French nuclear power plant decommissioned in the cooling system due to jellyfish

French nuclear power plant decommissioned in the cooling system due to jellyfish

On Sunday, four reactors in the Gravelines, French nuclear power plant were switched off due to a collection of jellyfish in the cooling systems, as the operator Edf announced on Monday. This situation is probably due to rising water temperatures as a result of global warming.

The Graveline's nuclear power plant

The power plant in northern France is one of the largest in the country and is cooled over a channel connected to the North Sea. The six units each produce 900 megawatts of electricity, a total of 5.4 gigawatts.

production temporarily stopped

The entire system has now temporarily stopped production because the other two units for planned maintenance work are offline, as the data from EDF show.

jellyfish plague and their causes

The beaches around Gravelines, between the larger cities of Dunkirk and Calais, have seen an increase in jellyfish population in recent years, which is due to the heating of the water and the introduction of invasive species.

"Allen multi -faster when the water is warmer and that areas such as the North Sea get warmer, the reproductive window is getting bigger," explains Derek Wright, Mariner Biologist at the National Oceanic and Atmospheric Administration Fisheries.

"Jumps can also ride with cargo ships by getting into the ballast tanks of the ships in a port and often pumping out in the middle of the ocean," he added.

The appearance of the Asian lunar whereabouts

An invasive way, known as the Asian moon jelly, which originally dates from the Northwest of Pacific, was first spotted in the North Sea in 2020. This type, which prefers the standing water with high animal planton concentrations such as in ports and channels, caused similar problems in ports and nuclear power plants in China, Japan and India.

"Everyone is talking about nuclear energy, but we don't think of the unintentional consequences of heat pollution," emphasizes Derek.

Safety of the systems

Edf initially did not respond to an inquiry for a comment. The reactors 2, 3 and 4 in Gravelines automatically stopped shortly before midnight, when the filter drums of the pumping stations were clogged with a "solid and unpredictable" swarm. Reactor 6 went offline several hours later, as the EDF report holds.

The event had no effect on the safety of the systems, the employee or the environment, according to the announcement. The nuclear power plant is also close to beaches that have become hotspots for migrants who try to get to Great Britain. The invasive jellyfish do not represent a threat because they have no toxic stitch.