EDF pulls 3 GW of French nuclear output as 42C heat forces river curbs
State utility to disconnect Golfech 2 reactor at noon Wednesday, tripling morning curtailments to 4.6% of France's nuclear fleet.
EDF will cut 3 GW of nuclear output from 12:00 CET on Wednesday (2026-07-08), equal to 4.6% of France's total installed capacity, as temperatures reach 42C across the country, according to Remit data published by Montel. The utility plans to disconnect the 1.3 GW Golfech 2 reactor on the Garonne River in southwestern France at noon, adding to 1.6 GW of cuts already imposed at 09:00 CET.6
The move underscores France's persistent summer vulnerability. Nuclear plants discharge heated water into rivers and are restricted when ambient water temperatures or flow rates breach environmental thresholds. Golfech, located on the Garonne, is one of four riverside sites subject to seasonal curbs.6
The timing complicates EDF's demand-growth plans. The state utility on Wednesday (2026-05-20) announced plans to raise power demand by 5.5 TWh, or 1% annually, calling electrification "imperative" following the energy shock from the Iran conflict. EDF said new heat pumps and electric trucks could add 0.5 TWh a year, while offering "turnkey sites" with grid connections to attract industrial load.2
But delivering on that growth requires baseload availability. Wednesday's (2026-07-08) 3 GW cut is three times the scale of the morning reduction and signals the fleet is already stretched by early July heat. The Golfech 2 offline notice came with less than three hours' warning.6
Meteorologists in April had flagged frequent summer rainfall that might limit nuclear disruption. That forecast has not held. June turned sunnier and warmer than expected, and the first week of July brought the kind of sustained heat that forces operational trade-offs between generation and river ecology.4
France generates roughly 70% of its electricity from nuclear. A 3 GW reduction tightens the supply cushion and raises the probability of imports from Germany and Spain during peak afternoon demand. ICE Endex TTF front-month gas settled at €49.12 on Wednesday (2026-07-08), down 0.32%.6 [LIVE PRICES]
European gas demand has fallen about 10% this year compared with prior periods, helped by industrial curtailment and mild weather earlier in the season. France capped household gas prices at last year's level and power tariffs 4% higher, with 2023 caps planned at a 15% increase. Those retail interventions cushion consumer bills but do little to insulate the grid from weather-driven supply swings.3
EDF's renewable division has separately moved to curtail subsidised solar and wind output during negative price periods starting the week of Monday (2026-05-25). The measure affects 842 MW of capacity under feed-in tariffs and aims to reduce the financial burden of must-run renewables when the grid is oversupplied.1
The utility has posted strong operational and financial performance in recent quarters, including positive cash flow and reduced net debt in its 2025 annual results.5
Watch whether EDF extends curbs beyond Wednesday (2026-07-08) if the heatwave persists through the week. A prolonged reduction would force France to lean harder on imports and raise the risk of afternoon price spikes, with potential knock-on effects for cross-border flows and regional baseload pricing.6