Steady-State Thermal-Flow Analysis of a NuScale SMR Cogeneration System for District Heating

Abstract

Small modular reactors (SMRs), including the NuScale design, are primarily intended for electricity production. In the context of the ongoing energy transition in Poland, aimed at reducing the use of fossil fuels, SMRs may serve as a low-emission alternative to conventional power generation sources. In order to make better use of them, SMR reactors can operate in a cogeneration system, producing both electricity and district heating. The article presents the concept of using the NuScale SMR nuclear reactor in a cogeneration system. A model of the SMR system with a heating component was created in the Ebsilon program. A heating component consisting of two heat exchangers was proposed. In order to minimize interference with the original cycle configuration, one of the heat exchangers was assumed to be supplied with steam from the same turbine extraction point as the low-pressure regenerative heat exchanger. The second heat exchanger would be supplied from the same steam extraction point as the first high-pressure regenerative exchanger. The performed analysis indicates that a cogeneration configuration based on a single NuScale module can deliver approximately 100 MWth of thermal power, which is sufficient to supply a district heating network of small or medium size.