CMP316: TNUoS Charging Methodology for Co-located Generation
What is being proposed
Charging arrangements for Generation sites which comprise multiple technology types within one Power Station (“co-located”)
Current status
The Panel met on 26 April 2019 and agreed that it goes to a Workgroup. Workgroup meetings commenced on 20 June 2019.This was de-prioritised by Panel whilst the Modifications to address Ofgem's Targeted Charging Review decision were being progressed. At June 2021 Panel, some Panel members noted that there has been greater interest in co-location over the previous 2-3 months and a Panel Member believed more sites will be re-purposed in the near future. Therefore, the June 2021 Panel agreed to change the priority from "Medium" to Medium to High". Workgroups re-commenced 27 September 2021 and Workgroup Consultation was issued 7 February 2022 and closed 5pm on 28 February 2022 with 8 non-confidential responses received. August 2022 Panel agreed that the Terms of Reference have been met and agreed for CMP316 to proceed to Code Administrator Consultation (but delay by a month so it can be run at this same time as the consequential Modification (CMP397). The consequential Modification (CMP397) was presented to September 2022 Panel and Panel agreed for this to proceed straight to Code Administrator Consultation. Code Administrator Consultation was issued at the same time as the CMP397 Code Administrator Consultation and was run from 4 October 2022 to 5pm on 1 November 2022 and 2 responses were received. Draft Final Modification Report was presented to November 2022 Panel for Panel recommendation vote. 3 Panel Members noted that changes to the legal text for CMP316 WACM1 are required as the legal text does not reflect the intent of CMP316 WACM1. Therefore Panel, under CUSC 8.23.4(iv), asked for the Workgroup to be re-formed (timing TBC) to update the legal text for CMP316 WACM1 and at the same time update the worked example (Annex 8) as to how CMP316 WACM1 works, which will help industry understanding. Panel will need confirmation that Workgroup have agreed the above and then a 2nd Code Administrator Consultation (full 15 Working Days given the extent of the Legal Text changes) will be issued specifically on the updates to CMP316 WACM1. Following conclusion of the 2nd Code Administrator, the Draft Final Modification Report will be re-presented to Panel for their recommendation vote. Given its interaction with CMP316, the CMP397 recommendation vote will also be delayed to when the CMP316 Draft Final Modification Report is re-presented to Panel. The March CUSC Panel 2024 agreed that the Workgroup had completed the required changes to the CMP316 WACM1 legal text and Annex 8 to progress to the Second Code Administrator Consultation was published to industry 25 March 2024 and will close at 5pm on 24 April 2024. The Second DFMR was submitted to the May CUSC Panel for Panel recommendation vote. At the May 2024 CUSC Panel, the Panel recommended by majority that WACM1 better facilitates the CUSC Applicable Objectives. The Final Modification Report was sent to Ofgem on 12 June 2024; CMP316 has an expected decision date of 24 January 2025 ( previously 29 November 2024). On the 13 December 2024 the Authority were unable to form an opinion and have sent back the FMR to Panel for a full review of the legal text for both the Original and WACM1 to be conducted. 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 and confirm the new timeline in the February Panel. On the Special CUSC Panel on the 14 February 2025, the Panel agreed that CMP316 should be placed as high priority in the Prioritisation Stack and be progressed alongside the current urgent modifications. The third Code Administrator Consultation will be presented to the June CUSC Panel to agree the send back Terms of Reference have been met. The CUSC Panel agreed on 27 June that following the send back decision, the CMP316 has met the Terms of Reference and can proceed to its Second Code Administrator Consultation which opened on 30 June and will close on 28 July. (11/08/2025) The Panel recommended unanimously that the Original and WACM1 better facilitated the Applicable CUSC Objectives. The Panel has recommended unanimously that the WACM1 is implemented. The Second Final Modification Report was submitted to the Authority on 08 August 2025.
Details
Timeline
Analysis
CMP316 establishes charging methodology for co-located generation sites combining multiple technologies at one power station. The modification has been through extensive industry review since 2019, with Panel unanimously recommending WACM1 for implementation in August 2025. The Second Final Modification Report was submitted to Ofgem on 8 August 2025.
Why it matters
This creates clearer charging arrangements for hybrid sites, reducing regulatory uncertainty for developers combining technologies like solar-plus-storage. As such, it supports the investment case for co-located projects by establishing predictable TNUoS charges, though the complex six-year development process reveals the difficulty of adapting charging frameworks to new generation models.
Key facts
- •Development began June 2019, took 6 years to resolve
- •Panel unanimously recommended WACM1 in August 2025
- •Second Final Modification Report submitted 8 August 2025
- •Medium impact on co-located generators