Nuclear power plants fear terrorist attacks, plane crashes and natural disasters. However, these same plants are now also facing quite unusual threats, including jellyfish. How is it possible ?
Salps, jellyfish and fish
The threats hanging over nuclear power plants are legion. In an article published on April 7, 2021, Bloomberg Green evokes one of these threats, the nature of which is quite surprising. The daily evokes the recent closure of two nuclear reactors in South Korea because of the presence of salps in the cooling system. Salps (or Salpidae) are gelatinous animals, ranging in size from one to ten centimeters. The latter look like jellyfish due to their consistency and their mode of travel. However, they would be closer to simple vertebrates, as they possess what appears to be a primitive form of nervous system.
In this case, the salps accumulated in such large numbers that the filter of the circuit of the two South Korean reactors was blocked for several days. However, it turns out that this incident is the second in just a few weeks. South Korea has therefore imagined a grinding robot, the Jellyfish Elimination Robotic Swarm (Jeros) capable of grinding 900 kg of salps per hour !
In 2012, a California nuclear power plant also shut down production for a while because of the salps. A year later, a jellyfish invasion in Sweden damaged the cooling water filters at a power plant. In France, the Paluel plant (Seine-Maritime) suffered a drop in production in January 2021 due to the presence of a school of fish.
Global warming involved?
Whether salps, jellyfish or fish, incidents like this tend to multiply. However, some believe that global warming may play a role in this phenomenon. The problem lies in the proliferation of these marine organisms. Fish farms are also affected by invasions of salps and jellyfish. A South Korean study published in 2012 estimated between $ 68.2 million and $ 204.6 million the losses these animals cause to the fishing industry.
In addition, global warming is the cause of increasingly frequent heatwave episodes. However, these have an effect on nuclear power plants, particularly in France where EDF has already been forced to close this type of establishment. The aim was to make sure not to exceed the legal temperature threshold for rivers, the latter serving for cooling. In a publication in 2020, the French Nuclear Energy Company (Sfen), however, affirmed that all energies are in the worst case led to reduce their production in the event of a heat wave. This also concerns the renewable energy sources that are solar, wind and hydroelectricity.