Part-Load Strategy Definition and Preliminary Annual Simulation for Small Size sCO2-Based Pulverized Coal Power Plant

Abstract In the near future, due to growing share of variable renewable energy in electricity mix and lack large-scale storage, coal plants will have shift their role from base-load operation providing fluctuating back-up power. However, current power plants, based on steam Rankine cycle, are not optimized for flexible part-load operation, resulting an intrinsic inadequacy fast load variations. The founding idea H2020 sCO2-Flex project is improve flexibility pulverized by adopting supercritical CO2 Brayton cycles. Despite extensive literature about design sCO2 there still limited discussion strategies be implemented maximize system efficiency during operation. This paper aims provide deeper insight potential recompressed cycle with high-temperature recuperator (HTR) bypass configuration small modular (25 MWel). Analysis focuses both a preliminary sizing each component comparing different operating strategies. Results demonstrate that can achieve competitive nominal thanks progressive increase heat exchangers effectiveness. Moreover, they operated down 20% electric increasing range plants. Finally, possibility optimize minimum pressure ensures safe compressor far surge line performance at low load.