NEW NUCLEAR BUILD LEGAL APPROVALS – HINKLEY POINT C AND SIZEWELL C

1. Legal Framework for New Nuclear Construction

Building a new nuclear power station in England requires several separate but interconnected legal approvals. The principal regimes include the Planning Act 2008, Nuclear Installations Act 1965, environmental permitting legislation, the Energy Act 2013, electricity licensing rules, and environmental and habitats law.

A nuclear developer cannot rely on one general authorisation. It normally requires a Development Consent Order (DCO) for planning, a nuclear site licence from the Office for Nuclear Regulation (ONR), environmental permits from the Environment Agency, and further regulatory permissions as construction and commissioning progress. ONR must be satisfied about the proposed installation's safety case, site suitability and the applicant's ability to comply with nuclear licence conditions.

2. Development Consent Order

A large nuclear generating station constitutes a Nationally Significant Infrastructure Project (NSIP) under the Planning Act 2008. Consequently, its principal planning approval is obtained through the DCO system rather than ordinary local planning permission.

The DCO can authorise the generating station and associated infrastructure, while incorporating environmental requirements, mitigation measures and other legally enforceable conditions.

For Hinkley Point C, development consent was granted in March 2013 through the Hinkley Point C (Nuclear Generating Station) Order 2013. The Order expressly grants development consent subject to its requirements and approved plans.

For Sizewell C, the Secretary of State granted the DCO on 20 July 2022, authorising construction, operation, maintenance and eventual decommissioning of the proposed nuclear generating station.

3. Nuclear Site Licensing

The Nuclear Installations Act 1965 requires nuclear installations to operate on licensed sites. ONR therefore independently assesses nuclear safety, organisational capability and site suitability.

Hinkley Point C received its nuclear site licence in November 2012. Importantly, the licence does not amount to unrestricted permission to construct everything immediately. ONR operates a continuing permissioning regime, requiring regulatory approval at important stages of safety-related construction, installation and commissioning.

Sizewell C received its nuclear site licence in May 2024, after ONR concluded that its application satisfied the applicable licensing requirements.

4. Environmental Approvals

The Environment Agency separately regulates radioactive substances, water discharges, combustion activities and other environmental consequences.

For Hinkley Point C, three principal operational environmental permits were issued in March 2013, covering radioactive waste, standby diesel generation and cooling-water/liquid-effluent discharges. The permits have subsequently been varied as the project has developed.

For Sizewell C, environmental permitting similarly operates alongside planning and nuclear-safety regulation. The Environment Agency emphasises that environmental permits, DCO approval and the nuclear site licence are legally distinct permissions.

5. Case Law – R (Together Against Sizewell C Ltd) v Secretary of State for Energy Security and Net Zero [2023] EWCA Civ 1517

Facts: Together Against Sizewell C challenged the Secretary of State's 2022 DCO for Sizewell C. Among the central concerns was the proposed nuclear station's need for a permanent supply of potable water and the environmental assessment of how that supply would be provided.

Legal Issue: Whether the Secretary of State had lawfully undertaken the required assessment, particularly under the Habitats Regulations, despite uncertainty surrounding the permanent water-supply solution.

Judgment: The Court of Appeal rejected the challenge and upheld the lawfulness of the decision-making approach.

Legal Principle/Ratio Decidendi: Infrastructure consent does not necessarily require every future operational detail to have reached final design at the DCO stage. The legal question is whether the decision-maker has complied with the statutory assessment regime and has an adequate basis for concluding that relevant environmental requirements can be satisfied.

Significance: The judgment demonstrates how courts scrutinise major nuclear approvals while recognising the staged and technically complex character of infrastructure regulation.

6. Case Law – R (Together Against Sizewell C Ltd) v Secretary of State [2023] EWHC 1526 (Admin)

Facts: At first instance, the claimant sought judicial review under section 118 of the Planning Act 2008 of the decision to make the Sizewell C Nuclear Generating Station Order 2022. Seven grounds were pursued before the Planning Court.

Legal Issue: The grounds concerned the legality of the Secretary of State's environmental and planning assessment, including questions surrounding water supply and habitats protection.

Judgment: Holgate J refused permission to proceed on the grounds advanced. The water-supply issues subsequently proceeded to the Court of Appeal.

Legal Principle/Ratio Decidendi: A DCO decision is judicially reviewable, but the court's function is to determine legal compliance, not to substitute its own infrastructure-planning judgment for that of the statutory decision-maker.

Significance: The litigation confirms that even strategically important nuclear projects remain subject to environmental law, statutory planning requirements and judicial review.

7. Conclusion

Hinkley Point C and Sizewell C demonstrate that UK nuclear development operates through multi-layered legal approval. Planning consent under the Planning Act 2008, ONR nuclear licensing, Environment Agency permits, habitats assessment and continuing regulatory permissions perform different functions. The system therefore combines national energy-policy objectives with nuclear safety, environmental protection, public participation and judicial oversight, ensuring that obtaining a DCO is an important milestone rather than the end of regulatory supervision.