Modeling and assessment of long-term development scenarios of Ukraine's nuclear energy

The paper presents the results of modeling and comparative analysis of long-term scenarios of the expansion of the generating capacities of Ukraine's Power System assuming decommissioning or extension of nuclear power plants' (NPPs) life. Development of scenarios and model calculations was carried out using the optimization modeling tool "WASP-Ukraine", developed on the basis of IAEA software WASP-IV designed to find the economically optimal generation expansion policy within user-specified constraints. The model "WASP-Ukraine" is based on linear programming technique. Modeling baseline and alternative scenarios made for the period up to 2030 and the base year is 2014. The study examined six scenarios assuming decommissioning and extension of NPP life in accordance with international practice. The share of nuclear power in electricity production in Ukraine in 2030 under different scenarios varies from 11% to 48%. In the scenarios, which minimize the role of nuclear power, compensation of decommissioned NPP is provided by renewables or by conventional thermal power plants. Comparative analysis of the scenarios is conducted by four criteria: cost efficiency (average production cost of electricity generated in a power system); environmental sustainability (total emissions of sulfur oxides (SO2) and nitrogen oxides (NOx)); reliability of the power system and electricity supply (aggregated loss of load probability (LOLP) and the energy not served (ENS) indicators); provision of power plants with primary energy resources (steam coal). The comparative analysis proved that scenarios assuming extension of NPP life are more acceptable and efficient by all selected criteria comparing to those assuming decommissioning of NPP after their life period. Thus, maintaining the dominant role of nuclear energy in Ukraine's power balance at least until 2030 is justified.