The provisional results of the latest T-4 capacity auction in Great Britain were published on Tuesday 22 February, with capacity contracts totalling 42.4GW allocated to electricity generators at an auction clearing price of £30.59/kW.
SSE can confirm that it has secured contracts for the 12 months from 1 October 2025 to 30 September 2026. This comprises 912MW of hydro-electric and pumped storage capacity and 2,643MW of gas-fired capacity, which includes its Peterhead (1,083MW), Marchwood (836MW) and Keadby 1 (723MW) power stations.
Additionally, the contracts include SSE’s first battery storage project in Salisbury, Wiltshire, which has received a 15-year agreement for 20MW of de-rated capacity.
SSE’s Medway Power Station, and its smaller embedded units at Burghfield and Chickerell, did not secure an agreement in this auction, however all have contracts in place until at least September 2023. The stations will also have opportunities to secure further capacity agreements in future auctions.
As electricity demand increases exponentially in the years ahead, flexible and reliable power will continue to be required to back up wind and solar generation, ensuring security of supply across the UK. In line with its commitment to a net zero future, SSE is actively progressing plans to deliver new low-carbon capacity to play this critical role, with cutting-edge carbon capture and storage (CCS) and pumped storage hydro projects in development.
"Our flexible hydro and thermal power stations continue to play a vital role in backing up renewable generation and ensuring security of supply, and we’re pleased to have provisionally secured these contracts for 2025/26. As we transition to net zero, we need to find ways to ensure this essential flexible generation capacity is low-carbon in its own right."
Martin Pibworth Group Energy and Commercial Director
Martin continued: “To help achieve that, we’ve recently submitted pioneering CCS projects at Keadby and Peterhead into the UK Government’s Cluster Sequencing Process, while we’re also looking to deliver the UK’s first large-scale pumped storage scheme in more than 30 years at Coire Glas.”
The provisional results are subject to confirmation by the Secretary of State for Business, Energy and Industrial Strategy (BEIS).
*A de-rating factor is applied to each station according to rules set by the UK Government.
**Seabank Power Station, in which SSE holds a 50% stake, also secured a contract in this auction for 1,144MW of de-rated capacity.