Ukraine’s besieged nuclear plant loses its connection to outside power, renewing fears
By Marc Santora
Europe’s largest nuclear power plant was disconnected from the nation’s power grid after renewed shelling nearby Monday, according to Ukrainian energy officials, once again placing critical cooling systems at risk of relying solely on emergency backup power.
Herman Galushchenko, Ukraine’s energy minister, said a fire resulting from the shelling had severed the Zaporizhzhia plant’s last connection to a reserve line that had provided its only source of outside power.
Reactor No. 6, the only working reactor at the plant, was still producing power for the facility itself, and as of Monday evening, engineers had not switched on diesel generators, according to an official from Energoatom, the Ukrainian company responsible for operating the facility.
Galushchenko said it was yet another precarious moment made more threatening by the fact that firefighting crews had not been able to reach the site of the blaze.
“Any repairs to the lines are now impossible,” he said. “Fighting is taking place around the station.”
An International Atomic Energy Agency inspection team that had been at the plant left two monitors behind in the hopes that they could bear witness to events as they unfold and ease tensions at the facility, which is held by Russian forces but is still run by Ukrainian engineers. The larger hope had been that the shelling would stop.
The agency said that, according to Ukrainian officials, the reserve line had been “deliberately disconnected in order to extinguish a fire.”
“The line itself is not damaged, and it will be reconnected once the fire is extinguished,” said the agency, which is part of the United Nations.
Edwin Lyman, a nuclear power expert at the Union of Concerned Scientists, a private group in Cambridge, Massachusetts, said the current situation — in which the plant is relying on one of its own reactors to supply power to cooling systems — was “not unique, but it’s not standard practice.”
He noted that the International Atomic Energy Agency, which sets reactor safety standards for nuclear plants, published a technical document in 2018 that details the backup procedure.
“Some existing nuclear power plant technologies have this capability,” the IAEA document said, “while others do not.” Even plants that have the capability, it noted, may face “a time limit, generally of a few hours,” for the backup power.
Najmedin Meshkati, a professor of civil and environmental engineering at the University of Southern California, said the loss of off-site power — which has happened at the Zaporizhzhia plant at least twice in the past few weeks — was “one of the most dreadful events that could happen to a nuclear plant.”
Meshkati, who was a member of the committee appointed by the United States’ National Academy of Sciences to identify lessons from the disaster at the Fukushima nuclear power plant in Japan, said that it did not make sense for the reactor to be running.
An engineer in contact with people at the plant and in the satellite town of Enerhodar said Monday that her colleagues had reported severe shelling in the area over the past three days.
“Residential houses have been damaged, and there are many more people injured and killed than reported in the Ukrainian media,” said the engineer, who spoke on the condition of anonymity because she feared reprisals against her friends and family. “People continue leaving the town, including the plant’s employees.”
Ukrainian officials sought to keep up pressure on the International Atomic Energy Agency to offer a robust assessment of both the conditions at the plant and the challenges facing the Ukrainian engineers charged with its safe operation.
Repeated shelling over the past month has damaged all of the plant’s connections to four high-voltage external power lines, forcing it to use a lower-voltage reserve line to power the cooling equipment needed to prevent meltdowns. It was that reserve line that was cut off Monday.
When the main power lines and the reserve line were damaged by shelling and fires Aug. 25, a blackout at the plant forced it to rely on diesel generators to prevent a disaster.
Rafael Mariano Grossi, the director of the International Atomic Energy Agency, said at a news conference Friday that his biggest concern regarding the physical safety of the facility was related to a reliable connection to external power.