Exergy analysis for small modular reactor hybrid energy system

Nuclear hybrid energy systems (NHES) with the capability to store energy will advance the development of renewable energy technologies by providing reliable, non-carbon emitting, and integrated base-load nuclear energy. Small modular reactors (SMRs) will be significant in establishing hybrid energy systems because of their inherent financial advantages over larger commercial reactors; flexible deployment and faster onsite assembly; and ability to closely match required energy needs for industrial process heat applications. An SMR is a thermal energy plant comprised of many complex systems that interact with each other and their surroundings. To study such a system and set appropriate prices for outputs, it is important to assess thermoeconomics or the effective utility and costs of all resources. At its core, thermoeconomics is based upon the quality of energy, or exergy, flowing into and out of each component within a system. Limited research into the thermoeconomics behind SMRs has been performed, leaving an important gap in understanding. This article presents relevant exergetic cost theory and details methods behind an exergy analysis for an SMR-wind-storage system. To perform this analysis, both the physical and economic environments are identified to provide information on how overall system efficiencies and costs may be analyzed. The physical environment incorporates the actual system components, necessary raw materials, and the surroundings or reference environment. The economic environment refers to the upfront installation and operational costs in addition to market prices. In a purely thermodynamic exergy analysis, the exergetic cost may be determined from the physical environment alone and describes the necessary exergy for production to occur. To improve or optimize a system, system efficiency must be balanced with economics to make NHES more competitive and further their development.