French Nuclear Outages Caused by Jellyfish Are Being Extended
(Bloomberg) -- Electricite de France SA said two reactors which were taken offline due to jellyfish clogging up a pump would be out of service for longer than initially planned.
The Gravelines site on the north coast of France was affected by an unforeseen swarm of jellyfish clogging up filter drums, which are part of the cooling system. Gravelines 3 is now set to return Sunday and Gravelines 4 on Friday — both two days later than previously expected, according to a notice from EDF.

The outage — which EDF said could be extended further — is adding pressure on Europe’s power grid just as a heat wave drives up demand for cooling. EDF is also curbing output at another reactor near Lyon, with high Rhone river temperatures making it difficult to cool the facility.
French day-ahead prices rose 21% to €96.56 per megawatt-hour on Epex Spot, the highest since June 30.
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