Provisional capacity auction results
The provisional results of the latest T-1 capacity auction in Great Britain were published on Wednesday 5 March, with a total of 7,936MW in capacity agreements awarded to capacity market units at an auction clearing price of £20/kW.
SSE Thermal's capacity auction results
SSE Thermal has provisionally secured agreements for 756MW of de-rated* electricity generation capacity for the 2025/26 delivery year, which runs from 1 October 2025 to 30 September 2026. This includes its Medway Power Station on the Isle of Grain (668MW) and its smaller embedded plants at Burghfield (44MW) and Chickerell (44MW).
SSE Thermal’s other GB generating units have existing agreements for this delivery year, and all assets including those that participated in this T-1 auction have future agreements until at least September 2028.
SSE Renewables's capacity auction results
In addition, SSE Renewables secured provisional agreements for around 63MW of de-rated capacity which included two units at its joint venture Seagreen Offshore Wind Farm for the same 2025/26 delivery year. SSE will have a 49% share of earnings based on its equity stake in the asset^.
The provisional results are subject to confirmation by the Secretary of State for Energy Security and Net Zero (DESNZ).
*A de-rating factor is applied to all capacity according to rules set by the UK Government.
^Seagreen Offshore Wind Farm is a joint venture between SSE Renewables (49%), TotalEnergies (25.5%) and PTTEP (25.5%).