Due to modulation, EDF reduced its production by 31 terawatt-hours in 2024, then by 33 TWh in 2025. "Part of this modulation was implemented by EDF to save fuel (18 TWh in 2024)," the report's authors specify — faced with low electricity prices, the energy company prefers not to produce in order to avoid using its uranium. The remainder, i.e. 13 TWh of modulation, "was carried out exclusively due to a lack of economic outlets."
Modulation could reach 42.5 TWh in 2028, according to the study's authors, if consumption does not increase — a sharp rise, therefore. "Last year, we produced 373 TWh of nuclear electricity and we had a producible capacity of 410 TWh," says Bernard Fontana, without estimating the lost revenue for the group.
To top it all off, the nuclear fleet is not the only one affected: EDF's hydroelectric dams and gas-fired power plants are also modulating, which further complicates the calculations. The transmission system operator (RTE) has estimated the economic effects of this overcapacity on the entire French electricity system at €20 billion per year, under a slow decarbonization scenario. Hence the persistent response from EDF and the government: electricity use must be expanded, with a target of increasing consumption by 150 TWh by 2035.
No safety concerns
"The safety of our facilities is preserved" in the event of modulation, Bernard Fontana reassures. The CEO then outlined the solutions to be implemented to limit these production variations. The first is "electrification of industrial uses." The process is underway "at ArcelorMittal, Aluminium Dunkerque… In total, there are six hundred electrification projects, and new projects such as the Safran plant," Bernard Fontana lists. Another lever is the establishment of data centers. "EDF is the third-largest landowner in France; we have sites to accommodate them quickly," the CEO states. The public group is also banking on the electrification of transport (electric cars and heavy goods vehicles) and building heating through the development of heat pumps.
To better align consumption with production, other mechanisms are also being activated, such as the introduction of new time slots for off-peak and peak hours, the development of stationary batteries, and the modulation of renewable energy. "More solar and wind installations will have to modulate their production. But the real lever is the electrification of uses," Bernard Fontana nonetheless insists. The EDF CEO welcomes "the publication of the PPE [Pluriannual Energy Plan]. The text confirms the objectives and provides visibility for industrial players."