From his humility Starting as a glacial drip in the Swiss Alps, the Rhône River is rapidly transforming into one of the most industrialized waterways in the world. As it meanders through the south of France into the Mediterranean Sea, its cold water is dragged into the boilers, sucked in by pipes as a coolant, diverted for agriculture. Its main customers include a battalion of nuclear reactors. Since the 1970s, the river and its tributaries have helped generate about a quarter of France’s atomic energy.
But the last few weeks have not been like that. Amid a slow heat wave that has killed hundreds and caused intense forest fires across Western Europe, and combined with already low water levels due to drought, the Rhône water has become too hot for work. It is no longer possible to cool reactors without expelling water downstream so hot as to extinguish aquatic life. So a few weeks ago, Électricité de France (EDF) began shutting down some reactors along the Rhône and a second major river to the south, the Garonne. It is now a known story: in 2018 and 2019 there were similar stops due to drought and heat. This summer’s cuts, combined with the malfunction and maintenance of other reactors, have helped reduce France’s nuclear power production by almost 50 percent.
Of all the low-carbon energy sources that are likely to be needed to combat climate change, nuclear power is usually considered the least disturbing. It is the reinforcement required when the climate does not cooperate for other zero-carbon energy sources, such as wind and solar. But the nuclear industry faces its own climate risks.
Problems with water, too much or too little, are more commonly associated with hydroelectric dams, which have struggled to keep production in dry places like the American West. But as the Swedish historian Per Högselius says, much of today’s nuclear engineering is not about splitting atoms, but about managing aquatic concerns on a larger scale. Nuclear technicians are known to refer to their boat as a very complicated way to boil water, producing steam that spins the turbines. But much more is usually required to keep the reactor cool. That is why so many facilities are located by the sea and along large rivers such as the Rhône.
Many other industries are affected by the hottest rivers, including large coal-fired power plants and power plants. But nuclear power plants are unique for their immense size and the central role they play in keeping power grids online in places like France. And warming and declining rivers are not the only climate challenges they face. On the coasts, a combination of rising sea levels and more frequent and intense storms carries a higher risk of flooding. Scientists have also pointed to other more unusual challenges, such as more frequent algae blooms and the explosion of jellyfish populations, which can clog water pipes.
Nuclear power plants are also built to last into the future, with a useful life spanning half a century or more. Many were built in the 1970s and 1980s, long before regulators thought they could take into account the climate-related threats they would eventually encounter, says Natalie Kopytko, a researcher at the University of Leeds who has researched nuclear regulatory frameworks to look for considerations. climatic conditions. “I saw absolutely nothing about climate change, which was pretty scary,” he says. Where Kopytko saw the weather being invoked, plans assumed that current weather patterns would be maintained in the future.