别) 2 - - 54-92 62
滨贵础2鈥�(贵谤补苍肠别) 1.1 - - 54-92 64
贰濒别肠尝颈苍办鈥�(贵谤补苍肠别) 1 - - 54-92 68
叠谤颈迟狈别诲鈥�(狈别迟丑别谤濒补苍诲蝉) 1.2 - - 46-90 67
Moyle鈥�(Northern Ireland) 0.5 - - 7-85 60
EWIC鈥�(Republic of Ireland) 0.5 - - 7-85 60
Greenlink (Republic of Ireland) 0.5 - - 7-85 60
狈别尘辞尝颈苍办鈥�(叠别濒驳颈耻尘) 1 - - 54-92 68
狈厂尝鈥�(狈辞谤飞补测) 1.4 - - 51-89 70
痴颈办颈苍驳尝颈苍办鈥�(顿别苍尘补谤办) 1.4 - - 32-86 63
Neuconnect (Germany) 1.4 - - 40-88 63

  1. Multi-year agreements are not awarded in the T-1 auction.听鈫�听鈫�2听鈫�3听鈫�4听鈫�5

  2. The 15-year agreement threshold is adjusted from the previous T-4 value (for the 2028/29 Delivery Year) for inflation, indexed to the 2024/25 inflation level, and rounded to the nearest 拢5.听鈫�

  3. The 9-year agreement threshold has been introduced for the upcoming auctions, as described in the Phase 2 response update. The threshold is set as the midpoint between the 3-year (for non-Three Year Zero Capex Threshold CMUs) and 15-year agreement thresholds, rounded to the nearest 拢5.听鈫�

  4. The 3-year agreement threshold (for non-Three Year Zero Capex Threshold CMUs)听was decreased to 拢65/kW to facilitate lifetime extensions as described in this consultation response.听鈫�

  5. As defined in Rule 1.2 of the Capacity Market Rules, as described in the Phase 2 response update.听鈫�

  6. For the T-1 auction, all interconnectors expected to be operational for 2026/27 already hold capacity agreements for the 2026/27 delivery year.听鈫�听鈫�2

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