Ofgem rejects CMP330/374 on self-built grid links and consults on a wider route
Victoria Shinder1 min readOfgem published on 7 October its decision to reject CUSC modification CMP330/374, a proposal first raised in December 2019 to let parties connecting to the British transmission network build more of their own connection assets.
What the proposal wanted. Today, users may, with the transmission owner's agreement, self-build and transfer connection assets that are 2 km or less in length. Energie Kontor's CMP330 would have made cable and overhead-line lengths over 2 km contestable. Its CMP374 went further: any length of connection asset, except where shared. The CUSC Panel merged the two in May 2021, and in July 2023 unanimously recommended approval.
Why it was rejected. The new contestability framework was meant to sit in a separate modification, CMP414, and the two were to be implemented together. Ofgem sent CMP414 back in July 2024 because the evidence was insufficient to judge a net benefit, and NESO withdrew CMP414 on 29 June 2026. Without it, CMP330/374 could only delete the existing provisions.
What replaces it. Ofgem says many of the benefits the proposer described — quicker and cheaper delivery, more competition — match its own aims, but that wider changes are needed, including licence changes to protect consumers, which the code modification process cannot deliver. Alongside the decision it published a consultation on expanding self-build and transfer, using powers under the Planning and Infrastructure Act and covering demand, generation and storage connections.
For developers, the practical meaning is a delay rather than a defeat: the 2 km limit stays for now, and the route to longer self-built connections moves from industry code to regulation.