Tonight, a complete blackout occurred at the Zaporizhzhia Nuclear Power Plant.
On the evening of December 1, there was a break in the power line 'Zaporizhzhia TPP – Ferroalloy Plant' with a voltage of 330 kV, through which the station received power from the Ukrainian power system.
At 02:31 during the air raid alert, the last line 'Zaporizhzhia NPP – Dniprovska' with a voltage of 750 kV was de-energized.
Due to the complete blackout, ZNPP switched to supplying its own needs from diesel generators. All 20 diesel generators were automatically activated, 8 of which were later left in operation.
The greatest threat to safety in such a condition exists at Unit 4. It is caused by the fact that the occupiers used it in violation of the conditions of the license for the operation of the NPP reactor units of the Ukrainian regulator and kept it in a hot state. De-energizing the main circulation pumps that cool the active zone leads to the reactor unit transitioning to natural circulation mode. Such a mode is challenging for the reactor unit; its duration is limited by the project, and it can lead to the failure of the main equipment of the power unit. The unit requires urgent transition to a cold state.
Through the efforts of Ukrainian specialists, on December 2 at 7:00 in the morning, communication with the Ukrainian power system was restored, namely, the operation of the power line with a voltage of 750 kV was resumed.
This is already the eighth blackout that occurred at ZNPP and could have led to a nuclear catastrophe.
