Consultation and notice of proposed modifications to Sizewell C regulatory framework

Statutory consultation

We are consulting on proposed modifications to the Sizewell C regulatory framework, including amendments to the Special Conditions of the Electricity Generation Licence, Price Control Financial Instruments (PCFIs), and Cost of Debt Adjustment (CDA) Calculation Model.

The proposed changes are intended to ensure regulatory calculations can correctly reflect charging years that are longer or shorter than 12 months (the 17-month first charging year), prevent over- or under-remuneration, and improve consistency across the licence, PCFIs and CDA Calculation Model so that key revenue-setting and financial administration mechanisms operate as intended.  

Notice of proposed modifications

We are also asking for input on a notice of proposed changes by direction to the Sizewell C regulatory framework, including proposed modifications to the Price Control Financial Instruments and Cost of Debt Adjustment Calculation Model.

The proposed changes are considered necessary to correct errors of functionality and ensure the models function effectively in order to calculate the Allowed Revenue in accordance with the licence.  

Who should respond

• Sizewell C Limited
• current and prospective investors
• consumer representative bodies

How to respond

There is a single set of draft documents. Changes in the PCFIs and CDA Calculation Model that relate to the statutory consultation are coloured pink, while changes in the PCFIs and CDA Calculation Model that relate to directed changes in the notice are coloured blue.

Submit your separate responses to the consultation and the notice of proposed modifications by 13 August 2026 by emailing NuclearRAB@ofgem.gov.uk.

Some of the files attached below are not fully accessible. If you require an alternative format, please contact NuclearRAB@ofgem.gov.uk.