A nuclear power plant in northern France was forced to shut down after a massive swarm of jellyfish clogged its water intake systems, used for cooling the reactors. The Gravelines plant, which can power 5 million homes, automatically shut down three of its four reactors due to the “unpredictable” invasion of the marine creatures.
The incident did not affect the safety of the facilities, staff, or environment, according to French nuclear company EDF. The plant draws water from a canal connected to the North Sea, which is home to native species of jellyfish that appear during warmer summer months.
Jellyfish have been known to disrupt coastal power plants, and scientists at the University of Bristol developed an “early warning tool” to predict sudden, en masse appearances of jellyfish swarms. This incident is not an isolated one; similar problems have occurred at other nuclear and coal power plants in Sweden, the US, Japan, and even led to a major blackout in the Philippines in 1999.
In recent years, unexpected jellyfish surges have forced workers to battle with massive quantities of marine creatures, such as in eastern China’s largest coal-fired power plant, where over 150 tonnes were cleared from the plant’s cooling systems. The incident highlights the need for preparedness and monitoring to mitigate the impact of jellyfish on coastal infrastructure.
Source: https://www.theguardian.com/world/2025/aug/11/swarm-of-jellyfish-shuts-nuclear-power-plant-in-france