Flamanville 3: the reactor reaches its full power

The Flamanville EPR reactor reached a key milestone on December 14, 2025. At 11:37 a.m., it reached 100% of its nuclear power, producing 1,669 MW of gross electrical power. This milestone follows the authorization granted by the Nuclear Safety and Radiation Protection Authority on December 12.

This initial full-power test allows us to assess the proper functioning of the equipment. In the coming weeks, various experiments at different power levels will be conducted. Work is also planned on an internal electrical substation.

This success underscores the commitment of EDF's teams and its partners to a safe reactor start-up. This achievement is part of the group's strategy to support the energy transition.