France shuts three nuclear reactors as heatwave affects cooling water

France's main energy provider, EDF, said three nuclear reactors had been temporarily shut down and eight others were running at reduced power because of a heatwave in France.

EDF told AFP that reactors at the Golfech, Bugey and Chooz plants had been shut down because of weather conditions and to comply with rules on cooling-water discharges intended to protect the environment. The plants are on the banks of the Garonne, Rhone and Meuse rivers respectively.

The source said the measure is required to avoid releasing too much heated water into rivers that are already warming during the heatwave. Power plants that are important to France's electricity production use river water to cool reactors, which warms the water before it is returned to the river.

France's economy ministry issued an exemption on Saturday from temperature limits for heating the Rhone around the Bugey plant. The ministry said the exemption was intended to ensure the security of the power grid and would be valid until July 20.

AFP said the shutdowns were the second time in recent weeks that EDF had stopped nuclear reactors because of extreme heat, after a record-breaking heatwave in France in June.

On Sunday, France was experiencing its third heatwave since May. AFP said more than a third of the country was under the national weather service's highest heat alert. More than 25 million people were facing temperatures that forecasters said could reach 41C, according to an AFP tally based on population data.

The heatwave has led some tourist sites to close early, caused event cancellations and shortened a stage of the Tour de France. AFP said wildfires have increased and drowning deaths have risen during the heat.

Since the end of May, France has faced repeated periods of intense heat. AFP said these have caused excess mortality and exposed infrastructure problems linked to extreme weather. The source said scientists have linked the increasing frequency of such extreme weather to human-caused climate change.