Sizewell C nuclear power plant

Details of proposals for Sizewell C, a proposed nuclear power plant in Suffolk.

The Sizewell C application was granted development consent on 20 July 2022, by the Secretary of State for Business, Energy and Industrial Strategy.

Suffolk County Council has been a statutory consultee and has evaluated, challenged, and commented upon the proposals for a new nuclear power station to get the best possible outcomes for the people of Suffolk.

If and when the project is being commenced, the Council will have key roles in discharging requirements, monitoring and managing the monetary mitigation contributions by SZC Co held by the Council.

This page provides details of key documents related to the consent and related to the examination, as well as an overview of the history of the proposals.

Further details of the proposals are available on EDF Energy’s Sizewell C pages and on the Planning Inspectorate Sizewell C website.

Contact details


The Development Consent Order (DCO) as made by the Secretary of State. This is the legal instrument for the consent of the proposal.

Within the DCO, requirements are set out which will be discharged either by Suffolk County Council (in relation to Highways, Public Rights of Way and Archaeology) or East Suffolk Council. Where Suffolk County Council discharges requirements, this will be published on the County Council’s Planning Register.

Sizewell C Deed of Obligation

Suffolk County Council agreed with SZC Co and East Suffolk Council a funding package for mitigation and compensation measures for the construction and in some cases into the operational phases.

This has been agreed in a Deed of Obligation (which is the equivalent to a Section 106 agreement), which was signed by the three parties before the close of examination.

Since the signing of the Deed of Obligation, two Deed of Variations have been signed which amend specific aspects of the original Deed.



Between April and October 2021, an Examining Authority appointed by the Planning Inspectorate held an examination into the proposals for Sizewell C.

Suffolk County Council has been a statutory consultee and has evaluated, challenged, and commented upon the proposals for a new nuclear power station to get the best possible outcomes for the people of Suffolk.

All documents submitted during the Examination by Suffolk County Council, the Applicant and other Interested Parties are published on the Planning Inspectorate website.

On 12 October 2021, Suffolk County Council submitted its Final Position Statement to the Examining Authority, at the end of the examination. Read the Final Position Statement.

In November 2009 the government announced that Sizewell, amongst other sites, would be a suitable location for a new nuclear power station.

In 2011 the National Policy Statements for Energy Infrastructure were approved. These contain the policies by which applications for major energy projects are judged, and as such, are relevant to the Sizewell proposals.

The key milestones in the planning phase of the proposed new power station



Stage One consultation: EDF Energy set out the background and context to the development

Completed on 6 February 2013

Stage Two consultation: a second formal stage of consultation

From 23 November 2016 to 3 February 2017

Stage Three consultation: a third stage of formal consultation

From 4 January 2019 to 29 March 2019

Stage Four consultation: a fourth stage of formal consultation, supplementary to the stage three consultation, focusing on specific issues

From 18 July 2019 to 27 September 2019

Submission of Development Consent Order (DCO) to the Planning Inspectorate

27 May 2020

Section 56 consultation (invitation to register as an Interest Party and submit Relevant Representations to the Planning Inspectorate)

From 8 July to 30 September 2020

Examination of the DCO by an Examining Authority appointed by the Planning Inspectorate

15 April to 14 October 2021

Decision by the Secretary of State (SoS)

20 July 2022

During the examination and pre-application phases, Suffolk County Council submitted a large number of representations and commissioned several studies as supporting evidence. Key documents are included in this section.

Suffolk County Council and East Suffolk Council are working together to respond to EDF Energy’s proposals. Further information about the two councils’ work on Sizewell C including their formal joint responses to the Sizewell C pre-examination consultations are available on the joint local authority page on

Local Impact Report

Suffolk County Council and East Suffolk Council submitted on 12 May 2021 their joint Local Impact Report to the Planning Inspectorate, as a key examination document.

The Local Impact Report sets out the Councils’ assessment of the likely impacts of the proposed development, and considers whether the proposed mitigation is appropriate or additional mitigation is required.

The submission to the Planning Inspectorate includes also a significant number of Annexes and Appendices, which are being published on the Planning Inspectorate website.

Read the Joint Suffolk Local Impact report (PDF, 3.6MB).

Suffolk County Council’s Relevant Representation

In advance of the commencement of the examination, the Council submitted its Relevant Representation to the Planning Inspectorate on 28 September 2020, following a debate and decision at a meeting of the Council’s Cabinet on 22 September 2020.

The Relevant Representation provides a summary of the Council’s views on the proposals put forward in the Development Consent Order (DCO) application and identifies the key topics and issues have the Council wishes to see addressed during the examination stage.

Read Suffolk Council Council’s Relevant Representation (PDF, 513KB).

Review of Sizewell C Bat Impact Assessment

Suffolk County Council and East Suffolk Council, working closely with the Suffolk Wildlife Trust, commissioned an independent review of the bat impact assessment.

This review will inform the Councils’ discussions with EDF Energy, in order to improve the Sizewell C proposals for mitigation to ensure they will not have a significant adverse effect on bats.

Read the:

Sizewell C Power Export Connection review

In light of Suffolk County Council’s concerns about the proposed introduction of four additional pylons and overhead lines as part of the Sizewell C proposals, and the resulting impacts on the Suffolk Coast and Heath Area of Natural Beauty (AONB), the County Council commissioned a high level independent report into the feasibility of alternative export connections avoiding pylons, to feed into the County Council’s responses to the Planning Inspectorate.

Read Sizewell C Power Export Connection review (PDF, 271KB)

Review of EDF Energy’s rail proposals for the Sizewell C development

Suffolk County Council commissioned an independent report into possible options to increase deliveries of materials by rail in response to the proposals put forward by EDF Energy in its Development Consent Order application, to feed into the County Council’s responses to the Planning Inspectorate.

Read the:

Accommodation Campus report

Following the EDF Energy Stage Two public consultation and Suffolk County Council's ask that EDF review potential alternative sites for the Accommodation Campus, the County Council commissioned an independent report as our contribution to this review.

Read the Accommodation Campus report (PDF, 4.5MB).