Energy and environmental performance of a grid-connected concentrating photovoltaic thermal system for residential buildings in Iran

This paper evaluates the performance of a concentrating photo-voltaic thermal (CPVT) hybrid system for space heating, providing hot water, and grid-connected (GC) electricity generation in the city of Isfahan, Iran. The GC-CPVT system is a ground-mounted 5.63 kWp rated power system oriented in a north-south direction to achieve the maximum power output. The annual and monthly modeling of the system is performed by Polysun® simulation software. The system specifications are described and the heating and electrical energy demand of the building are determined. The GC-CPVT performance simulation is then conducted based on the meteorological data of the location. The monthly simulation results of the GC-CPVT system in the studied location show that the yield factor varies from 138.8 to 183 kWh/kWp, the reference yield from 170.3 to 253.5 kWh/kWp, and the performance ratio from 70.3 to 82.2%. The maximum annual AC electricity generated is 10752 kWh. Furthermore, the CPVT system generates a considerable amount of heat. The annual solar fraction values for covering domestic hot water and space heating are achieved 78.3% and 35.3%, respectively. The monthly solar fraction covered by the CPVT system also varies from 32 to 100%. The environmental performance of the GC-CPVT system indicates that the contribution of such a system to CO2 emission reductions exceeds 8 tons of CO2 per year.