On May 7, 2025, Zaporizhzhya nuclear power plant, Europe’s largest nuclear facility, suffered a loss of external energy supply. This crash cast a long shadow over the safety of its operations. The occurrence was the ninth total loss of off-site power since the Russian invasion of Ukraine began in February 2022. The continued turmoil poses significant dangers to Ukraine’s nuclear security. The plant has been in cold shutdown since 2024, amplifying these understandings.
Then, on July 4, 2025, the plant suffered a catastrophic failure. In doing so, it lost access to its primary 750kV high voltage power line, severely hampering operations. The loss caused the facility to switch to emergency diesel generators. They became dependent on them for over three and a half hours until the power was eventually restored. As noted repeatedly by the International Atomic Energy Agency (IAEA), maintaining external power is critical. This is especially critical as it relates to maintaining continuous cooling operations at the plant indefinitely.
Ongoing Power Challenges
Prior to the beginning of hostilities, Zaporizhzhya nuclear power plant was connected to ten off-site power lines. However, over the past several months, these resources have sharply decreased as continuing hostilities have destroyed critical infrastructure. Ukraine’s Energy Minister attributed Russian shelling for severing lines to one of the plant’s six reactors. This latest development makes the task of educating and healing all around the power supply all the more difficult.
Rafael Mariano Grossi, the Director General of the IAEA, highlighted his deep concern about the ongoing loss of power. He noted that it was almost unimaginable just a few decades ago for any large nuclear power plant to fail to maintain all its offsite power connections multiple times. Unfortunately, this has now become a regular occurrence at the Zaporizhzhya plant. Nearly three-and-a-half years since this catastrophic war began, the nuclear safety in Ukraine is still extremely perilous.”
Restoration Efforts
Upon the recent outage, Ukrenergo, Ukraine’s high-voltage line operator, rapidly surged their specialists. In a major achievement, they neutralized the risks of a security breach by restoring service at the Zaporizhzhya nuclear power plant. These initiatives are critical both in protecting the operational integrity of the system and keeping employees and traveling public safe with increasing threats.
Considering these recent episodes of power loss, it’s difficult to ignore the nuclear safety culture. These problems remain as conflict threatens to deepen further in the region. The situation remains precarious for both the plant and surrounding communities, emphasizing the need for ongoing monitoring and prompt action.
“Our team on the ground will continue to follow the situation very closely and report on further developments there.” – Rafael Mariano Grossi