Ukraine's energy system in worst state since September 2024 - IAEA
Kyiv • UNN
IAEA head Rafael Grossi stated that the situation in Ukraine's energy system is the worst since September 2024, when substation monitoring began. Constant instability in the power grid undermines nuclear safety, and the Zaporizhzhia Nuclear Power Plant has lost external power supply 12 times.
The situation in the energy system is currently in the worst state since September 2024, when the International Atomic Energy Agency (IAEA) began monitoring substations critical to nuclear safety and security in Ukraine. This was stated by the head of the agency, Rafael Grossi, reports UNN.
The attacks on Ukraine's power grid appear to be coordinated for maximum disruption, and their frequency and scale underscore that the overall stability of the grid is deteriorating, not improving.
He again called for maximum military restraint.
No one wants a nuclear accident and no one benefits from it.
He emphasized that the latest mission, conducted from December 1 to December 12, 2025, included visits to more than ten substations – critical for ensuring nuclear safety by providing nuclear power plants with the electricity needed to cool the reactor and other safety systems.
The mission's goal was to assess the damage, review repair work, and identify practical steps to enhance the resilience of external power sources for the country's nuclear power plants.
The IAEA Director General stated that nuclear safety at the three operating nuclear power plants in the territory controlled by Ukraine remains under pressure due to ongoing military activities and related damage to energy transmission infrastructure.
Over the past weekend, power grid outages caused power fluctuations and temporary disconnections of power lines at the Khmelnytskyi, Rivne, and South Ukrainian NPPs, he noted. According to him, in several cases, units operated at reduced power to maintain grid stability and prevent equipment damage.
The constant instability in Ukraine's power grid continues to undermine nuclear safety. Although backup systems have functioned properly, repeated losses of external power and limited redundancy increase the risk and reinforce the need for reliable external power supply.
The IAEA team also confirmed that continuous and deliberate attacks on critical grid infrastructure have had a cumulative impact on NPP operations and personnel working conditions. Power outages affect the cities where station personnel live, worsening living conditions and directly impacting personnel through disruptions to electricity, heating, and water supply.
In addition, it is noted that the Russian-occupied Zaporizhzhia Nuclear Power Plant (ZNPP) of Ukraine temporarily lost external power supply for the 12th time since the beginning of the full-scale aggression early in the morning of December 13, as both the main 750 kV Dniprovska power transmission line and the backup 330 kV Ferroalloy-1 power transmission line were disconnected. All available emergency diesel generators automatically started, ensuring continuous cooling and other important safety functions. Both external power lines supplying the NPP – the largest in Europe – have since been reconnected, and the diesel generators have been returned to standby mode, the agency clarified.
It also reported that on December 15, despite the ZNPP retaining access to the two remaining external power lines, another incident highlighted the fragile nuclear safety situation at the plant. Power transmission between the ZNPP switchyard and the Zaporizhzhia Thermal Power Plant (ZTPP) switchyard via an autotransformer became unavailable, significantly reducing the flexibility and resilience of the facility's electrical configuration. Following an investigation conducted by the ZNPP, damage was found to the power line between the autotransformer and the ZTPP switchyard, which was reportedly caused by military activity.
The ZNPP informed the IAEA team at the plant that access to the affected area could not be granted for safety reasons. As of today, the ZNPP is still exploring ways to repair the line.