Jellyfish Again Disrupt Output at French Nuclear Site This Month
(Bloomberg) -- A swarm of jellyfish forced Electricite de France SA to reduce output at its Gravelines nuclear power plant, adding to supply concerns that are pushing French power prices higher.
The jellyfish, which forced some reactors to shut down at the site earlier this month, have now affected at least three reactors, while workers are due to strike from Friday at the separate Chinon nuclear plant. The disruptions are adding to uncertainty over nuclear power availability and this week helped push French month-ahead contracts to their highest level since January last year.
France’s electricity market is particularly sensitive to changes in atomic output because its 57 reactors generate most of the country’s power, while neighboring nations also rely on its exports. The fleet has faced significant disruption this summer with heat waves forcing EDF to curb production at some plants that use river water for cooling.
While temperatures across France have eased following a series of extreme heat waves, unusually warm conditions are lingering in surrounding waters. Elevated marine temperatures can cause jellyfish populations to bloom. Coastal nuclear plants such as Gravelines rely on seawater for cooling, leaving their pumping systems vulnerable to swarms of marine life.
The latest disruption began on Wednesday, adding to existing outages for maintenance and repairs at Gravelines. Four out of the six 900-megawatt reactors were fully offline, while output at two units were reduced as of 1 p.m. Thursday, according to grid data. Gravelines, on France’s northern coast, faced similar problems last year when swarms of jellyfish clogged its filter drums.
The disruption highlights climate change challenges faced by energy producers such as EDF. The state-owned utility earlier this year signed an accord with fishermen for tracking jellyfish swarms and taking them away when they approach sea water intakes of reactors.
This comes as Europe’s weather has broken a long sunny and warm spell with more covered and cooler conditions. Solar output has suffered, with output around midday in France on Thursday around a third lower than it was at the same time just two weeks ago according to data from RTE.
(Updates with solar drop in final paragraph.)
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