The first batch of an improved type of nuclear fuel assemblies with a reduced content of erbium oxide (PSOE – Ponizhennim Soderzhaniem Oksila Erbiya) has been loaded into the RBMK reactors at units 3&4 of Russia’s Kursk NPP. The fuel was manufactured at the machine-building plant (MSZ – MashinoStroitelnom Zavode) in Elektrostal, Moscow region.
“Loading fuel assemblies with a reduced content of erbium oxide is an important stage in the modernisation programme aimed at improving the safety and efficiency of RBMK-1000 reactors,” said Denis Pereguda, Deputy Chief Engineer for Safety & Reliability. At Kursk NPP. “It was carried out with the permission of [regulator] Rostechnadzor and is no different from loading other types of fuel.”
He added: “The decision to optimise the fuel composition was based on independent computational studies by specialised institutes such as the National Research Center Kurchatov Institute, the All-Russian Research Institute for the Operation of Nuclear Power Plants (VNIIAES – Vserossiiskii Nauchno Issledovatelskii Institut po Expluatatsii Atomnikh Elektrostantsii) and others, and will increase fuel efficiency by about 5%.”
Pereguda explained that the need to change the fuel composition arose due to the performance of work on the resource characteristics of graphite masonry at RBMK-1000 power units to improve safety and extend the life of RBMK reactors. Calculations have shown that the new type of fuel will ensure optimal conditions for further operation of the reactor plant, as well as maintain the parameters of its controllability and protection.
The PSE fuel assemblies were loaded together with the placement of reusable fuel assemblies in the reactor. This will make it possible to make the most efficient use of the fuel resource unloaded from Kursk 1&2 that have been shut down for decommissioning. The use of TSE fuel assemblies also supports continued production of the cobalt-60 isotope used in healthcare, industry and agriculture.
“The modernisation of existing power units, including the transition to a new type of fuel, and the extension of service life are our contribution to the fulfilment of the strategic task set for Rosatom by the President of the country: to increase the share of nuclear generation in the total energy balance of Russia to 25% by 2045,” said Andrey Osharin, Acting Director of Kursk NPP.
Loading fuel with optimised erbium content has also begun at the Kursk-II NPP. Kursk-II will replace the currently operating Kursk NPP, which comprises four ageing RBMK reactors (two of which are now closed) with four new units comprising Generation 3+ VVER-TOI reactors. Unit 1 began commercial operation at the end of April. unit 2 is expected to begin operation in 2027, and the construction and commissioning of units 3&4 are planned for 2042.
