Electricite de France SA is preparing its nuclear power facilities to operate in more severe heatwaves in the coming decades as a changing climate may interfere with key electrical equipment.

The utility, which produces almost three-quarters of France’s electricity from its 58 nuclear reactors, is under pressure from the country’s atomic safety authority to improve the resilience of its power stations against rising temperatures and potentially more frequent natural disasters connected with climate change.

IRSN, the watchdog’s technical adviser, recommended in February that EDF take into account hotter and longer heat waves when it seeks approval to extend the lifetime of its reactors. Sustained, higher temperatures could damage key equipment, such as back-up diesel generators, the company said.

Power Outages

The French utility was forced to halt some of its atomic plants during an unprecedented heat wave in August 2003. Since then, it has added venting and air conditioning systems to protect electrical equipment and hardware. It has also improved the performance of water cooling towers. New safety equipment was also added in response to a nuclear plant accident caused by a tsunami in Japan in 2011.

“These works are quite considerable, especially because we’re trying to limit downtime,” Cecile Laugier, the head of environmental issues at EDF’s nuclear division, told journalists in Paris Tuesday. Climate change may lead to “potentially more frequent and more violent events.”

EDF’s efforts to mitigate the effect of warmer weather on its nuclear power output has already helped reduce unplanned outages. In 2003, reactor halts caused by the heatwave reduced the company’s French nuclear production by 1.7%. Last year, the loss of nuclear output was just 0.7%, according to Laugier.

Climate Experts

Power plants typically need cooling water that’s usually brought in from a nearby river or the sea before it’s returned at a higher temperature than when it came in. There are limits on how warm the water can be in order to protect fish and other aquatic life.

In 1999, EDF had to increase the height of some seawalls after its Blayais plant near Bordeaux was partly flooded by water coming from the Gironde estuary during a storm.

Since then, the company has created a team of 15 climate experts to better predict the impact of a changing climate on its operations and the surrounding environment. The team, formed in 2015, studies several metrics including river temperatures, wind and solar power output, sea levels and the resilience of its power plants to flooding and lightning.

“Today, climate and environmental issues are part of day-to-day activities,” Bernard Salha, EDF’s head of research and development, said Tuesday.

Copyright 2020 Bloomberg.