The Bulgarian Nuclear Regulatory Agency (BNRA) has amended the licenses for the operation of Units 5 and 6 at the Kozloduy Nuclear Power Plant (NPP), as well as for the dry storage of spent nuclear fuel. The updated licenses are now permanent, reflecting changes in national legislation implemented earlier this year.
Under the Nuclear Energy Act, a periodic security review must be conducted at least every 10 years. NPP Kozloduy has committed to continuing the submission of summarized findings from these periodic reviews to BNRA for approval.
Unit 6, which underwent planned preventive maintenance starting on June 15, was reconnected to the national electricity grid on July 8. The maintenance was necessitated by faults in the oil system of a 24/400kV transformer, a non-nuclear component, and signs of a thermophore leak in a steam generator.
Unit 5, following its annual refurbishment, was reconnected to the national grid on June 10. The refurbishment included the installation of RWFA-type cartridges, manufactured by the US company Westinghouse, as part of the plant’s diversification program. This annual refurbishment involved replacing a quarter of the reactor cartridges, marking the beginning of a four-year transition to the new nuclear fuel.