Golfech

Golfech is a two-unit pressurised water reactor station operated by EDF on the Garonne river in Tarn-et-Garonne, south-west France. Its two REP 1300 reactors entered commercial operation in 1991 and 1993, providing a combined nameplate capacity of 2,620 MW (2 × 1,310 MW) under normal conditions. French environmental regulations set a river discharge temperature ceiling of 28°c on the Garonne; when cooling water approaches that limit, the plant must reduce or halt output regardless of reactor availability, making Golfech's contribution to French nuclear output hydrology-sensitive in summer.

Golfech is one of twelve two-unit French nuclear stations in the 1,300 MW series, France's most common reactor class. As part of the EDF-operated 56-reactor fleet, it normally contributes to France's structural role as continental Europe's largest nuclear exporter, suppressing French day-ahead power prices below German clearing levels.

Golfech Unit 2 shut at 23:45 on 22 June 2026 when Garonne cooling water neared the 28°c environmental ceiling during a record French heatwave, removing 1,310 MW from a nuclear fleet that had been holding the FR-DE day-ahead spread nearly EUR 17 below Germany. The curtailment compounded heat-driven cooling demand and contributed to German day-ahead clearing at EUR 207.84/MWh the following session, inverting the cheap-France trade. The episode is the second consecutive summer, after July 2025 forced at least 7 GW offline on the same constraint, that French nuclear curtailed on hydrology rather than planned outage. For energy desks, it re-rates river temperature as a recurring summer risk to the Continental power floor that sits alongside, and can arrive ahead of, the scheduled September Flamanville-3 overhaul.

Golfech was taken fully offline again on 12 July 2026, this time alongside Chooz and Bugey 3, as a second heat dome pushed the Garonne past its cooling-discharge ceiling for the second time this summer, weeks after the 22 June curtailment. The plant's contribution to French day-ahead pricing was again removed from the marginal stack rather than the price-setting nuclear baseload, and French power briefly cleared roughly EUR 7/MWh above Germany before settling back to a EUR 3/MWh France-cheaper gap by 13 July. Two curtailments in one summer, on top of the July 2025 precedent, reinforce that the Garonne's 28°c ceiling is a recurring structural constraint on the plant's output, not an isolated event.