Regulatory Other

On 23 October 2025, Ofgem published its Final Decision on Connection and Use of System Code (CUSC) modification proposal CMP444 — "Introducing a cap and floor to wider generation TNUoS charges" — rejecting the original proposal and all alternative variants. CMP444 had been raised in response to NESO's 10-year forecast showing Transmission Network Use of System (TNUoS) charges potentially tripling for generators in TNUoS Zone 27 (north of Scotland) and other northern zones. The proposal would have applied an upper and lower limit (cap and floor) to wider generation TNUoS tariffs to reduce investment uncertainty for developers in remote-from-demand locations. Ofgem concluded that neither the original solution nor the alternatives would better facilitate the applicable charging objectives compared to the baseline, and committed to publish a timeline for delivering full TNUoS reform by 2029 under the Review of Electricity Market Arrangements (REMA) Reformed National Pricing workstream. This decision is materially significant for the 2 GW West of Orkney Windfarm: the project sits in Zone 27, where TNUoS charges have already tripled since the September 2023 forecast and add up to ~30% to project costs versus comparable sites in southern England. The CMP444 rejection removed the most proximate near-term mechanism for restoring competitive parity for ScotWind projects in CfD allocation rounds, and was cited by the developer (Corio Generation, TotalEnergies and RIDG) as one of the key drivers — alongside the project's absence from the AR7 awards (14 January 2026) — for the 21 January 2026 announcement that further investment in West of Orkney would be paused until TNUoS reform delivers a viable route to market.