Sizewell C

On 30 June 2020, ONR received an application from NNB Generation Company (SZC) Ltd for a nuclear site licence to construct and operate a twin EPR™ power station at Sizewell in Suffolk, adjacent to the existing Sizewell B station.

ONR inspectors have now completed their assessment of the Sizewell C (SZC) nuclear site licence application and a progress statement, published in July 2022, is detailed below.

In addition to a nuclear site licence, before it can start construction, the applicant must obtain a number of site-specific permissions from other regulators and Government, including environmental permits and planning permission in the form of a Development Consent Order (DCO) from the Secretary of State.

ONR's regulatory responsibility starts at the point of granting of a nuclear site licence. Should we decide to grant the licence, we will use the powers available under the site licence to require the licensee to request our permission for starting nuclear safety related construction at Sizewell C. Similarly, the licensee will be required to seek ONR’s permission to proceed to subsequent, key construction and commissioning stages up to the start of commercial operation.

Our publication Licensing Nuclear Installations provides guidance on the licensing process and the factors that we may take into account when reviewing an application for a nuclear site licence.

We have undertaken our assessment activities in accordance with the guidance provided in the Licensing of Nuclear Installations document and ONR's Safety Assessment Principles, Technical Assessment Guides and Technical Inspection Guides.

Progress statement – July 2022

On 11 July 2022, the Office for Nuclear Regulation (ONR) provided an update on its assessment of the nuclear site licence application for the proposed nuclear power station at Sizewell C in Suffolk.

Our licence assessment concludes that the application has met almost all the regulatory requirements set out in regulatory guidance.

Specifically, we are satisfied that NNB Generation Company (SZC) Ltd has put in place an organisational capability and associated arrangements suitable for licence granting and no issues have been identified regarding the suitability of the site which would prevent a licence being granted.

However, there are two outstanding matters which require resolution prior to the formal granting of a licence.

The first relates to the current ownership of the land, known as security of land tenure, which is yet to be acquired by the licence applicant.

The second issue relates to the current shareholder agreement which places control of key policies relating to safety and security with a holding company, NNB Holding Company (SZC) Ltd, rather than the licence applicant, NNB Generation Company (SZC) Ltd.

Engagement between ONR and the applicant has indicated that plans are in place to address both matters in due course.

When those matters are resolved, we would carry out a proportionate reassessment of the application, focused on the two outstanding matters and any other relevant licensing issues that emerge during the intervening period.

To build and operate a new nuclear power station in the UK, a number of site-specific permissions are required from regulators and government, and granting a site licence does not permit the start of nuclear-related construction on the site. The licence application is separate to a Development Consent Order [LINK to DCO announcement], considered by the Planning Inspectorate, which determines if overall proposed scheme is acceptable under national planning legislation.

NNB Generation Company (SZC) Ltd has also submitted applications for environmental permits to the Environment Agency.

Our regulatory responsibility starts at the point of granting of a nuclear site licence. If granted, we would use the powers within the licence to require the licensee to request our permission for starting nuclear safety related construction. Similarly, the licensee will be required to seek our permission to proceed to subsequent, key construction and commissioning stages up to the start of commercial operation and beyond.

More details on the ONR site licensing process are available in the Licensing Nuclear Installations guidance document.

* We have published the full Project Assessment Report detailing our assessment of the nuclear site licence application. A fuller suite of detailed assessment reports will be published in due course.

Outstanding licensing matters explained

Security of tenure

Our regulatory guidance Licensing Nuclear Installations states that a nuclear site licensee is expected to have ‘full rights of access to and control of’ the site upon which the nuclear site will operate.

This stems from a requirement in the Nuclear Installations Act (1965).

NNB Generation Company (SZC) Ltd does not currently have such rights to the land proposed for the Sizewell development and this will need to be resolved prior to licence grant.

It is understood from engagement with the applicant that plans are in place to address this matter in due course.

Constraints of the current shareholder agreement

As the licensee should be able to exercise effective day-to-day control over all activities on the licensed site, it is essential there is clarity on how that responsibility can be exercised.

The current shareholder agreement for the development phase of the Sizewell C project places control of key policies relating to safety and security with NNB Holding Company (SZC) Ltd, rather than the licence applicant.

This is inconsistent with our regulatory expectations so we will require control of such policies to rest with the applicant prior to the granting of a licence.

It is understood from engagement with the applicant that the necessary amendments will be made to address this matter in due course.