A gas-fired power plant in southern France was at risk of shutting down on Thursday as exceptionally high Mediterranean Sea temperatures restricted access to cooling water, adding pressure to the country’s electricity system already affected by reduced nuclear generation.
French utility EDF said the 930-megawatt Martigues gas plant could face an outage after seawater temperatures approached the temporary operating limit of 32 degrees Celsius. Authorities granted an exemption allowing the plant to continue operating above the standard 30-degree threshold until September 15.
The potential disruption comes as France grapples with significant nuclear power constraints, with 4.9 gigawatts of capacity unavailable due to high river temperatures and another 2.5 GW offline because of low river water levels.
Although gas-fired generation represents only a small share of France’s electricity mix, the loss of the Martigues plant would further tighten power supplies while nuclear energy, which provides around 70% of the country’s electricity, remains under pressure.
Climate experts said the country is experiencing an unprecedented combination of heat-related disruptions, affecting reactors that are not usually vulnerable to extreme weather conditions.EDF expects several nuclear reactors to continue reducing output on Friday due to high temperatures, although operations at the Bugey 3 reactor are expected to resume later in the day as cooler conditions return.
Meanwhile, the heat-related shutdown of the Golfech 2 reactor is expected to continue until July 25, while low water levels on the Meuse River have kept around 2.5 GW of capacity offline at the Chooz nuclear plant.
France’s weather agency, Météo-France, said temperatures should ease over the weekend, with the most intense heat largely confined to the southeast.
However, officials warned that persistent drought conditions, driven by weeks of extreme heat and limited rainfall since late May, continue to worsen and pose ongoing risks to the country’s energy infrastructure.
The developments highlight the growing impact of climate change on France’s power system, as prolonged heatwaves increasingly threaten both thermal and nuclear electricity production during peak summer demand.