France's flagship Flamanville nuclear reactor in Normandy was to start supplying electricity to homes on Friday when it's reconnected to the power grid after a dozen costly years of technical setbacks.
While Flamanville 3 will eventually power up to two million households, energy operator EDF said the reactor will not operate at full capacity immediately.
Instead, the operation “will be marked by different power levels through to the summer of 2025”.
The start of the new generation European Pressurized Reactor (EPR) comes 12 years behind schedule after a slew of delays and cost overruns.
The cost of the project, initially estimated at €3.3 billion, has ballooned to over €13 billion.
A test run in September had to be interrupted after one day due to an "automatic shutdown", before starting again days later.
Nuclear safety in spotlight as French start-ups bring mini reactors to market
Betting on nuclear
Flamanville 3 is the fourth EPR reactor in the world and the most powerful in France, with a capacity of 1,600 MW. It is the 57th reactor in the French nuclear fleet, which generates around three fifths of the country’s energy.
France continues to bet on nuclear as a way of providing relatively cheap and carbon-free electricity.
The government has committed to building six new-generation EPR2 reactors at a cost of tens of billions of euros, with plans to eventually increase this number to 14.
France to build more new generation nuclear reactors to reach green targets
But questions remain about EDF’s ability to deliver on its ambitions. The energy giant is already heavily in debt, as is the French state – EDF’s sole shareholder.
Nuclear power accounts for around three-fifths of France's energy output and the country boasts one of the world's largest nuclear power programmes.
Neighbouring Germany exited nuclear power last year by shutting down the last three of its reactors.
