Record-breaking nuclear power plants: UK pays the highest prices for new plants

LondonThe United Kingdom faces a decisive decade for its energy future at a time when most of its nuclear fleet is nearing the end of its lifespan due to aging. Currently, the country generates approximately 15% of its electricity from nuclear power, thanks to an installed capacity of around 6.5 gigawatts, generated by nine reactors at four plants. But all but one must be decommissioned by 2030. This has forced the British government to accelerate a political and financial commitment to a new generation of power plants, a commitment that is fraught with controversy and challenges. Currently, the UK is building two major projects: Hinkley Point C in Somerset and Sizewell C in Suffolk. Both, the first new plants built since 1988, symbolize both the ambition and the difficulties of the British nuclear model. With estimated costs reaching €54.57 billion for the first and €43.23 billion for the second, these plants have become some of the most expensive energy infrastructure projects in the world, as the Working Group on Nuclear Regulation, established by Keir Starmer the previous February, warned at the end of November of last year. The cost overruns and delays have been so significant that EDF, the French state-owned company in charge of building Sizewell C, has accumulated multimillion-euro losses and has demanded that the British government assume almost all the financial risk for the project to move forward. Hinkley Point C is expected to come online between 2030 and 2031; Sizewell C, in 2035-36. The Working Group also warned that the UK has become the most expensive country in the world to build a nuclear power plant, not so much because of the technology used, but because of an accumulation of environmental, safety, and administrative processes that, according to the report, often do not provide real benefits in terms of public health or environmental protection. The document denounced a regulatory culture that is excessively risk-averse, which has resulted in thousands of pages of environmental impact assessments and increasingly lengthy and unpredictable planning processes.

Comparison with France is inevitable, both because of the industrial model and the results for the end consumer. Across the English Channel, nuclear energy remains the backbone of the electricity system. With 57 operational reactors and the generation of about 63 gigawattsFrance generates around 70% of its electricity with nuclear power, a proportion unparalleled in Europe. This capacity allows the country to have a stable, low-emission energy supply, but it is also reflected in the price consumers pay. The most recent data – from the end of 2025 – indicates that the average price of domestic electricity in France is around €0.23–0.24 per kilowatt-hour, including taxes, while in the United Kingdom the average cost is around 27–28 pence per kilowatt-hour. In practical terms, this means that a British household pays significantly more for its electricity than a French household with similar consumption. The difference is not only due to the massive presence of nuclear power plants in France, but also to more direct tariff regulation by the state. Meanwhile, the British electricity market is highly liberalized and includes infrastructure, network, and new project financing costs in the bill.

Even so, it is in Germany where electricity is most expensive, representing the opposite extreme of the French model. After a long political and social process, the country culminated the shutdown of its nuclear power plants in 2023The decision was part of an energy transition strategy based on renewables, but it reopened the debate on security of supply and the impact on prices, especially at a time of tension in the European energy market, following the Russian invasion of Ukraine and all its consequences. If we add the war in Iran and the potentially catastrophic energy crisis that is brewing, the debate could become even more heated. The German case, in fact, is used by both proponents and opponents of nuclear power as an example of the risks and opportunities of abandoning this technology.

In the EU, less than 25% of electricity

Across the European Union, nuclear power still contributes approximately 22% to 24% of total electricity, although its share is declining. The aging of reactors, their gradual decommissioning in some member states, and the slow pace of new plant construction contrast sharply with the rapid expansion of wind and solar energy. France remains by far the leading nuclear power player, while many countries have opted for a combination of renewables, imports, and, in some cases, gas as a backup source. And now, gas supplies are at least threatened.

The challenges facing the nuclear industry are largely shared in the UK and the EU. The primary challenge is financial, as reactors require enormous initial investments and very long construction times, making state involvement almost inevitable. The second challenge is regulatory, with a delicate balance between safety, public acceptance, and administrative efficiency. And the third is strategic, because nuclear power must find its place in an electricity system increasingly dominated by renewables, energy storage, and digitalization. However, the British government argues that nuclear power is essential to guarantee energy sovereignty and achieve climate goals. Official plans aim to reach 24 gigawatts of nuclear generating capacity by 2050, which would cover approximately 25% of electricity demand. This horizon also includes small modular reactors, which promise greater cost control, and research into nuclear fusion, a high-risk field but with enormous transformative potential. In this regard, the Starmer government has committed €2.8 billion for the initial development of a small modular reactor designed by Rolls-Royce in Anglesey, North Wales. The debate, both in the UK and in Europe, is no longer just technological, but political. Deciding how much nuclear energy to use, who bears the cost, and how it will be reflected in electricity bills is ultimately a choice about the energy and industrial model states want to build amidst climate transition and growing pressure on the cost of living, which will be further exacerbated by the inevitable impact.