Why France's Power Prices Tumbled To Zero Despite Winter Onset

France’s electricity prices plunged to zero for several hours in the day-ahead market, allowing consumers to access free power during that period, according to Epex Spot data.

The rare price collapse was driven by a combination of factors — an unusually mild winter that slashed heating demand and a surge in renewable generation, which flooded the grid with excess supply.

Peak power demand on Dec. 9 dropped to 62 gigawatts from 69 gigawatts a week earlier, according to grid data cited by Bloomberg. Jet streams pumped warm air into northern France, pushing temperatures up to 13°C above seasonal norms and boosting wind farm output.

At the same time, France’s extensive nuclear fleet was operating at 86% capacity, adding to the supply glut.

According to the Paris-based International Energy Agency, renewable energy development across the globe will induce a fall in coal-generated power next year.

"The rapid growth of renewables, supported by rising nuclear generation, is set to displace global coal-fired generation, which is forecast to fall by an average of 1.7% annually through 2026," the organisation said in its Executive Summary for global electricity demand.

France is reportedly facing an oversupply of electricity with the glut expected to last until 2028, according to Bloomberg. Power exports could surpass last year’s record, while domestic consumption remains subdued and solar and wind output continues to expand.

French next-year electricity contracts also decreased by around 30% in 2025 to trade close to 50 euros per megawatt-hour, the report added. This was a level that was last seen five years ago in 2020.