Electricity prices in France turn negative as renewable energy floods the grid

offshore wind turbines
An offshore wind farm in the Bay of Saint Brieuc, Brittany, France on April 11.
Matthieu Delaty—Hans Lucas/AFP/Getty Images

French electricity prices turned negative as a drop in demand and surging renewables output prompted some nuclear reactors to power down.

Daily consumption from Thursday through Sunday is seen falling by an average 6 gigawatts, a Bloomberg model shows. Sunny and blustery weather has driven up solar and wind generation, prompting the grid operator to request that Electricite de France SA take several nuclear plants offline.

While more clean power is needed across Europe to reach climate goals, soaring renewables output and a lack of battery storage mean reactors sometimes have to be turned off during periods of low demand. It’s becoming increasingly common around weekends in France — which gets about two-thirds of its electricity from its atomic fleet — and also occurs in the Nordic region and Spain.

EDF halted its Golfech 2, Cruas 2 and Tricastin 1 nuclear plants, and plans to halt three others during the weekend. Some renewables producers will also have to curb generation to avoid paying a fee amid negative prices.

French day-ahead power fell to -€5.76 a megawatt-hour, the lowest in four years, in an auction on Epex Spot. Germany’s equivalent contract dropped to €7.64.

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