Heatwave: EDF warns of possible production cuts in the nuclear fleet from Wednesday

French electricity company EDF plans to reduce production at its nuclear power plants starting Wednesday, particularly at its Bugey power plant in the Ain department, due to the high temperatures expected in the coming days and the rising waters of the Rhône River.

"Due to forecasts of high temperatures in the Rhône, production restrictions are likely to affect EDF's nuclear production fleet from Wednesday, June 25, and more specifically the Bugey site," EDF indicated in an information message, specifying that these forecasts will be refined "on D-1."

Temperatures continue to rise in France, hit by an early heatwave, which has prompted Météo-France to issue an orange heatwave alert from Friday midday in 16 departments , mainly in western France.

The operation of the power plants, which pump water from adjacent rivers (or from the sea, where applicable) to cool them before releasing it warmer into the environment, is governed by heating and flow thresholds for these waterways that must not be exceeded. These thresholds are specific to each power plant and are intended to protect flora and fauna.

For several years, in a context of global warming , droughts and heat waves have led EDF, sometimes as early as June, to adjust its production to comply with these thermal discharge limits.

According to the group, since 2000, losses in nuclear production due to environmental causes (high temperature and low river flow) have represented on average 0.3% of the annual production of the nuclear fleet.

The country has already experienced two notable June heatwaves in recent years, one in 2019 and another, earlier, in June 2022. Global warming is making heatwaves earlier and later, more frequent, longer, and more intense.