A Scenario Study on Transition to the Closed Nuclear Fuel Cycle Using the Nuclear Energy System Modelling Application Package NESAPP

The paper presents the results of a case study on evaluating performance metrics for Russian nuclear energy deployment scenarios with thermal and sodium-cooled fast reactors in the closed nuclear fuel cycle. Ten possible scenarios are considered which differ in the shares of thermal and sodium-cooled fast reactors, including options involving the use of mixed uranium-plutonium oxide (MOX) fuel in thermal reactors. The evolution of the following performance metrics is estimated for the period from 2020 to 2100 based on the considered assumptions: annual and cumulative uranium consumption, needs for uranium enrichment capacities, fuel fabrication and reprocessing capacities, spent fuel stocks, radioactive wastes, amounts of plutonium in the nuclear fuel cycle, amounts of accumulated depleted uranium, and the levelized electricity generation cost. The models for assessing material flows, needs for nuclear fuel cycle services and economic performance metrics were elaborated using the nuclear energy system modelling application package NESAPP. NESAPP is a set of codes to support nuclear energy planning and nuclear fuel cycle transition scenario studies, including Nuclear Data Processing Spreadsheets (NUDAPS), Nuclide Evolution Exploring Tool (NUCLEX), Nuclide Composition Adjustment and Blending Tool (NUCAB), Material Flow Analysis Data Integration Tool (FANES), Economic Assessment Tool (ECNES) as well as a local reactor database including an atlas of one-group neutron cross-sections and neutron production/destruction rates. The elaborated nuclear energy system model considers the expected growth rates of electricity production and describes the main components of the industrial infrastructure, including nuclear reactors and fuel cycle facilities with specified technical and economic parameters. At various stages, the considered scenarios include thermal reactors with uranium oxide fuel, thermal reactors with partial loading of MOX fuel and sodium-cooled fast reactors with MOX fuel. The presented results show that the sustainability of the Russian nuclear energy system can be significantly enhanced through the intensive deployment of sodium-cooled fast reactors and the transition to the closed nuclear fuel cycle. It is highlighted some issues for further considerations, which will lead to more rigorous conclusions regarding the preferred options for the development of the national nuclear energy system. (authors)