Scheduled maintenance and new fuel: Unit 5 of Kozloduy NPP prepares

Planned maintenance and refueling of Unit 5 of Kozloduy NPP

On May 9, 2026, Unit 5 of the Kozloduy Nuclear Power Plant will be taken offline for scheduled annual maintenance and refueling with fresh nuclear fuel. Maintenance activities are expected to be completed by mid-June.

Bulgaria is the first country in the EU to successfully implement the diversification of nuclear fuel for VVER-1000 type reactors.

Diversification and safety

During this outage, RWFA-type fuel assemblies manufactured by Westinghouse will be loaded into the reactor for the third consecutive time. This is part of the large-scale program for a phased transition to new nuclear fuel, which began in the spring of 2024.

• Ensuring the safe operation of the nuclear power unit.
• Preventive maintenance of equipment.
• Confirmation of the successful implementation of the energy strategy.

The successful transition was also reported during the Tenth Review Meeting of the Convention on Nuclear Safety in Vienna. The Nuclear Regulatory Agency confirms that all processes are running smoothly and in full compliance with the issued permits.