Rosatom’s fuel company TVEL said on 24 May that it had completed development of a new modification of nuclear fuel for VVER-440 reactors at Finland’s Loviisa NPP. The modification of the VVER-440 fuel cartridge with an increased uranium capacity will increase the efficiency of fuel during operation and the operation of the NPP in general, Rosatom said. By increasing the mass of uranium in one fuel element, the level of uranium-235 enrichment will be reduced without reducing the generation of thermal energy in the reactor. The lower level of uranium enrichment will, in turn, reduce the cost of the fuel production chain, and optimise the handling of irradiated fuel.
Alexander Ugryumov, Vice President for Scientific and Technical Activities and Quality at TVEL, said based on the new design TVEL has developed two different VVER-440 fuel cycle management strategy solutions for our Hungarian and Finnish customers, tailored to their individual requirements. “While the Hungarian Paks NPP sees an economic effect in reducing the number of fuel assemblies loaded into the reactor, the Loviisa NPP has decided to keep the number of assemblies, but to reduce the level of uranium enrichment. In both cases, the implementation of the project will make the operation of VVER-440 units in Hungary and Finland more efficient.”
Development of the fuel involved specialists from OKB Gidropress (part of Rosatom’s mechanical engineering division Atomenergomash), the AA Bochvar Research Institute of Inorganic Materials (VNIINM – part of TVEL) and Mashinostroitelny Zavod (MSZ) in Elektrostal. At the OKB Gidropress site, fuel assemblies and working cassettes of the new modification passed a complex of hydraulic, resource and vibration tests, and the fuel was manufactured by MSZ.
Loviisa 1&2 are VVER-440 pressurised water reactors. Loviisa 1 began commercial operation in 1977 and is currently licensed to operate until the end of 2027. Loviisa 2, which entered commercial operation in 1981, is licensed until the end of 2030.
