Backup power supply ensured at Russia-occupied Zaporizhzhia NPP - IAEA

The Zaporizhzhia nuclear power plant specialists took measures to ensure the supply of backup power in the event of the breach at the main external power line, as happened repeatedly since the full-scale invasion.

This was stated by IAEA Director General Rafael Mariano Grossi, Ukrinform reports.

After the shutdown of the only 750 kV line remaining at the ZNPP, the plant can still have access ti electricity from outside its perimeter through a backup 330 kV line, as long as it remains connected to the power grid. However, from mid-2023, the line requires manual intervention to operate.

Work was carried out on backup electrical transformers. Two of the three such transformers are now operational, and one of these two is permanently connected to the on-site backup power lines of all six units.

“This means that if the main power supply through the 750 kV switchyard is lost, the back-up line will automatically be able to provide electricity to the plant without manual, and hence delayed, intervention, provided it remains operational,” Grossi said.

Five of the six reactors at the ZNPP remain in cold shutdown, and power unit 4 is in hot shutdown to produce steam and heat, including for the nearby town of Enerhodar, where most of the plant staff live.

It is noted that IAEA experts remain unable to gain access to all parts of the site, and for the past two weeks they have not been allowed to access the reactor halls of units 1, 2 and 6,  where the reactor core and spent fuel are located.

In addition, the invaders restrict IAEA's access to some parts of the ZNPP turbine halls, in particular to those areas of reactor units 3, 4, and 6. IAEA experts still await the access to the reactor rooftops planned on December 19 that did not happen due to the invaders citing "security concerns".

During a walkdown of the safety system rooms of unit 6 on 22 December, the IAEA experts observed boric acid deposits on valves, a pump and on the floors of several rooms in the containment building. The plant informed the team that the source of the leak is one of the boric acid storage tanks and that considering the small magnitude of the leak it is not planned to be repaired immediately, but rather as part of the planned maintenance of the impacted system.

As Ukrinform reported earlier, the Russian occupation administration at the Zaporizhzhia NPP continues to prevent IAEA experts from gaining full access to the plant’s premises.