Thermoeconomic assessment and multi objective optimization of a solar micro CCHP based on Organic Rankine Cycle for domestic application

This paper proposes a novel micro solar Combined Cooling, Heating and Power (CCHP) cycle integrated with Organic Rankine Cycle (ORC) for summer and winter seasons. The thermal storage tank is installed to correct the mismatch between the supply of the solar energy and the demand of thermal source consumed by the CCHP subsystem, thus the desired system could continuously and stably operate. The cycle is analyzed and optimized from the viewpoint of thermodynamics and thermoeconomics. For summer mode, the thermal efficiency, exergy efficiency and product cost rate are found to be 23.66%, 9.51% and 5114.5 $/year, while for winter mode, these values are 48.45%, 13.76% and 5688.1 $/year, respectively. Five key parameters, namely turbine inlet temperature, turbine inlet pressure, turbine back pressure, evaporator temperature and heater outlet temperature are selected as the decision variables to examine the performance of the overall system. The thermal efficiency, exergy efficiency and total product cost rate are selected as three objective functions and Genetic Algorithm (GA) is employed to find the final solutions to both single and multi-objective optimizations of the system. The results indicate that in summer, thermal efficiency, exergy efficiency and total product cost rate in optimum case are improved to 28%, 27% and 17%, respectively, while in winter, these values are 4%, 13% and 4%. (C) 2015 Elsevier Ltd. All rights reserved.