Design optimisation and performance appraisal of a combined cooling, heating and power system primed with Maisotsenko combustion turbine cycle

Abstract

Buildings are the significant primary energy consumption and pollutant emission contributors in a modern city. Distributed multi-generation systems such as combined cooling, heating and power (CCHP) systems are considered an alternative to fulfil the energy saving requirements in the building sectors. In this study, a CCHP system primed with Maisotsenko combustion turbine cycle (MCTC) was considered with its performance compared with that primed with a simple gas turbine with recuperator (SGTR). With dynamic models of the CCHP systems constructed using TRNSYS, a design optimisation was conducted using genetic algorithm to determine the system component size and number based on the best year-round cost saving. A study case which consisted of building complexes in a district scale was used for investigation under two climatic conditions. The simulation results showed that the relative performances of both CCHP systems depended on the load profiles which differed from the situations when both prime movers were used solely for power generation. In a heating-dominated application, the performance of the MCTC-primed CCHP system was better than the SGTR-primed one only during the summer period and that the year-round performance was inferior to the latter one. Last but not the least, a parameter study was conducted which showed the benefit reduction of CCHP system with the decreasing of public grid price and increasing fuel gas price.