Russia's massive attack on Ukraine's energy infrastructure on Thursday, October 30, damaged substations that are critical to nuclear safety, the International Atomic Energy Agency said. According to the IAEA, the Yuzhnoukrainska and Khmelnytskyi nuclear power plants lost access to one of their external power transmission lines, while the Rivne nuclear power plant was forced to reduce the capacity of two units at the request of the network operator. IAEA Director General Rafael Grossi warned that the nuclear threat was real and called for maximum military restraint near nuclear facilities.
Russia launched a combined strike on Ukraine's energy infrastructure, including substations, on October 30. The International Atomic Energy Agency (IAEA) said that substations critical to nuclear safety and security were damaged.
The IAEA reported that following the attack, its inspection teams at the Yuzhnoukrainska NPP and Khmelnytskyi NPP recorded the loss of access by each station to one of its external power lines. External lines are the power supply channels that power the safety systems of the stations in the event of any emergency. In normal operation, a nuclear plant not only generates energy, but also depends on a stable external power supply to cool the reactors and nuclear fuel. The loss of such lines makes the system more vulnerable.
Separately, the IAEA team at the Rivne NPP reported that the plant was forced to reduce the capacity of two of its four power units at the request of the power system operator. This is done to stabilize the network in conditions of shortage or imbalance after massive shelling. That is, the attack hit not only thermal and hydroelectric power generation, but also directly affected the nuclear segment, which remains a key source of electricity in Ukraine.
IAEA Director General Rafael Grossi stated that “the nuclear threat is real” and again called for maximum military restraint in areas where nuclear facilities are located and for adherence to the “seven indispensable principles of nuclear safety and security.” According to the IAEA, any strikes that could affect the external power supply of nuclear plants automatically pose a risk to their stable operation.
This is not just about local power outages for consumers. It is a strategic risk for the country's entire nuclear security system.
Nuclear and radiation safety experts have already warned that Russia’s deliberate strikes on critical power substations are not just an attempt to leave cities without electricity, but also a way to exert pressure through the threat of a large-scale blackout that could paralyze the normal power supply of nuclear plants. Radiation safety researcher and Greenpeace nuclear energy specialist Jan Vande Putte stressed that strikes on key substations could lead to a complete loss of external power to operating nuclear plants. In such a case, the country risks a real technical blackout, when the reactors will have to be transferred to emergency diesel generators, which is already a scenario with the risk of a nuclear accident.
Greenpeace and energy analysts describe this scenario as one of the most dangerous for Ukraine since the start of the full-scale invasion. They emphasize that if the nuclear power plant loses external power, the cooling systems of the reactor and spent nuclear fuel switch to diesel generators and batteries. This is a “last line of defense” designed for a limited time. If the network damage cannot be quickly restored or fuel delivered, there is a risk of overheating and damage to the nuclear fuel, which in an extreme case could mean the release of radioactive substances far beyond the borders of Ukraine. Greenpeace compares these risks to Fukushima in 2011 or even Chernobyl, emphasizing that Russia is actually using nuclear safety as a tool of blackmail.
The Ukrainian Ministry of Energy officially warned back in 2024 that Russia was preparing strikes specifically on critical substations that provide reliable power to nuclear power plants. The logic of these attacks is simple: to strike not only at generation, but at the "nerves of the system" - the nodal substations through which nuclear power plants receive stable power for their safety systems and transmit electricity to the general grid. Such facilities are difficult to quickly restore, and each damage accumulates a risk for the entire energy system. This makes strikes on the energy sector not just a war crime against civilian infrastructure, but a direct threat to nuclear safety in the center of Europe.
Against the backdrop of these events, the IAEA has consistently warned that the nuclear security situation in Ukraine is not abstract; it remains critically fragile. The organization has repeatedly recorded drone explosions near the Yuzhno-Ukrainian nuclear power plant (less than a kilometer from the plant’s perimeter) and record-breaking outages at the Zaporizhzhia nuclear power plant, which was captured by the Russians and where units had to be switched to emergency diesel engines. Each such incident is another reminder that Russia’s new energy tactics directly affect nuclear security and could have consequences not only for Ukraine but also for neighboring countries.
