A swarm of jellyfish has caused the shutdown of one of France's largest nuclear power plants after clogging the water intake systems used for cooling. The Gravelines plant in northern France saw three reactors automatically shut down late on Sunday, according to operator EDF, as filter drums became packed with a 'massive and unpredictable' influx of the marine creatures.
The entire plant, which can power about 5 million homes, was taken offline when a fourth reactor shut down shortly after the jellyfish jammed the system. Two other reactors were already offline for planned summer maintenance. EDF, owned by the French state, stated that the event did not affect safety, staff, or the environment, and there was no change to electricity exports from France to the UK.
The Gravelines plant draws cooling water from a canal connected to the North Sea, where native jellyfish species are common in warmer summer waters. Jellyfish have a history of disrupting coastal power plants globally, prompting scientists at the University of Bristol to develop an early warning tool to predict such swarms.
In 2021, the Torness nuclear plant in Scotland, also operated by EDF, was forced to shut for a week due to jellyfish clogging water intake filters. Similar incidents have occurred at nuclear and coal plants in Sweden, the US, Japan, and the Philippines, where a 1999 jellyfish-related blackout was mistakenly linked to the Y2K bug. In September, eastern China's largest coal-fired plant battled for 10 days to clear over 150 tonnes of jellyfish from its cooling systems.
