Unit 5 of the Kozloduy Nuclear Power Plant is scheduled to be taken offline on May 9 for its planned annual maintenance and refuelling, including the loading of American nuclear fuel, according to information presented in the annual report of the Nuclear Regulatory Agency (NRA).
The outage is expected to continue until mid-June, when new fuel assemblies produced by Westinghouse are set to be installed. The process is part of a gradual transition away from Russian fuel, which began in 2024 and is planned to continue over four years.
Authorities confirm that until 2027 the reactor core of Unit 5 should be fully loaded with US-produced fuel. For nearly two years, the unit has been operating with a mixed core containing both Russian and American fuel assemblies as part of the transition phase.
The head of the Nuclear Regulatory Agency, Tsonko Bachiyski, said the licensing process for the new fuel had been successfully completed, allowing Bulgaria to move ahead with diversification ahead of most EU countries.
“Thanks to the good organisation of the licensing process for the new nuclear fuel for Unit 5 of Kozloduy NPP, we are the first country in the European Union to have licensed or authorised a new type of fuel different from the original,” Bachiyski stated.
He added that monitoring systems currently showed stable reactor conditions and no technical problems with the fuel in use. Previous inspections during maintenance outages have not identified deformation or defects in the fuel assemblies.
“All systems monitoring the condition of the reactor core show that there are no issues with the fuel,” he said, noting that the situation would be assessed again after the upcoming shutdown and inspection period.
The NRA also confirmed that the transition process is progressing as planned, with full conversion to Westinghouse fuel expected until 2027. A final assessment of long-term performance is expected in 2028, when it will become clear whether the new fuel will remain in permanent use.
“In 2027, the fifth unit will be fully loaded with Westinghouse fuel, and in 2028 it will become clear whether this fuel will remain,” Bachiyski said.
Officials also noted that due to Russia’s war in Ukraine, Bulgaria had not exported spent nuclear fuel for several years, adding another layer of complexity to nuclear fuel management during the transition period. (Novinite)