High temperatures in river water are reportedly forcing Electricite de France SA (EDF) to cut power generation at some of its nuclear plants. The news is particularly troubling as several European nations struggle to cope with an energy crisis caused by gas cuts made by Russia in retaliation against sanctions placed on it due to the war in Ukraine.
River water is often used in many parts of the world to cool steam condensers at all types of thermal power plants, including at nuclear, coal, and gas-fired units. The water picks up heat as it passes through the condenser and returns to the river. However, regulators often place temperature restrictions on the cooling water to prevent harm to the environment, which could be caused if limits were exceeded.
Extreme heat and the driest July on record in France have caused river temperatures to reach certain thresholds that restrict nuclear plant output at some sites. [Many sites have reduced the power to meet limits]
Production from the French nuclear fleet has also been affected by ongoing maintenance at half of the countries 56 reactors. At least some of the maintenance was spurred by the discovery of stress corrosion cracking on the Civaux Unit 1 reactor at the end of 2021. Since then, EDF has carried out a considerable amount of work to more clearly understand the phenomenon and identify the zones concerned. It intends to inspect all of its reactors by 2025, but has prioritized inspection of the most susceptible zones of the N4 and P’4 reactors.