French EDF Shuts Three Gravelines Reactors as Jellyfish Clog Cooling System
On August 11, 2026, French utility EDF halted three reactors at its Gravelines nuclear plant in northern France after a massive influx of jellyfish. Of the six reactors, only one now runs at full capacity, one at 50% power, one is under maintenance, and three are offline. EDF said the situation poses no safety or environmental risk. The plant faced a similar jellyfish-related shutdown in 2025, when it took about three days to restart the first reactor.
On August 11, French utility EDF said that a large influx of jellyfish had forced the shutdown of three reactors at the Gravelines nuclear power plant in northern France. Currently, of the plant's six reactors, only one is operating at full capacity, one is running at 50% power, one is under maintenance, and the remaining three are offline due to the heavy presence of jellyfish.
EDF stated that the current situation will not affect the safety of the plant's facilities, staff, or the environment. In 2025, the Gravelines plant also experienced a full shutdown after large numbers of jellyfish entered its cooling system, and it took about three days before the first reactor was restarted.
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