Ukraine's Zaporizhzhya Nuclear Power Plant (ZNPP) has been relying on a single off-site power line for more than a week now after its only remaining back-up line was lost, once again highlighting an extremely fragile nuclear safety situation during the military conflict, Director General Rafael Mariano Grossi of the International Atomic Energy Agency (IAEA) said today.
Nuclear power plants (NPPs) need a secure supply of external electricity to cool their reactors and for other essential nuclear safety and security functions. However, this has been a major challenge over the past three years, with the ZNPP temporarily losing all off-site power eight times.
In the latest incident affecting the reliability of the supply of power from the grid, its sole 330 kilovolt (kV) back-up power line was disconnected on 11 February and has not yet been fully restored. This leaves Europe's largest NPP entirely dependent on its only remaining 750 kV line. Before the conflict, it had a total of 10 power lines - six 750 kV and four 330 kV - available.
"The Zaporizhzhya Nuclear Power Plant still needs reliable supplies of off-site power for cooling purposes, even though its six reactors have been shut down for more than two years now," Director General Grossi said. "The vulnerability of the external power situation remains a deep source of concern for nuclear safety."
The ZNPP said the 330 kV line was disconnected last week due to the activation of the electrical protection system. The Ukrainian regulatory body informed the IAEA that it was the result of unspecified military activity and that the power line had been damaged. The IAEA team at the ZNPP currently continues to gather further information regarding the status of the back-up power supply to the site.
Further underlining the constant risks to nuclear safety, the IAEA team based at the site heard an explosion close to the ZNPP on 12 February, coinciding with unconfirmed reports of a drone attack approximately 300 meters from the site. The team has over the past week continued to hear other daily explosions at varying distances from the ZNPP. No damage to the site has been reported.
The IAEA team continues to carry out walkdowns across the ZNPP as part of the work to monitor and assess nuclear safety and security.
The IAEA remains in contact with both sides regarding the next rotation of IAEA personnel at the ZNPP, after it was delayed last week due to intense military activity in the area.
At the Chornobyl NPP site, firefighters are continuing to put out small fires that keep smouldering and spreading on the roof of the New Safe Confinement (NSC), after it was struck on 14 February by a drone that pierced a hole in the large structure built to cover the reactor destroyed in the 1986 accident.
The IAEA team based at the site, which was granted unrestricted access to examine the impact of the explosion, conducts regular walkdowns and radiation measurements to independently monitor the situation. The team's measurements continue to show normal gamma radiation dose rate values near the NSC compared to those recorded by the IAEA since it established a continuous presence at the site just over two years ago.
The IAEA teams based at Ukraine's other NPPs - Khmelnytskyy, Rivne and South Ukraine - have continued to report frequent air raid alarms over the past week and were also informed of the presence of drones within the areas surrounding the respective sites.
