New Regulatory Instructions and Guidance (RIGs) for Sizewell C (nuclear licensee): consultation

Publication type:: Consultation
Status:: Closed (with decision)
Publication date:: 23 July 2025
Last updated:: 15 September 2025
Closed date:: 20 August 2025
Topic:: Low carbon and nuclear energy
Subtopic:: Nuclear Regulated Asset Base (RAB) model
Industry sector:: Generation and Wholesale Market

Show all updates

Share the page

Details of Outcome

We are issuing the Regulatory Instructions and Guidance (RIGs) for Sizewell C following a 28-day Consultation period from 23 July to 20 August 2025. During the consultation we did not receive any substantive comments and there have been limited changes to the documents we consulted on. The RIGs are being published under Special Conditions 21.11 and 21.12 of the Regulated Asset Base licence for Sizewell C. The RIGs will take effect on the licence modification date for Sizewell C as determined by Department for Energy Security and Net Zero.

Read the full outcome

Sizewell C (nuclear licensee): regulatory instructions and guidance (RIGs)

Original consultation

The Authority proposes to issue new Regulatory Instructions and Guidance (RIGs) under Special Conditions 21.11 and 21.12 of the Regulated Asset Base licence for Sizewell C.

Details

These RIGs contain:

instructions and guidance on how to report and, where applicable, derive information, including a list of definitions (Overview of the RIGs)
instructions and guidance on how to complete the RFPR template including a list of definitions (RFPR Guidance)
reporting packs, specifically the Revenue Workbook, Cost and Schedule Workbook and the Regulatory Financial Performance Reporting (RFPR) template for the submission of numerical information

The documents listed above are now available for review. These RIGs are the primary means by which the Authority obtains information from the nuclear licensee on compliance with licence conditions. Representations must be submitted by 20 August 2025, following a 28-day consultation period beginning on 23 July 2025. The Final RIGs will take effect on the licence modification date for Sizewell C as determined by Department for Energy Security and Net Zero.

Get more information

Learn more about our role: Nuclear Regulated Asset Base (RAB) model.

Note: the Sizewell C (nuclear licensee): Cost and Schedule Workbook attached below is not fully accessible. If you require an alternative format, please contact RABmodel@ofgem.gov.uk.