CMP417: Extending principles of CUSC Section 15 to all Users
What is being proposed
This modification looks to extend the principles of CUSC Section 15 “User Commitment Methodology” to Users on Final Sums methodology, resulting in all Users being on the User Commitment Methodology. This will introduce equitable treatment across User groups and reduce barriers to entry as a User’s security amount will better reflect the transmission liabilities they impose should they cancel connection or reduce capacity
Current status
Proposal issued to the July 2023 CUSC Panel. The July 2023 CUSC Panel unanimously agreed that CMP417 should follow the Standard Governance Route and proceed to Workgroup. The Panel agreed the Terms of Reference for the Workgroup. Workgroup Nominations opened on 01 August 2023 and closed 29 August 2023. The first Workgroup was scheduled for 06 September 2023. Updated Terms of Reference were approved by the September 2023 CUSC Panel. Due to the Proposer changed their solution and a STC modification also required to progress this modification, a revised timeline was approved at the November 2023 CUSC Panel Ahead of the CUSC Panel approving the reconvening of Workgroup meetings,the Proposer and Connections SME will complete additional detailed worked examples and verification through a subgroup. October 2024 CUSC Panel prioritised as Medium, therefore Workgroup activity will start from Spring 2025. Upon receipt of the Authority Open Letter on 31 January: Outlining their approach to prioritisation of electricity transmission network charging modifications, Panel will review the modification status in the February Panel.On 14 February 2025 at the Special CUSC Panel the Panel discussed, at length and in detail, the prioritisation of CUSC Modifications. The CUSC Panel agreed there is no change to this priority status. (28/03/2025) On 28 March 2025 CUSC Panel discussed at length and in detail the prioritisation of CUSC Modifications. The CUSC Panel agreed this modification be placed as high on the prioritsation stack. Workgroups are in progress. (21/01/2026) On 19 January CMP417 Workgroup Consultation opened and closed on 09 February.
Details
Timeline
Analysis
CMP417 proposes extending the User Commitment Methodology to all grid connection users, replacing the Final Sums methodology for transmission-connected demand, distribution-connected demand, and DNOs. This would standardise security requirements across user groups, with security amounts reflecting actual transmission liabilities rather than fixed sums. The modification affects high-impact parties including NESO, TOs, DNOs, and demand users currently on Final Sums.
Why it matters
This removes barriers to entry by making security deposits proportional to actual transmission costs imposed, rather than requiring potentially excessive fixed sums from smaller users. The reform favours new entrants and distributed generators by creating equitable treatment, though it shifts cost allocation risk from socialised fixed charges to individual liability-based security.
Key facts
- •Workgroup consultation opened 19 January 2026, closed 9 February 2026
- •Affects transmission-connected demand, distribution-connected demand, and DNOs not triggered by embedded generators
- •Requires cross-code changes to STC and STCP
- •Panel prioritised as high priority March 2025