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

New Regulatory Instructions and Guidance (RIGs) for Sizewell C (nuclear licensee): consultation | Ofgem Please enable JavaScript in your web browser to get the best experience. BETA This site is currently in BETA. Help us improve by giving us your feedback . Close alert: New Regulatory Instructions and Guidance (RIGs) for Sizewell C (nuclear licensee): consultation Publication type: Consultation Publication date: 23 July 2025 Last updated: 15 September 2025 Closed date: 20 August 2025 Status: Closed (with decision) Topic: Nuclear energy Show all updates Print this page Share the page Share on Facebook Share on Twitter Share on LinkedIn 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 . Respond name Timipre Haruna Respond email RABmodel@ofgem.gov.uk Main document Sizewell C (nuclear licensee): Overview of Regulatory Instructions and Guidance [PDF, 295.28KB] Sizewell C (nuclear licensee): RFPR Guidance [PDF, 424.65KB] Sizewell C (nuclear licensee): Revenue Workbook [XLSX, 439.04KB] Sizewell C (nuclear licensee): Cost and Schedule Workbook [XLSX, 1.54MB] Sizewell C (nuclear licensee): Regulatory Financial Performance Reporting (RFPR) template [XLSX, 4.64MB] Print this page Share the page Share on Facebook Share on Twitter Share on LinkedIn All updates New guidance published 15 September 2025: Sizewell C (nuclear licensee): Regulatory Instructions and Guidance (RIGs). Close