Ukraine’s Zaporizhzhya Nuclear Power Plant (ZNPP) has again lost all access to external electricity following shelling overnight and it is now receiving back-up power from its emergency diesel generators, further underlining the extremely precarious nuclear safety and security situation at the facility and the urgent need to establish a protection zone around it, Director General Rafael Mariano Grossi said.
The plant’s diesel generators started operating automatically after the plant’s connection was cut both to its main 750 kilovolt (kV) power line and to its back-up off-site power supplies from a 330 kV line that provides electricity through the switchyard of the nearby thermal power station.
The 750 kV line was disconnected following shelling at around 10pm local time yesterday, and the 330 kV line shortly after midnight, Director General Grossi said, citing information he had received from the team of IAEA experts at the site.
Senior Ukrainian operating staff informed the IAEA experts that there were indications that the power lines had sustained physical damage at two different locations about 50-60 kilometres from the plant itself, in Ukrainian-controlled territory. Repair work at one of the locations, where the 330 kV line was damaged, is under way.
The ZNPP, Europe’s largest nuclear power plant, has lost external power also previously during the current conflict in Ukraine, forcing it to rely on the diesel generators until off-site electricity became available again.
The plant has fuel for around 15 days of diesel generator operations, according to Ukraine’s national nuclear operator Energoatom. Currently, nine of the plant’s 20 diesel generators are operating to provide the power the plant needs for reactor cooling and other essential nuclear safety and security functions.
Following the loss of external power, the two reactors that were in hot shutdown mode to provide steam to the plant’s operations are being transferred to cold shutdown. The four other reactors were already in cold shutdown.
“This is an extremely concerning development that again demonstrates the plant’s fragile and vulnerable situation,” Director General Grossi said. “Despite the best efforts of the plant’s courageous staff to stabilize the external power situation in recent weeks, the Zaporizhzhya Nuclear Power Plant has again lost all access to off-site electricity. For now, it receives the power it needs from the on-site diesel generators. But this is clearly not a sustainable way to operate a major nuclear facility. Measures are needed to prevent a nuclear accident at the site. The establishment of a nuclear safety and security protection zone is urgently needed,” he said.
To help achieve this vital objective, Director General Grossi has engaged in high-level talks with both Ukraine and Russia in recent weeks aimed at agreeing and implementing such a zone around the ZNPP as soon as possible.