Aug. 11 is quickly becoming jellyfish invasion day at the Gravelines nuclear power plant in northern France.

Despite spending hundreds of thousands of euros to protect the plant from a jellyfish swarm like the one that saw reactors shuttered on Aug. 11, 2025, French utility provider EDF on Tuesday was again forced to bring the parts of the facility offline due to the presence of “several dozen tons” of jellyfish blocking pumping systems.

“On-site teams are fully mobilized to ensure the safety of the facilities and to reconnect the reactors to the national power grid,” EDF said in a statement.

Three fishing vessels are now “constantly patrolling off the coast of the plant” to conduct “preventive fishing operations […] 24/7,” the company added.

Tuesday’s jellyfish invasion comes a the latest in a series of climate change-driven incidents that have affected French nuclear energy during a particularly infernal summer.

Nuclear power plants are typically built by rivers or on coastlines so they can use nearby water sources to cool their reactors. But a record number in France this summer have been forced to temporarily shut down due to heatwaves and droughts affecting their water supply.

Rising sea temperatures have made jellyfish swarms more common along the French coast in recent years, and those swarms can affect a plant’s ability to bring in seawater — which is what happened at Gravelines. Following last year’s incident at the plant along the North Sea, EDF installed cameras and deployed fishing boats to monitor the situation.

While the vessels “prevented a massive influx of jellyfish” on Saturday and Sunday, they were eventually overwhelmed as the swarm grew from “about 100 kilograms” to “several dozen tons,” the French state-owned utility giant said.

Opponents of nuclear energy were quick to jump on the incident.

“This only highlights that nuclear power plants are ill-equipped to deal with the consequences of climate change,” the French branch of Greenpeace said in statement.

ATHENS — Sparks from Greece’s aging electricity grid are responsible for a disproportionate share of the country’s most destructive wildfires, according to preliminary data from Greece’s Arson Crimes Investigation Directorate and evidence from recent fire investigations. 

While power infrastructure accounts for only a small share of wildfire incidents, fires sparked by the grid often break out under the most dangerous conditions — during high winds, in periods of heavy electricity demand and often in remote, fire-prone areas — making them more likely to spread rapidly and become catastrophic. 

According to the Arson Crimes unit, fires linked to the electricity grid account for about 75 percent of the land burned in Greece this year.

Two deadly wildfires in late July — one in western Attica and one on the island of Crete —were also linked to the electricity grid in preliminary findings from the Greek fire brigade. The fires destroyed more than 36,000 acres and killed four people. 

“Six out of 10 major fires and 55 percent of the area burnt in 2025 were caused by the power grid,” said Elias Tziritis, wildfires actions coordinator at World Wildlife Fund Greece. “Statistically speaking, the majority of fires may not start from the power grid, but these are the ones that cause the most major, devastating fires.”

Loose or sagging power lines, vegetation coming in contact with cables, dust buildup on transmission equipment and other such faults can all generate sparks. The risk rises during strong winds and periods of heavy electricity demand, when aging infrastructure is under greater strain. 

Much of Greece’s electricity grid was installed decades ago and runs above ground through fire-prone forests and increasingly depopulated rural areas. In the 1960s, the country opted for an overhead network as a cheaper way to extend electricity across the country, while the prolonged financial crisis that began in 2009 further constrained investment in the system.

Critics say Greece has moved too slowly to bury distribution lines and adapt the network to increasingly severe fire conditions.

“We raised the issue years ago, calling for something to be done with the power grid urgently,” said Christos Kalogeropoulos, a retired lieutenant-general with the Fire Service and former director of the Arson Crimes unit. “We have been calling for urgent underground cabling.”

Greece’s power distribution operator HEDNO disputes suggestions that the network is a major cause of wildfires, saying only about 1 percent of wildfire incidents recorded in 2025 were attributed to the electricity grid, compared with roughly 3 percent in the U.S. The company also said its crews have been deployed to major fire fronts to support emergency services and restore electricity to affected communities. 

“The easy targeting of HEDNO whenever a fire breaks out serves neither the truth nor the protection of the public but creates false impressions, and, in many cases, appears to serve short-term expediencies and self-serving agendas by covering up local responsibilities,” said the company in a statement.

Following the fire in Crete, authorities arrested two HEDNO network operations and maintenance managers, who were later released. In Viotia, where a late-July fire spread into western Attica, investigators suspect sparks came from equipment on a private wind farm. A local mayor, a contractor and a company owner were taken into custody last week.

Energy Minister Stavros Papastavrou said the government plans to tighten rules governing private power projects. But experts warn that focusing on private operators risks obscuring the broader problem of an aging public grid. 

Moving cables underground is expensive and time-consuming, said Paleologos Paleologou, associate professor of forest protection at the Agricultural University of Athens. 

Paleologou said researchers need access to detailed data on the location of power lines and pylons to model where the network is most vulnerable. “If we had that information, we could tell them where their network is vulnerable and where a fire could break out,” he said. “Since the budget is limited, we should prioritize the most difficult areas.”

The government is currently using money from the EU Recovery and Resilience Facility to fund underground cabling. It says the share of the distribution network that is underground has risen to about 14 percent, up from 9 percent in 2021. 

Alexandra Sdoukou, a spokesperson for the ruling New Democracy party, said burying the entire 120,000-kilometer medium-voltage network would cost about €35 billion, requiring the government to first focus on areas under the greatest risk. 

Greece’s Energy Ministry did not reply to a request for comment.

Meanwhile, opposition parties and advocacy groups accuse the government of moving too slowly, failing to maintain the grid properly and dropping some fire-prevention projects from EU recovery funding.

“There is still no public acknowledgement of the problem,” said Tziritis. “The issue should be recognized and efforts to find solutions should be taken at the government level.”

Such an acknowledgement could also carry legal and financial consequences. California utility Pacific Gas & Electric filed for bankruptcy after its equipment sparked catastrophic wildfires and exposed the company to billions of dollars in liabilities.

In Greece, the number of court cases involving fires linked to the electricity grid rose from 369 to 681 in 2024, said Kalogeropoulos.

One of the few cases to result in a final ruling against HEDNO is a class action lawsuit following a 2015 wildfire in Neapoli, Laconia, which destroyed homes and large areas of woodland and farmland. Around 90 victims are now pursuing compensation. 

“It is a real struggle for a citizen to go after an electricity grid company,” said Evgenia Lazaraki, a lawyer representing the victims. Utilities, she said, have both the technical expertise and access to evidence needed to defend themselves, putting plaintiffs at a significant disadvantage.