The production of French nuclear power "threatened by heat"

The French electricity giant, EDF, has closed this week nuclear reactors in two power plants in southern France because of the heat wave. Proponents of nuclear energy boast of their role in reducing the carbonization of energy production, but can this still be an energy of the future if the future will be warmer?

The hot weather this week, exceeding 40 ° C in many parts of the country, led EDF to stop the production of nuclear power plants Golfech (Tarn-et-Garonne) and Tricastin (Drôme).

Nuclear reactors require large quantities of water to cool them and about two thirds of the 58 French reactors are supplied with water by nearby rivers. Once the cooling is complete, the warmed water is released into the river. But recent droughts have lowered water levels in the Garonne and the Rhone and the heat wave has increased the temperature of the water.

EDF followed French regulations stipulating that, in order to protect plants and animals, the production of electricity must be reduced when the water temperature exceeded 28 ° C or when the level of the river and the flow were low. But he insisted that there would be no impact on the power supply.

"The supply of electricity is not at all threatened by intermittent shutdowns or power cuts," said Etienne Dutheil, head of nuclear production at EDF, the French daily Libération. "For comparison, in winter, we need 100 GW. This summer, we have never exceeded 60 GW despite the increasing use of air conditioning.

He added that nearly 20 of the 58 French reactors have been stopped for maintenance or refueling "without this affecting the balance of the network".

No need to panic
In the current state of things "there is nothing to panic, because the supply of electricity poses no threat in the short term," says Yves Marignac, nuclear specialist, spokesman of Negawatt, a non-profit organization working for energy efficiency.

But the risk of a power cut would increase if temperatures reached what is called the "big heat" in French nuclear energy when the reactor was no longer considered safe enough to operate.

"The production of electricity by reactors is threatened by heat waves, especially on rivers, as is the case in France where two-thirds are on rivers," says Marignac. "If the heat waves are more intense and more frequent, in the range of 45 On certain days, there is also a risk of equipment failure due to the" big hot ".

"We are not there yet, but as climate science says, there will be more heat waves. They could be longer and warmer, which means we could reach this stage in the years and decades to come. "

& # 39; Vulnerable to climate change & # 39;
The 58 French reactors currently represent more than 75% of its electricity needs. While its 10-year energy plan is expected to close 14 reactors by 2035, nuclear power remains an important element of the energy mix. Proponents of nuclear energy say it makes environmental sense because it does not produce carbon dioxide (CO2).

But anti-nuclear groups like Get out of Nuclear (nuclear output) seized the latest heat wave to show that "nuclear is vulnerable to climate change". Moreover, they claim that "it will not save the climate" because, for example, it produces greenhouse gases through the management of its waste, the construction of nuclear power plants and its processes. extraction and refining of uranium ore.

"Continuing this dangerous adventure is no longer an option," says the non-profit organization.

Etienne Dutheil of EDF maintains depleted water supplies and rising temperatures should not hinder the future of Palo Verde nuclear power plants in the Arizona desert.

"Its cooling is based on wastewater collected in nearby towns," says Marignac, "so there is no need for an adjacent river."

Nevertheless, the future will consist of more diversified sources of electricity.

"What we have to recognize today is that, whether it's nuclear energy or renewable energy, the electricity system will increasingly depend on weather conditions and will be increasingly threatened by climate change, "said Marignac. production, but we must also act on our electricity consumption. "

This means we need to better control our electricity needs, think about how we use them, turn off appliances, work on buildings to reduce the need for winter heating and cooling in the summer.

"We really need to think about the need to produce low-carbon electricity, but also to make our electrical system more robust to the kind of events we have today, which unfortunately is probably not as the beginning of extreme weather events. "