The agency said diesel generators started operating automatically when connections were cut to a main 750 kilovolt (kV) power line and a backup 330 kV line which provided electricity through the switchyard of a nearby thermal power station.
The 750 kV line was disconnected following shelling at around 22:00 local time yesterday, and the 330 kV line shortly after midnight, IAEA director-general Rafael Grossi said.
Over the course of October, Zaporizhzhia’s connection to the 750 kV line was cut three times in ten days, the IAEA said earlier. On Monday the station had just one of four power lines remaining in use, signifying the vulnerability of the facility.
The IAEA said today that the power lines received damage about 50-60 km from the Zaporizhzhia station, in Ukraine-controlled territory, and repair work at the location of 330 kV line are under way.
Ukrainian nuclear operator Energoatom said that backup generators at Zaporizhzhia have enough fuel to operate for 15 days in a full blackout mode, while the IAEA said presently nine of the plant’s 20 diesel generators are operating to provide the electricity needed for reactor cooling and other essential nuclear safety and security functions.
Energoatom made allegations on Telegram that cutting off external power to Zaporizhzhia from the Ukrainian grid represents an attempt by Russia to later connect the plant to the grid of territories under its actual control. Russia has not commented.
The IAEA repeated its calls for the establishment of a protection zone around the Zaporizhzhia station stressing the “extremely precarious” nuclear safety and security situation at the facility.
Of the station’s six reactor units at Zaporizhzhia, Units 5 and 6 are being transferred to cold shutdown mode as a result of the power loss. The remaining four units remain in cold shutdown.
Units 5 and 6 were not generating electricity at the start of the week, but were kept in hot shutdown to produce steam needed for the plant’s operations.
