The concept of creating a maneuverable power plant based on a small modular reactor

Abstract

Purpose. To develop a maneuverable power plant (MPP) based on the NuScale small modular reactor (SMR) by selecting a thermal scheme structure for a steam turbine installation using minimal additional equipment and ensuring its operation in both nominal and peak modes with maximum efficiency. This also includes ensuring its maneuverability through the use of hydrogen technologies for generating, storing, and returning energy to the steam turbine cycle. Methodology. The study employed the method of mathematical modeling of thermodynamic cycles of thermal schemes of steam turbine installations (STI) with concentrated parameters, which makes it possible to describe the dynamics of systems consisting of discrete elements that are thermodynamic systems. Findings. Various structural options for the thermal scheme of the MPP based on the NuScale SMR for nominal operation were developed and mathematically modeled, followed by a comparative analysis of their energy efficiency. As a result, a scheme and operational parameters were selected with the highest electrical efficiency (net), which allows increasing the net efficiency of the NuScale SMR-based power plant from the developers’ announced 28 to 32.8 %. A thermal scheme for the MPP based on the SMR with an energy storage system was proposed. Applying this scheme allows increasing the net efficiency of a power plant based on NuScale SMR in peak mode to 34.8 %. Originality. A concept for creation and schematic solution for a prospective MPP based on an SMR capable of accumulating electrical energy was proposed. The main innovative solution regarding the structure of the technological scheme of the MPP based on the SMR is the organization of its operation in nominal and peak modes, which fundamentally differ in the thermodynamic cycle. In the nominal mode, the steam turbine installation operates on a thermodynamic cycle with steam separation, and in the peak mode without it, by increasing the temperature of fresh steam as a result of burning hydrogen and oxygen. Hydrogen and oxygen are produced in an electrolyzer during the power plant’s operation in the nominal mode by using the generated electricity “excess”. Practical value. Small modular reactors are currently mainly in the development stage. Additionally, the non-nuclear part of the SMR-based power plant, namely the STI, has not received sufficient attention, as evidenced by the literature. However, it plays a crucial role in the overall efficiency of the installation. The study focuses on the highly relevant issue of improving the efficiency of an SMR-based power plant by developing the structure of the STI thermal scheme involving hydrogen technologies. This will help reduce dependence on fossil hydrocarbons in the total volume of primary fuel and enable sustainable functioning of the Ukrainian energy system, as well as contribute to the preservation and improvement of the environmental state.