“Europe’s biggest nuclear power operator EDF, which manages France’s fleet of 57 reactors, is under pressure to show it can improve on its record of reactor construction. Recent projects have been severely delayed and hugely over budget, taking well over 10 years to complete.” – Financial Times, February 20, 2026).
There’s a new leader in the nuclear power plant cost overrun derby, and it isn’t even in the clubhouse yet. Britain’s Hinkley Point C — being built in Somerset by France’s government-owned Électricité de France (EDF) — is now going to cost at least £49 billion ($65 billion) if it goes into service in 2030 and another £1 billion ($1.3 billion) if the first unit is delayed to 2031. This equates to $10 million per megawatt–best case–with multiple years of waiting. Expect it to go up from here.
The two-unit, 3,200-MW French-designed European Pressurized Reactor (EPR) was announced in 2015 at a then-estimated price of £18 billion in 2015 pounds sterling. Construction began in 2016. The new cost estimate — which EDF purposely underplayed — came in a company news release last month of its 2025 financial performance. Buried deep in the release, EDF said of the project:
Schedule for the start of production by Unit 1 adjusted to 2030 and action plans for the electromechanical work; completion cost estimated at £35 bn (in 2015 sterling).
Of course, the plant won’t be paid for in 2015 currency, but in contemporary pounds (or dollars). The new estimate “compares with a previous ‘best case’ target of 2029, itself a two-year delay from an earlier timetable,” the Financial Times (FT) reported. “When the project was given the go-ahead in 2016, it was due to come online in 2025.”
FT added that EDF, “Europe’s biggest nuclear power operator, which manages France’s fleet of 57 reactors, is under pressure to show it can improve on its record of reactor construction. Recent projects have been severely delayed and hugely over budget, taking well over 10 years to complete.”
The EPR, originally designed by France’s Framatome, a joint venture of EDF (80.5%) and Mitsubishi Heavy Industries (19.5%), has had a troubled history. In Finland, work on the 1,600-MW Olkiluoto 3 began in 2005 by France’s Areva and German Siemens A for Finnish operator TVO, scheduled to go into service in 2009 at an estimated cost of €3 billion.
The project experienced a cascade of problems, many of them embedded in the design. The plant went into commercial service in 2023 at an estimated cost of €11 billion ($12 billion), at the time the most expensive single nuclear unit in history. The plant has operated well.
EDF’s Lost Luster
France itself has had a problematic adventure with the EPR. EDF’s Flamanville 3 EPR in France began construction in 2007 with an estimated date for full 1,600-MW of power in 2012. The plant reached full power in December. Commercial operation is expected this year. When that happens, Flamanville 3 will become the first French power reactor to come online in 23 years.
The project faced a series of technical hurdles. NuclearNewswire reported last December:
Originally estimated to cost €3.3 billion (about $3.9 billion), the project’s price has ballooned over the course of repeated delays and difficulties. In December 2022, EDF announced a new cost estimate of €13.2 billion ($15.5 billion). In January 2025, the French Court of Auditors released a new estimate that includes the interest accrued during construction: €23.7 billion (about $27.8 billion). In all, the project is set to enter commercial operation at a price tag anywhere from four to seven times its original budget.
Race for the Worst
The most expensive commercially operating reactors are Georgia Power’s two new units at its four-unit Vogtle site. Units 3 and 4 are two Westinghouse 1,000-MW advanced reactors. Construction began in 2009, with an estimated completion estimated at 2016 and 2017 at a cost of $14 billion combined. Unit 3 went into service in 2023 and Unit 4 in 2024, at a total cost of $36.8 billion, around 160 percent above budget, not to mention the time-value of money.
Could Hinkley Point lose its position in the cost overrun race? Watch out for Britain’s Sizewell C near the village of Suffolk. This EDF project calls for two — that’s right — 1,600-MW EPR reactors. It’s a Hinkley Point clone. Construction began in January 2024, while the financing packing was still being constructed. The planned operating date is 2035, although that depends on progress at Hinkley Point, which has priority.
The current estimated cost for Sizewell C is £38 billion ($50.6 billion). Don’t hold your breath on that. It could easily be the most expensive thermal generating plant ever built, eclipsing the Vogtle #3/#4 debacle.
In short, the “nuclear renaissance” is lacking a model for success going into its eighth decade. George W. Bush, Joe Biden, Donald Trump–the saga continues with the most regulated, most subsidized industry in the world.
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This is an edited and slightly expanded version of this post published by Kennedy Maize at Quad Report. A Washington, D.C.-based journalist, Maize has covered energy and environmental topics for more than 40 years.