The Ukrainian nuclear agency Energoatom reported on Aug. 10 that the Russian-occupied Zaporizhzhia Nuclear Power Plant lost power from the main 750 kilovolt (kV) power line overnight.
The plant was then connected to the 330 kV backup line instead. The risk of this backup power line failing puts the largest nuclear plant in Europe on the verge of a blackout.
The main danger of losing external power is that the 4th reactor would go into "hot shutdown" as a result of the cooling pumps being switched off, Energoatom explained.
Without sufficient cooling, the equipment within the reactor can fail, heightening the risk of a nuclear accident.
Energoatom emphasized that the continued occupation of the plant by "illegitimate and untrained" management is bringing it "closer to disaster."
Russian forces have occupied the Zaporizhzhia plant since March 2022. Throughout the all-out war, the plant has been repeatedly disconnected from the Ukrainian power grid due to Russian attacks on the country's energy infrastructure.
For four months between March and July 2023, the plant was disconnected from the 330 kV backup power line due to damage on the opposite bank of the Dnipro River.
In October 2022, the plant was forced to rely on diesel generators to provide power to the cooling systems due to Russian shelling.
Before Russia's full-scale war, the nuclear plant had six backup lines and four main lines of 750 kV.
After nearly a year and a half of Russian occupation, uncertainty about what Russia could do next at the plant remains.
Ukraine raised fresh concerns of a potential accident at the plant in June, with top officials warning that Russia had rigged the plant with explosives and could launch a terrorist attack.
Since occupying the plant, Russia has used the nuclear plant as a military base, placing troops and equipment there.
The International Atomic Energy Agency has staff based at the plant on rotation since September 2022 to monitor the situation.