Jellyfish swarm forces France's largest nuclear plant to shut down
Reactors 2, 3, and 4 at Gravelines stopped automatically just before midnight when the filter drums of the pumping stations became packed with a "massive and unpredictable" swarm of jellyfish, and reactor 6 went offline several hours later, the operator of the Gravelines nuclear plant said.
The automatic shutdowns of four units "had no impact on the safety of the facilities, the safety of personnel, or the environment", EDF said on its website.
The plant is fully shut after the incident, with its two other units already offline for maintenance.
Three of the production units automatically shut down late Sunday evening, followed by a fourth early Monday morning, said EDF.
"The plant's teams are mobilised and are currently carrying out the necessary diagnostics and interventions to restart the production units in complete safety," EDF said.
Gravelines is Western Europe 's largest nuclear power plant with six reactors, each with the capacity to produce 900 megawatts. The plant is due to open two next-generation reactors, each with a capacity of 1,600 megawatts, by 2040.
The beaches around Gravelines, between the major cities of Dunkirk and Calais, have seen an increase in jellyfish in recent years due to warming waters and the introduction of invasive species.
"Jellyfish breed faster when water is warmer, and because areas like the North Sea are becoming warmer, the reproductive window is getting wider and wider," said Derek Wright, marine biology consultant with the US National Oceanic and Atmospheric Administration Fisheries.
"Jellyfish can also hitch rides on tanker ships, entering the ships' ballast tank in one port and often getting pumped out into waters halfway across the globe," he said.
An invasive species known as the Asian Moon jellyfish, native to the Pacific Northwest, was first sighted in the North Sea in 2020.
The species, which prefers still water with high levels of animal plankton like ports and canals, has caused similar problems before in ports and at nuclear plants in China, Japan and India.
"Everyone talks about nuclear being clean but we don't think about the unintended consequences of heat pollution," Derek said.
EDF did not immediately respond to a request for comment.
The nuclear plant is also near beaches that have become hotspots for migrants attempting to cross into Britain. The invasive jellyfish are not considered a threat, as they do not have a poisonous sting.
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A nuclear plant in northern France was temporarily shut down on Monday after a swarm of jellyfish clogged pumps used to cool the reactors, energy group EDF said. Reactors 2, 3, and 4 at Gravelines stopped automatically just before midnight when the filter drums of the pumping stations became packed with a "massive and unpredictable" swarm of jellyfish, and reactor 6 went offline several hours later, the operator of the Gravelines nuclear plant said. The automatic shutdowns of four units "had no impact on the safety of the facilities, the safety of personnel, or the environment", EDF said on its website. The plant is fully shut after the incident, with its two other units already offline for maintenance. Three of the production units automatically shut down late Sunday evening, followed by a fourth early Monday morning, said EDF. "The plant's teams are mobilised and are currently carrying out the necessary diagnostics and interventions to restart the production units in complete safety," EDF said. Gravelines is Western Europe 's largest nuclear power plant with six reactors, each with the capacity to produce 900 megawatts. The plant is due to open two next-generation reactors, each with a capacity of 1,600 megawatts, by 2040. The beaches around Gravelines, between the major cities of Dunkirk and Calais, have seen an increase in jellyfish in recent years due to warming waters and the introduction of invasive species. "Jellyfish breed faster when water is warmer, and because areas like the North Sea are becoming warmer, the reproductive window is getting wider and wider," said Derek Wright, marine biology consultant with the US National Oceanic and Atmospheric Administration Fisheries. "Jellyfish can also hitch rides on tanker ships, entering the ships' ballast tank in one port and often getting pumped out into waters halfway across the globe," he said. An invasive species known as the Asian Moon jellyfish, native to the Pacific Northwest, was first sighted in the North Sea in 2020. The species, which prefers still water with high levels of animal plankton like ports and canals, has caused similar problems before in ports and at nuclear plants in China, Japan and India. "Everyone talks about nuclear being clean but we don't think about the unintended consequences of heat pollution," Derek said. EDF did not immediately respond to a request for comment. The nuclear plant is also near beaches that have become hotspots for migrants attempting to cross into Britain. The invasive jellyfish are not considered a threat, as they do not have a poisonous sting.
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