Flamanville-3

Flamanville-3 is France's first third-generation EPR pressurised water reactor, located at the Flamanville nuclear site in Normandy on the English Channel coast. After years of construction delays and cost overruns, it was connected to the grid in late 2024. The reactor has a design capacity of 1,650 MW and is operated by EDF. A Major planned overhaul is scheduled to Begin in September 2026 and is expected to last approximately one year, effectively removing the reactor from EDF's production base through most of the 2026-27 refill season.

Flamanville-3 was originally scheduled for completion in 2012 at a cost of EUR 3.3 billion. The final cost exceeded EUR 13 billion and completion was delayed by more than a decade, becoming a cautionary case study in nuclear project management cited by critics of new-build programmes across Europe and beyond.

Despite its operational challenges, the EPR design forms the basis of France's planned new-build programme: EDF has received government approval for up to six new EPR2 reactors (a refined design), with Penly as the first site. Flamanville-3's operational experience feeds directly into EPR2 engineering and regulatory approvals, making the current overhaul strategically as well as operationally significant for French energy policy.