Numerical study of a water-based photovoltaic-thermal (PVT) hybrid solar collector with a new heat exchanger

Abstract

Based on the latest information provided by researchers, previous studies have identified two major gaps in the literature: the lack of research on channel-box PVT collectors (PVT-Cs) and the absence of studies on the surface temperature distribution for these systems. To fill these gaps, we proposed a new channel-box PVT-C. We then numerically evaluated its performance, examining its energy aspects under various operating conditions. This evaluation was carried out using COMSOL Multiphysics® software, based on the finite element method (FEM). In addition, we validated our 3D numerical model by comparing it with numerical and experimental data in the literature. The results of this study show that increasing the fluid flow rate increases power and electrical efficiency (EE), and that the optimum cooling water flow rate is around 180 L/h. In addition, the overall efficiency (OE) increases with solar irradiation. Furthermore, the electrical power (EP) increases from 37.06 W to 140.48 W for the PV system, and from 38.45 W to 187.02 W for the PVT-C, when the irradiation increases from 2 × 102 to 103 W/m², while maintaining an optimum flow rate of 180 L/h. In terms of efficiency, the PVT-C has an electrical, thermal and overall efficiency of approximately 12.11 %, 78.59 % and 90.7 % respectively for an irradiation of 103 W/m². However, the EE of the PV panel is only 9.09 %, or 3 % less than the PVT-C.

Keywords

• PVT collector
• Conjugate heat transfer
• Performance
• Finite element method
• COMSOL multiphysics®