The Hinkley Point C (HPC) nuclear power plant is being developed by Électricité de France (EDF) in Somerset, UK. It is the first new nuclear plant to be developed in the country in more than 20 years.
The development consent order for the project from the UK government was received in March 2013.
EDF and the China General Nuclear Power Corporation (CGNPC) signed a strategic investment agreement for the construction and operation of the nuclear project in October 2015. EDF’s stake in the project is 66.5% and CGNPC’s stake is 33.5%.
The Nuclear New Build Generation Company (NNB GenCo), a subsidiary of EDF, was formed to build and operate the project. CGNPC will make its investment in the UK through its new company, General Nuclear International (GNI).
The final investment decision on the project was announced in July 2016. The plant’s first unit is expected to be operational in 2027.
The project was originally estimated to cost £16bn ($27bn). In February 2023, EDF announced that its cost is likely to increase to between £31bn ($37.2bn) and £32.7bn ($39.3bn) due to inflationary pressures.
The 3.26GW plant is predicted to produce 26TWh of electricity per year during its operational lifetime of 60 years, equivalent to 7% of Great Britain’s forecast electricity demand during the 2020s.
The power generated by the plant will meet the needs of six million homes and will offset nine million tonnes of carbon dioxide. The project is expected to create 25,000 jobs during construction and operation.
State aid controversy of Hinkley Point C
The Hinkley Point C project attracted much attention due to the state aid provided by the UK government in the form of a subsidy of £92.50 (approximately $156) for every megawatt hour (MWh) produced for a period of 35 years.
The European Commission (EC) conducted an investigation into the agreement and the subsidies given to the project. In September 2020, the EC approved the aid provided by the UK government, stating that it was within the EU’s rules on state aid.
Hinkley Point C power plant make-up
The power station’s 175-hectare site is on Somerset’s north coast at Bridgwater Bay, adjacent to the Hinkley Point A and B plants. Point C will be the first such plant to store spent nuclear waste on-site.
Two European pressurised reactors (EPR) with a power generation capacity of 1.6GWh each will be installed at the facility. Each reactor is designed for an operational life of 60 years. The reactors’ decommissioning is forecast to start in the 2080s and is estimated to continue for 20 years.
The first two EPRs were developed at Olkiluoto in Finland and Flamanville in France. The Olkiluoto 3 (OL3) nuclear reactor commenced operations in April 2023.
The heat generated from the reactors will be used to produce steam to power the turbines, directly connected to a generator. Each generator will be capable of producing 1.63GW of electrical power. The turbines are based on ARABELLE steam turbine technology and have a power output of 1.77GW.
The project also includes the construction of three tunnels under the Bristol Channel, including two 3.5km intake tunnels and one 1.8km outfall tunnel, to supply cooling water.
Construction of HPC
The construction of Hinkley Point C began in September 2016. The first concrete was poured for the power station’s galleries in March 2017.
The aggregate handling components were delivered at the project site via the vessel MPI Resolution in February 2019.
The construction of the base for the first reactor was completed in July 2019 and the first part of the second reactor, a 170t liner cup, was lifted into place in October 2020.
The first steel prefabricated ring for the first reactor was lifted in December 2020. The third and final liner ring was installed in December 2022.
Big Carl, the world’s largest crane, was used for installing heavy steel rings at the reactor’s buildings. The crane lifted the third and final liner ring over the project’s first reactor building in February 2023.
The first nuclear reactor pressure vessel was delivered to the plant site in February 2023.
The marine and offshore work on the power station’s cooling water system moved to its final stages in April 2023.
Decommissioning and waste management
Hinkley Point C is the first project in the UK to be included under a funded decommissioning programme. Under its terms, EDF Group is responsible for the plant’s decommissioning and its associated waste management costs.
Financing of Hinkley Point C power station
The UK government and EDF entered into a commercial agreement on the key terms of the proposed investment contract for the nuclear power project in October 2013. Terms include a strike price of £92.50 per MWh of energy produced, fully indexed to the Consumer Price Index.
The strike price is expected to come down to £89.50/MWh (approximately $151) with the start of EDF’s proposed Sizewell C site in Suffolk, England, which includes the installation of two more EPR units. It is proposed to share the EPR reactor technology across the two sites, reducing the strike price. The investment contract will be valid for 35 years from the date of commissioning.
The project falls under the UK guarantees scheme and debt funding of 65% of the estimated total cost will be provided under guarantee by the Treasury. This financing will be subject to due diligence by Infrastructure UK, a unit within the Treasury.
Equity finance is being provided by EDF Group, AREVA, CGNPC and the China National Nuclear Corporation (CNNC).
The project will have two substations for two units of nuclear power plants. The power produced will be transmitted to the national grid.
A new 400kV gas-insulated switchgear is being developed in Shurton to transfer the power produced from the Hinkley Point C plant to the national grid.
Contractors involved with HPC
GE Steam Power Systems, a subsidiary of General Electric, was awarded a $1.9bn contract for the supply of two conventional power islands for Hinkley Point C in September 2016. The conventional power island includes an ARABELLE™ steam turbine, a generator and related equipment.
ENKA UK Construction, a subsidiary of ENKA İnşaat ve Sanayi, was subcontracted by GE Steam Power to prefabricate, install and erect piping systems for the power plant in September 2021.
Framatome, a nuclear engineering company, was contracted to supply conventional field instrumentation, two nuclear steam supply systems and emergency and safety equipment, along with components and equipment including valves.
SNC-Lavalin Group, an engineering, procurement and construction services company, was chosen by NNB GenCo to provide engineering and technical services, while Atkins, part of the SNC-Lavalin Group, was chosen to provide the detailed design of technical galleries and classified and unclassified buildings. Atkins is providing design services to the project, utilising the 3D RC services of Tekla, which is part of Trimble, an industrial technology company.
Atkin also contributed to acquiring a nuclear site licence for the project.
A consortium of construction companies, Laing O’Rourke and Bouygues TP (Bylor), was awarded the contract for civil engineering works for the construction of buildings to accommodate two nuclear reactors for the project.
Bouygues was contracted to design and build the simulator training centre and a warehouse for the project. The contract for manufacturing the backup plant was also assigned to Bouygues.
Jacobs Engineering Group, an engineering and construction services provider, is delivering project management services for the building and civil work at the construction site, along with marine services.
The contract for detailed engineering services for the construction of buildings at the project site was awarded to Ingerop, a construction engineering company, and its subsidiary, Rendel.
A consortium of Egis, a consulting and construction engineering company, along with Setec, an engineering and consulting group, and Tractebel, engineering and consulting services provider, is responsible for the detailed civil engineering design of the EPR nuclear island buildings.
Balfour Beatty, an infrastructure company, is delivering the tunnelling and marine works for the project.
Costain was awarded the marine works contract.
Areva, a company involved in the design and construction of nuclear power plants, Hanson UK, a heavy building materials supplier, ABB, a technology company, KAEFER, a plant integrity services and solutions provider, and Dextra, a construction engineering company, are also involved in the project.
Other contractors are Rolls-Royce, a power systems manufacturer, Mitsubishi Heavy Industries, an electrical equipment and electronics company, Sarens, a heavy lifting services provider, Gillespies, a landscape architecture firm and Weir Engineering Services, an engineering solutions company.
Ovivo UK, a water treatment solutions provider, KBR, a technology and engineering solutions provider, Telent, a technology company, William Hare, a structural steel engineering group, Nexans, a cables manufacturer, and construction and civil engineering companies Kier and BAM Nuttall are also involved in the project.
Other contractors include Arup, a professional services company, BioClad, a cladding supplier, Clarke Willmott, a law firm, AECOM, an infrastructure consulting firm, Thinkproject, a construction and engineering SaaS provider, Hydrock, an engineering design consultancy, Wood, a consulting company, and Mace, a construction firm.