CMP477: Facilitating Cross TO Area Connection Modifications | National Energy System Operator
Summary
CMP477 proposes a CUSC change to allow a single connection modification request to span more than one Transmission Owner area, rather than forcing developers to raise separate applications when their works touch the boundary between TO networks. Raised by Andrew Urquhart on 19 May 2026 as an Urgent modification under an Authority-agreed timetable, status Proposal Raised. NESO classifies the impact as Medium across generators, demand customers, TOs (including CATOs) and consumers.
Why it matters
Reduces a transaction cost embedded in the CUSC's TO-by-TO geography: cross-boundary projects currently pay for the friction of running parallel modification processes, which lengthens connection timelines and entrenches incumbent TO boundaries. Winners are developers whose works straddle TO areas (including anyone connecting through a CATO into an existing TO network); losers are none in cost terms, though TOs lose some procedural control over their own patch.
Options on the table
CMP477 as proposed
Amend the CUSC to permit a single connection modification application to cover works across more than one TO area, replacing the current requirement for separate per-TO processes. Proceeds via the Urgent route under an Authority-agreed timetable, with the Authority taking the final decision.
Key facts
- •Modification reference CMP477 under the CUSC
- •Raised by Andrew Urquhart, 19 May 2026
- •Status: Proposal Raised
- •Governance route: Urgent modification on an Authority-agreed timetable with Authority decision
- •Impact assessed as Medium on generators, demand customers, NESO, TOs (including CATOs) and consumers
- •Enables a single connection modification request to cover more than one TO area
Areas affected
Related programmes
Memo
CMP477: Facilitating Cross TO Area Connection Modifications | National Energy System Operator Show/Hide Menu Toggle Add to favourites Close tooltip Sign in to add this page to your favourites Sign in or register Show favourites Close Close tooltip Sign in or register to manage your favourites Sign in or register Help You are now signed in Visit My NESO account to view and manage your dataset subscriptions. Maybe later Go to your account CMP477: Facilitating Cross TO Area Connection Modifications This modification enables cross‑Transmission Owner area connection change requests. Modification status: Current - Proposal Raised Last updated: 19 May 2026 Code Administrator Contact: [email protected] Proposed Governance Route: Urgent modification to proceed under a timetable agreed by the Authority (with an Authority decision) Medium impact: Generators and demand customers, NESO, Transmission Owners (including CATOs) and consumers. Code modification proposed by: Andrew Urquhart [email protected] Documents Proposal Form Terms Reference Workgroup Meetings and Summary Documents Workgroup Consultation Workgroup Report Code Administrator Consultation Decision Name CMP477 Proposal Form Draft / Final Modification Report logo--facebook