Jellyfish Infestation Forces Nuclear Plant To Shut Down

A swarm of jellyfish forced the shutdown of the Gravelines nuclear power plant in northern France on Sunday (August 10). The plant's operator, EDF, reported that the jellyfish clogged the filter drums of the cooling systems, causing four reactors to shut down automatically. The Gravelines plant, one of the largest in France, draws cooling water from a canal connected to the North Sea.

The plant's six reactors produce a total of 5.4 gigawatts of power, enough to supply electricity to approximately five million homes. However, with two reactors already offline for maintenance, the jellyfish swarm temporarily halted all production. The event did not affect the safety of the facilities, staff, or the environment.

The rise in jellyfish numbers is attributed to warming waters and the introduction of invasive species like the Asian Moon jellyfish. These conditions are exacerbated by global warming, which extends the reproductive window for jellyfish. Jellyfish swarms have historically disrupted operations at coastal power plants worldwide, including incidents in Scotland, Sweden, the United States, and Japan.

Efforts to mitigate such disruptions include developing early warning systems, as seen at the University of Bristol, which aims to predict jellyfish swarms that could impact coastal power plants.