Cooling Towers Key to Nuclear Plant Resilience in Heatwaves

France is facing significant challenges with its nuclear power generation as three plants are currently offline due to cooling issues exacerbated by hot and dry weather. Low river water levels have made it impossible to adequately cool the reactors, leading to reduced output or complete shutdowns at several facilities. The Beznau plant, for instance, is offline to prevent the Aare river from becoming too warm.

These cooling problems, however, do not signal the end of nuclear energy but rather highlight the limitations of direct river cooling systems. Nuclear power plants equipped with cooling towers, such as those in Gösgen and Leibstadt, can continue operating even under extreme heat and drought conditions. The author argues that new nuclear plant constructions should incorporate such cooling towers as a standard feature.

While these plants do use river water for secondary cooling and to compensate for evaporation in cooling towers, the amount of water lost to the river is negligible compared to the overall flow. The primary concern with direct river cooling is the heat discharged into the water. Without cooling towers, the river could heat up significantly, impacting aquatic ecosystems. Cooling towers dissipate this heat into the atmosphere through steam.

Recognizing the issue, France's state-owned utility EDF has launched the 'Adapt' program. This initiative aims to retrofit plants, including installing smaller cooling towers, to cool water before it is discharged back into rivers. This measure is expected to prevent river heating and allow affected plants to continue operating through the summer, potentially avoiding production losses estimated at around 2% nationwide. The problem stems from having too many reactors situated on rivers with insufficient water flow to absorb the discharged heat.