Economic analysis for solar photovoltaic/thermal hybrid domestic hot water system

Solar Photovoltaic/Thermal hybrid system (PV/T) produces hot water and electricity simultaneously supplied for household appliances. Dynamic system simulation software TRNSYS was adopted to establish the typical family water scale photovoltaic/thermal hybrid hot water system, for which the meteorological data in Changsha area, Hunan province were used. Based on the TRNSYS results and the local prices data, the system economic analysis and sensitivity analysis were performed. The results showed that the dynamic payback period of the investment ranged from 7.6 to 16 years, the present value of the comprehensive energy price remained less than 0.3 CNY/KWh, and the internal rate of return ranged from 11% to 24%. The results of the economic analysis verified the economic feasibility of the PV/T domestic hot water system. Sensitivity analysis indicated that the annual growth rate of electricity and base discount rate were important factors and the increase of annual growth rate of electricity improved the economic property of the system obviously.