Capacity Remuneration Mechanism 2025/26 T-4 Capacity Auction Parameters decision paper

01 October 2021

The SEM Committee today, publishes the Parameters for the T-4 25/26 Capacity auction and SEMO today publishes the Initial Auction Information Pack (IAIP).

The IAIP contains key parameter decisions as detailed in our decision paper, plus additional decisions approved at our meeting in September 2021.

The CRM is central to meeting the security of supply challenge of the next few years. The procurement of new capacity four years ahead of the auction, allows for a diverse and dynamic portfolio of technology and fuel types, to meet the demands of domestic and business consumers of electricity.

This forthcoming T-4 25/26 auction seeks to qualify new projects across a range of technologies and fuel types, alongside the existing fleet, to compete for capacity contracts for delivery in the year Oct 2025 to Sept 2026.

The Capacity Requirement in the IAIP is as recommended by the TSOs based upon the GCS2020-29. It is worth noting that at the time of writing, a new GCS was published for 2021-2030.  Adjustments in this regard will be considered as part of the Final Auction Information Pack.

The Capacity Requirement represents an all-island requirement before system constraints are taken into account. For the Final Auction Information Pack, the Locational Capacity Constraint volumes are calculated, which reflect both the adjustments mentioned above, and the impact of constraints on the overall capacity requirement.