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The controversial Hinkley Point C nuclear power plant

Hinkley Point C is one of the UK’s most ambitious and controversial infrastructure projects. The site, currently under construction by EDF on the Somerset coast, will eventually house two advanced nuclear reactors. Together, they’re expected to provide enough power for six million homes, supplying about 7% of the UK’s electricity.

Since construction began in 2017, the project has been hit by delays and costs that have far exceeded the original budget. The budget has more than doubled, rising from £18 billion to £40 billion, while the start date for electricity generation now has a target between 2029 and 2031.

This guide explores the most important and controversial aspects of Hinkley Point C. Here’s what we cover:

• Current status of the Hinkley Point C construction
• The cost of electricity from Hinkley Point C
• Hinkley Point C Ownership
• The European Pressurised Reactor design
• The environmental impact of Hinkley Point C

Current status of the Hinkley Point C construction

As of mid-2025, construction at Hinkley Point C has progressed significantly, with the main structures of both reactor buildings now complete.

In July 2025, the dome for the second reactor was fitted, marking a key milestone and the end of major civil engineering works. This allows installation of sensitive nuclear components to begin.

EDF expects that Reactor 1 will begin electricity generation between 2029 and 2031, with Reactor 2 following in the early 2030s, approximately three years behind the initial schedule.

Construction milestones

This timeline highlights the key milestones already reached in the construction of Hinkley Point C:

• September 2016: The UK government formally granted its final approval for Hinkley Point C.
• March 2017: Construction began with preparatory and site clearance works.
• June 2020: Construction of the base of the two reactors was completed.
• December 2023: The dome was fitted onto the Reactor 1 building.
• July 2025: The dome was fitted onto the Reactor 2 building.

The cost of electricity from Hinkley Point C

The rising cost of completing Hinkley Point C often makes headlines, but it’s worth noting that the project is funded by private investors, not the UK government.

However, the high construction costs are still expected to impact consumers in the long run, contributing to higher domestic and business electricity bills. Here’s how.

Contracts for Difference agreement for Hinkley Point C

To incentivise private investment in Hinkley Point C, the government has guaranteed the price of all electricity it will generate using the Contracts for Difference (CfD) mechanism.

The owners of Hinkley Point C are guaranteed to receive 12.7p/kWh for the electricity the plant generates, rising with inflation each year, for a 35-year period.

The CfD agreement for Hinkley Point C is significantly more expensive than both current wholesale prices and the strike prices agreed in the most recent CfD round in September 2024.

• Hinkley Point C:12.7p/kWh
• Offshore wind: 8.5p/kWh
• Onshore wind: 7.8p/kWh
• Solar: 7.1p/kWh
• Current wholesale price: ~7p/kWh

Sources: 2025 prices lowcarboncontracts.uk, the ICE exchange

Impact on electricity bills

Under the Contracts for Difference mechanism, the government will top up the current wholesale electricity market prices to the guaranteed price for 35 years.

The government top-up is funded through the CfD supplier obligation, which is paid on both domestic and business electricity prices.

A report by the National Audit Office in 2017, soon after the CfD terms were agreed, concluded that the cost to consumers would be £29.7 billion over the 36-year term.

However, since wholesale electricity prices have increased significantly since 2021, the overall cost is now likely to be lower.

As of August 2025, the wholesale market price of electricity is approximately 7p/kWh, which means the government is currently topping up by around 5p/kWh.

Since Hinkley Point C will produce approximately 7% of the UK’s electricity once operational, this results in a blended additional cost of 0.3p/kWh, or approximately £10 per year for the average household.

💡 At Business Energy Deals, we offer a free, no-obligation business electricity comparison service to help businesses get the best prices.

Hinkley Point C Ownership

The Hinkley Point C power station is being built by the private company NNB Generation Company (HPC) Ltd.

This company is ultimately part-owned by the following two organisations:

• EDF Group: Majority shareholder
• China General Nuclear Power Corporation (CGN): c.27% shareholding

These two parties have a strong track record of constructing nuclear power stations using European Pressurised Reactor technology, having partnered on the construction of Taishan 1 & 2, which went into operation in 2019.

In this section, we’ll dive into the involvement of these two organisations.

EDF Group

EDF (Électricité de France) is a French state-owned energy company and one of the world’s largest utility providers. It owns a controlling stake in Hinkley Point C and is the lead developer and operator.

EDF is a global leader in nuclear power, operating 56 nuclear reactors in France as well as all of the UK’s active nuclear power stations.

EDF’s UK business also operates large-scale offshore wind farms and gas-fired power stations, and is one of the biggest domestic and business energy suppliers (EDF business energy).

China General Nuclear Power Corporation

According to a disclosure on Companies House, Hinkley Point C’s shareholders include China General Nuclear Power Corporation Ltd (CGN), a state-owned Chinese enterprise.

CGN is a leading Chinese nuclear operator, responsible for operating over 50% of the country’s nuclear capacity.

The company has experience building and operating EPR reactors in China, notably at the Taishan Nuclear Power Plant in Guangdong, which became the first operational EPR in the world, bringing valuable technical expertise to the project.

However, the primary contribution of China General Nuclear Power Corporation has been financial, providing an early capital investment of £6–7 billion for the project’s development.

Ownership controversy and political concerns

The involvement of China General Nuclear Power Corporation, a Chinese state-owned enterprise, in the Hinkley Point C project has attracted considerable political and public scrutiny.

The partnership between CGN and EDF, established in 2015, was initially seen as a pragmatic solution to financing one of the UK’s most ambitious infrastructure projects, with CGN providing both capital and experience.

However, geopolitical tensions and growing concerns about national security have since reshaped the perception of Chinese investment in critical infrastructure.

Western governments, including the UK and the United States, have expressed unease over the potential risks of foreign state involvement in sensitive energy assets.

These concerns were heightened after CGN was added to the U.S. Department of Commerce’s Entity List in 2019, citing alleged attempts to acquire nuclear technology for military use.

The UK government has since bought out CGN’s stake in Hinkley Point C’s sister project, Sizewell C, citing the need to safeguard strategic autonomy in the energy sector.

The European Pressurised Reactor design

The Hinkley Point C nuclear power station is constructing a pair of third-generation pressurised water reactors using the European Pressurised Reactor (EPR) design.

The EPR technology offers enhanced safety, efficiency, and power output. Each reactor has a very high generating capacity, making Hinkley Point C one of the most powerful civil nuclear power stations in the world.

High power output

One of the defining characteristics of the European Pressurised Reactor (EPR) is its exceptionally high electrical output compared to earlier reactor designs.

The Hinkley Point C development is building two reactors, each capable of producing approximately 1,630 to 1,660 megawatts (MW) of electricity.

Individually, these reactors will have a higher output than any other nuclear reactor in the UK and can provide enough electricity to power around three million homes.

The European Pressurised Reactor features a larger reactor vessel and uses advanced steam turbines to generate electricity with higher thermal efficiency, allowing more energy to be extracted from each unit of uranium fuel.

Safety features of the EPR design

The European Pressurised Reactor (EPR) is a Generation III+ nuclear reactor designed with enhanced safety features compared to previous reactor designs.

Here’s a breakdown of the key safety features:

• Double concrete containment structure: The reactor is enclosed by two layers of concrete shells, providing additional protection against external events such as earthquakes, plane crashes, etc.
• Core capture system: Positioned below the reactor pressure vessel, this device is designed to catch and cool molten core material in the highly unlikely event of a core meltdown. It reduces the risk of ground contamination, as occurred at Fukushima.
• Four independent emergency cooling systems: The reactor is designed to be safely shut down and cooled even during system failure events. It features four independent cooling systems, each with its own power and control systems to provide redundancy.

These advanced safety systems offer industry-leading protection but have also introduced significant engineering complexity and challenging construction logistics, contributing to cost overruns and delays.

Construction delays

EDF is involved in the construction of three nuclear power stations in Europe using the EPR design, and all three have experienced significant delays and cost overruns, as summarised in the table below.

Extensive delays beset the first European EPR projects in Finland and France. These delays stemmed not from any single failure or from an inherent flaw in the reactor design, but from a combination of systemic challenges.

Here are the three most significant causes of the delays:

• Incomplete design at the start of construction: Building began before final engineering was complete, leading to rework and system integration issues at Olkiluoto 3.
• Complexity of safety systems: The advanced safety features of the EPR design introduced engineering and regulatory challenges far beyond those of previous reactor designs.
• Quality control and supply chain issues: Faulty welds, documentation gaps, and contractor coordination problems caused repeated delays.

The environmental impact of Hinkley Point C

The Hinkley Point C power station will have both positive and negative environmental impacts, which we explore below.

A low carbon source of power

Once constructed, the Hinkley Point C power station will provide the National Grid with a 3 GW source of baseload low-carbon electricity.

Nuclear power plants produce electricity through the process of fission, where uranium atoms are split to release heat. This heat is used to convert water into steam, which drives a turbine to generate electricity.

Unlike gas and coal power stations, this process produces zero direct carbon emissions.

While there are some emissions associated with mining and processing uranium, the overall carbon intensity is significantly lower than that of gas and coal power plants, which Hinkley Point C is intended to replace.

Baseload power for the grid

A key environmental advantage of the Hinkley Point C power station is the way its low-carbon electricity is delivered.

The output of nuclear power stations is consistent and can be relied upon year-round to supply a predictable amount of power to the grid, a characteristic known as “baseload power”.

The baseload power produced by Hinkley Point C will help to balance the growing contribution of intermittent power from UK wind farms, supporting grid stability.

For more information, read our blog on the current efforts to decarbonise the national grid.

Impact on marine life

One of the key reasons Hinkley Point was chosen as the site for the new nuclear power station is its proximity to the Bristol Channel, a large body of water.

The twin reactors at Hinkley Point C will require a supply of 130,000 litres of water per second to keep the reactors cool. Water will be drawn from the Bristol Channel, heated in the reactors, and then returned to the channel.

The Bristol Channel is one of the UK’s most biodiverse marine systems, home to migratory species and important fish nurseries. The construction and operation of the plant raise two key ecological concerns:

• Fish and larval entrapment: Marine organisms can be trapped and killed in the plant’s intake system. Environmental groups argue this may significantly impact local fish populations.
• Heated water discharge: The release of warmer water can alter local sea temperatures, potentially affecting the behaviour, breeding, or distribution of marine species.

Nuclear waste from Hinkley Point C

Like all nuclear power stations, Hinkley Point C will produce high-level nuclear waste in the form of spent uranium fuel rods from the reactor.

In line with standard industry practice, the waste produced at the site will initially be stored on-site in specially designed interim dry storage facilities. These facilities can safely store waste for several decades.

As a more permanent solution, the UK government is planning to build a Geological Disposal Facility, consisting of deep underground tunnels, to permanently dispose of waste from Hinkley Point C and other British nuclear reactors.

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