The Gravelines nuclear power plant in northern France has been forced to shut down after a massive swarm of jellyfish clogged the filter drums that draw in cooling water, its state-owned operator, EDF, has confirmed.
The facility, one of the largest in France, is cooled via a canal linked to the North Sea. According to EDF, four reactors were affected in the incident, which occurred late on Sunday, prompting a complete halt in production.
Reactors 2, 3 and 4 automatically shut down when the pumping station’s filter drums became packed with what EDF described as a “massive and unpredictable” influx of jellyfish. Reactor 6 was taken offline shortly afterwards. The remaining two units were already out of service for planned maintenance, meaning the entire plant is now offline.
Located on the coast between Calais and Dunkirk, Gravelines’ six reactors each generate 900 megawatts of power, producing a total output of 5.4 gigawatts. EDF stressed that the event had no impact on the safety of the plant, its staff or the surrounding environment.
Several jellyfish North Sea native
Several jellyfish species are native to the North Sea, often appearing in greater numbers along the shoreline during the summer months, when waters are warmer.
