A large influx of jellyfish into the seawater pumping stations at the Gravelines nuclear power plant on France’s northern coast forced the shutdown of three reactors on Monday, the operator EDF said on Tuesday.
At the Gravelines site, the largest nuclear power station in Western Europe, reactors 2, 3 and 4 were taken offline, while output from reactor 1 was cut to 50%.
Only reactor 6 is currently operating at full capacity. Reactor 5 was already shut down for scheduled maintenance, EDF said.
The company said the incident had no impact on plant safety, staff security or the environment.
The Gravelines facility faced the same problem exactly a year ago. At that time, four reactors shut down automatically because of the incident, and the restart was gradual. The last reactor was reconnected to the national grid only after around 10 days.
Jellyfish are a regular seasonal presence along the northern French coast, but reports of large swarms in the area each summer are becoming more frequent, according to an expert interviewed by AFP last year.
A number of factors are driving the global spread of jellyfish, including rising ocean temperatures linked to climate change.
