UKRAINIAN SOLUTIONS FOR SAFE NUCLEAR POWER PLANT OPERATION PRESENTED AT INTERNATIONAL CONFERENCE IN BULGARIA

On September 14–19, 2025, the 1st International Conference on Fuel Characteristics for Light Water Reactors, Modeling, and Experimental Support was held in Nessebar, Bulgaria. The event, organized by the Institute for Nuclear Research and Nuclear Energy of the Bulgarian Academy of Sciences with the support of Framatome, Westinghouse, Studsvik, and Kozloduy NPP, brought together leading nuclear experts from around the world — scientists, nuclear fuel manufacturers, regulators, and representatives of NPP operators.

Energy Safety Group, JSC «NNEGC «Energoatom», STC «E.O. Paton Electric Welding Institute» and NFC STE NSC KIPT represented Ukraine at the forum. Oleksandr Mazurok, General Director of ES Group LLC (part of the group of companies Energy Safety Group), gave a presentation entitled «Approaches to supply Ukrainian NPPs with core components». He showcased that the country has already established and successfully executed solutions in the field of diversifying the supply of key elements of reactor core components.

The development, production, and operation of alternative components for VVER reactors, such as control and protection system absorber rods (RCCA) for VVER-1000 reactors, superstructures and shielding cassettes for VVER-440 reactors, is carried out by Ukrainian enterprises and scientific institutes in cooperation with NNEGC «Energoatom». The extended service life of the RCCA in operational settings has been validated. Energy Safety Group is acting as an engineering partner in this process, offering comprehensive support to ensure successful licensing and implementation during trial operations.

As part of the program, the service life of most RCCA kits for VVER-1000 reactors was extended from three to five years for the control group and from ten to fifteen years for the emergency protection groups. Individual resource assessments were conducted for separate sets, confirming their full compliance with safety criteria. This allowed for the continuous operation of the power unit and the transition to the implementation of the new Ukrainian-designed RCCA.

All necessary justifications and assessments have been approved by the nuclear regulator, and pilot operations of domestic manufactured components are currently underway at the VVER-1000 power units. Testing of similar solutions for the VVER-440 will commence in the near future.

«This exemplifies effective technical cooperation between industry and science, demonstrating its reliability in practical operating conditions,» says Oleksandr Mazurok. «Ukraine has acquired unique experience that can be utilized by European NPPs operating VVER reactors. This experience can help them diversify their main components and reduce their dependence on russia.»

The Energy Safety Group’s participation in the conference, which brought together representatives from Westinghouse Electric, Framatome, Kozloduy NPP, Studsvik, INRNE-BAS, and other leading organizations in the industry, showcased the strong integration of Ukrainian experts into the global professional community. This event provided an opportunity for partners and colleagues to familiarize themselves with our practical experience in aging management, safety assessment, and the diversification of VVER components. These topics are particularly relevant amid the ongoing transformation of the European nuclear market.