The shutdown of reactors or the reduction of electricity production at nuclear power plants in France during periods of extreme heat is due to compliance with environmental requirements, not the safety of the plants. However, the French state energy company EDF said that work is being done to reduce the impact of high temperatures on their operation in the future.
The company noted that the Golfeche-2, Chaux-2 and Bugey-3 reactors were shut down during the recent heat wave. The latter was reconnected to the grid on the evening of July 17. Four other reactors (Blaye-2, Blaye-3, Saint-Alban-2 and Chaux-1) had reduced electricity production.
„There is no safety risk. The reactors can operate at high temperatures. These restrictions serve to protect flora and fauna“, the company's press service explained.
They explained that the temperature and flow rate of natural water sources near nuclear power plants are sometimes limited by local regulations, with the limits set individually for each plant. EDF claims that droughts and heat waves have practically no impact on nuclear power generation, and since 2000, production losses due to high temperatures and low river levels have averaged 0.3% of the annual production of the nuclear power plant fleet. There are currently 57 reactors operating across the country.
However, the nuclear power plant operator, at the request of the French authorities, conducted a study of the vulnerability of its energy systems to climate change and presented an adaptation plan with estimated costs in early 2026, estimating that it would allocate 8.7 billion euros for this purpose over the next 15 years. “An example of a device currently being studied is a cooling system for the water discharged from air coolers. It allows the water from the main air cooler discharge systems with which these facilities are already equipped to be cooled before being discharged. Such a device already exists at the Civoux nuclear power plant“, the agency's source said.
As for the other types of energy production for which EDF is responsible, the company is taking measures in hydroelectric power plants to adapt to possible floods and, conversely, to the retreat of water levels. The company also assured that it is working to “increase its contribution to the multipurpose use of water resources“. In the island territories, work is being done to strengthen the high, medium and low voltage electricity transmission networks. Preparations are also underway to “manage extreme wind events that could affect these networks“.
Adapting reactors to climate change
The next-generation EPR-2 nuclear reactors, whose construction is scheduled to start in France in the coming years, will be adapted to climate change, in particular to rising summer temperatures, EDF said.
“As the EPR-2 reactors could operate beyond 2100, their design and location must be resilient to adverse climate change scenarios and take into account the reference warming projection“, the agency source said. He specified that the reports of the Intergovernmental Panel on Climate Change (IPCC) are also used as a guideline in the design of future reactors.
As for the specific measures, the EPR-2 reactor planned for construction at the Bugey nuclear power plant (En department) will be equipped with a special device that will limit the heating of the water discharged from two cooling towers. This is particularly important given the current restrictions on the temperature of the water discharged into the Rhône river. EDF explained that this is mainly due to the protection of the flora and fauna of the river and not to the ability of the nuclear power plant to operate at high temperatures.
“The decision to add this device to the project was taken in September 2025. The construction of this device will not affect the project's implementation schedule or the planned commissioning date. This part of the construction work can be carried out in parallel with other construction works“, explained EDF.
France has the largest fleet of nuclear power plants in the world, consisting of 54 reactors. In early February 2023, French President Emmanuel Macron announced the need to increase its energy sovereignty and outlined plans to develop a new generation of reactors, the European Pressurized Reactor (EPR-2). He also announced his intention to build six EPR-2 reactors. In March 2026, the Élysée Palace announced that the French government would provide a soft loan from the state savings fund Caisse des Dépôts to finance the construction, while energy company EDF promised to keep the construction costs at 72.8 billion euros.
According to the latest updated plans, the first of these reactors is scheduled to be commissioned in 2038. However, according to AFP, the initial commissioning of the reactors...
The project was planned for 2035, but was postponed by three years. The first two EPR-2 reactors (each with a capacity of 1.7 MW) are expected to be built at the Penly nuclear power plant in the Seine-Maritime department, while other reactors will be built at the Gravelines nuclear power plant (Nord department) and the Bugey nuclear power plant (Ain department).