Nuclear power plant in France shuts down amidst intense heatwave conditions
In the midst of a prolonged heatwave, several nuclear power plants in France have either been shut down or reduced their output to prevent the rivers used for cooling from overheating. The extreme temperatures have pushed river water temperatures beyond regulatory limits, potentially causing harm to aquatic life and compromising the safety of the reactors.
The west French nuclear power plant Blayais, for instance, reduced its output on Sunday and again on Monday to prevent overheating of the Gironde estuary. Similarly, the Golfech nuclear plant was shut down on July 1, 2025, when the Garonne River reached its regulatory maximum intake temperature of 28°C. Other plants such as Bugey, which draws cooling water from the Rhône river, have also faced potential shutdowns during the heatwave.
The frequency of such operational adjustments is directly linked to the occurrence of heatwaves, which are becoming increasingly common with rising global temperatures. During the recent heatwave in early July 2025, nearly all French nuclear sites experienced some reduction, with about 7 GW of capacity offline at the peak of the heatwave due to cooling constraints and some scheduled maintenance.
Despite these disruptions, France’s power grid has remained largely stable and continues to export electricity, reflecting the country's considerable nuclear capacity margin and grid management capabilities. The annual impact on power production can be significant during hot summers, with forced shutdowns and deratings temporarily removing several gigawatts of nuclear capacity.
EDF, the French state-controlled utility company, has stated that the impact of the measures on power production due to the shutdown of Golfech, reduction of output at Blayais, and potential shutdown at Bugey is negligible. However, recurring heatwaves could strain this balance in the future.
The heatwave is expected to last until mid-week, with temperatures potentially reaching up to 40 degrees Celsius. The exact duration of the Golfech plant's shutdown remains unclear, as EDF did not specify how long the plant would remain offline. Similarly, no specific details were provided about the potential shutdown at the Bugey power plant or how long it might last.
Since 2000, an average annual reduction in power production has occurred due to the dimming or shutting down of nuclear power plants during heatwaves, amounting to 0.3 percent. This underscores the importance of addressing climate change and its effects on the operation of critical infrastructure like nuclear power plants.
[1] https://www.reuters.com/business/energy/frances-blayais-nuclear-plant-cuts-output-due-heat-2021-07-11 [2] https://www.nucleareurope.org/news/blayais-nuclear-power-plant-reduces-output-due-high-river-temperature [3] https://www.bbc.com/news/science-environment-57849955 [4] https://www.reuters.com/business/energy/frances-nuclear-output-falls-heatwave-2021-07-12
- The escalating instances of heatwaves, a symptom of climate change, have precipitated adjustments in the operation of nuclear power plants, as seen in France, where plants like Blayais and Golfech have reduced output or been shut down entirely.
- Considering the adverse effects of climate change on the environment, it's crucial to recognize the significance of nuclear power plants in energy production, as even minor annual reductions in power production, such as the average observed since 2000, can have substantial implications for the industry and the overall energy landscape.
- Finance and environmental science must collaborate to address climate change, ensuring that the energy sector, including nuclear power plants, can continue to function optimally and safely, while minimizing potential harm to aquatic life and other environmental concerns.
