A swarm of jellyfish has caused major disruption at one of France's largest nuclear power plants, for the second time in a month.
The jellyfish entered the filters of the pumping station at the Paluel nuclear plant, France's national energy firm EDF said.
The incident reduced output at the plant in Normandy by 2.4 gigawatts, and crews are currently working to restore it to full operation.
In August, generation at another major nuclear site in France was also disrupted by jellyfish, after a 'massive and unpredictable' swarm forced the Gravelines plant to temporarily cease operations.
The hit represents a near halving of Paluel's 5.2 gigawatt output, following the shutdown of one reactor and the reduction of a second as a protective measure.
Nuclear energy accounts for about 70% of France's energy consumption, according to the World Nuclear Association (WNA).
Paluel is among France's largest nuclear power plants, with each of its four reactors generating over 1,300 megawatts of power.
EDF stated that they took measures at 21:00 local time (19:00 GMT) after the 'arrival of jellyfish' in the filters of the non-nuclear section of the plant.
The company added that its teams are 'carrying out the necessary diagnostics and interventions' to bring both reactors back online fully.
