Simulation of air-cooled PV/T air conditioning system for cooling and power cogeneration

Abstract

The traditional photovoltaic/thermal (PV/T) air conditioning system usually uses a PV/T heat exchanger as the condenser, of which poor heat dissipation performance leads to an undesirable system cooling capacity. This study proposes an air-cooled PV/T air conditioning system, comprising an air-cooled condenser and a PV/T condenser combined in series. Experiments are carried out under daytime and nighttime conditions in summer, and numerical simulations are conducted to analyze the influence of different factors on the system performance. EVAP-COND, FLUENT and EES software are adopted to calculate the air-cooled condenser model, PV/T condenser model and system performance under different weather conditions, respectively. Results show that the heat dissipation rate of system condenser increases with the outdoor wind speed, refrigerant mass flow rate and inlet temperature, while decreases with the solar irradiance and outdoor temperature. Remarkably, the refrigerant mass flow rate has the most significant impact on the heat dissipation performance of system condenser. When the refrigerant mass flow rate increases from 10 kg/h to 50 kg/h, the heat dissipation rate of system condenser increases from 639 W to 3116 W. Moreover, the system cooling performance is better under nighttime conditions, as its COP is 20.0 % and 123.7 % higher than that under cloudy and sunny daytime conditions, respectively.