IAEA warns of safety importance of substations

Director General Rafael Mariano Grossi, in his latest update, says that Ukraine's Khmelnitsky and Rivne nuclear power plants have been operating at reduced capacity after military action damaged an electrical substation.

The International Atomic Energy Agency (IAEA) said such substations "are indispensable for maintaining off-site power supplies that support safety systems and cooling functions, making their integrity vital for nuclear safety and security".

Grossi said: "Reliable off-site power is vital for the maintenance and operation of nuclear safety functions. To this end, Agency experts will, through dedicated expert missions, continue to assess the functionality of substations critical for nuclear safety and security."

Meanwhile, Zaporizhzhia Nuclear Power Plant, which has been under Russian military control since early March 2022, has had its main external power line shut since Friday after the activation of a protection system. The IAEA said the cause was still being investigated and they were "engaging with both sides to assist in the timely restoration of the line".

The loss of the 750 kV Dniprovska line means the plant is relying on its 330 kV backup Ferosplavna-1 line for external power at the moment. The plant recently went a month relying on emergency diesel generators for power, before IAEA-mediated local ceasefires allowed necessary repair work to take place to reconnect.

Meanwhile, Energoatom issued a statement explaining that Khmelnitsky unit 2 has "been operating with a damaged turbine since 2022 ...  currently, the power unit can produce up to 900 MW of electricity". The company added that it is in the process of purchasing a new, modernised rotor which "will not only restore the design nominal capacity, but also increase it by 40 MW to 1,040 MW".