EDF reports unplanned outage at Flamanville 1 French reactor

EDF reports unplanned outage at Flamanville 1 French reactor

EDF has announced an unplanned outage at the Flamanville 1 French reactor, located in the Manche department. The shutdown, which occurred between Friday and Saturday, was triggered by the reactor's protection mechanisms without causing an automatic shutdown of the reactor itself [2]. The reactor was disconnected from the power grid and subsequently reconnected on Saturday after necessary verifications were completed.

The Flamanville 1 reactor, part of EDF's nuclear fleet, was undergoing a gradual power increase phase following a two-month maintenance downtime. The unplanned shutdown, though brief, highlights the complexities involved in the reactor's startup process. EDF had previously indicated that the ramp-up phase would involve scheduled maintenance shutdowns and potential unplanned operations, with more than 1,500 safety criteria being tested during this initial startup phase [2].

The reactor was reconnected to the grid on Saturday, allowing the site's power ramp-up to continue. EDF emphasized that this temporary shutdown does not affect the production targets set for summer 2025. The company maintains its target timeline for full power output, aiming to reach 100% of nominal capacity by summer 2025 [2].

This unplanned outage is a reminder of the challenges faced by nuclear power plants, particularly during the startup phase. While it did not disrupt the overall production targets, it underscores the need for continuous monitoring and maintenance to ensure the safety and reliability of nuclear reactors.

References:
[1] https://energynews.pro/en/edf-anticipates-immediate-reduction-in-nuclear-output-amid-heatwave/
[2] https://energynews.pro/en/flamanvilles-epr-briefly-shut-down-before-resuming-power-ramp-up/
[3] https://www.bloomberg.com/news/articles/2025-06-24/edf-may-need-to-curb-french-nuclear-output-due-to-heat-wave
[4] https://energynews.pro/en/edf-delays-flamanville-epr-restart-for-the-fourth-time/
[5] https://www.home.saxo/content/articles/equities/the-case-for-a-nuclear-comeback-ai-policy-and-power-demand-04062025