2028/29 T-4 Auction, Volumes Information Note

2028/29 T-4 Auction, Volumes Information Note

The SEM Committee is today publishing an information note on the decisions it made in determining the volumes to be procured for the 2028/29 T-4 Capacity Remuneration Mechanism (CRM) auction.


Whilst the TSOs calculate the initial Capacity Requirement in accordance with the Capacity Requirement and De-Rating Factor Methodology, they also submit a number of adjustments for the SEM Committee’s consideration. The note details these adjustments and the view taken by the SEM Committee on these proposals.


The 2028/29 T-4 auction was held in December 2024 and resulted in the procurement of around 606MWd of New Capacity. Of this 132WMd was new ‘other storage’ (i.e. battery storage) capacity, which is a record volume of battery storage in any auction to date. In addition, this was the first auction held since the introduction of a new policy on Intermediate Length Contracts and substantial investment was secured in refurbishing 1,646MWd of existing capacity.


The information note also reflects on the impact of the CRM to date, highlighting that as of April 2025, a total of just over 1,000 MWd of the multi-year new capacity contracted for 2028/29 has already achieved completion.