Three-dimensional heat transfer studies of glazed and unglazed Photovoltaic/Thermal systems embedded with phase change materials

Abstract

• The photovoltaic/thermal modules assembled with PCMs were numerically analyzed. • The assembled photovoltaic/thermal structures were evaluated from the energetic and exergetic views. • Embedding PCMs in photovoltaic/thermal modules are benefit for the CO 2 mitigation. In this study, a three-dimensional numerical simulation is carried out to implement a comparative analysis between the glazed and unglazed photovoltaic/thermal (PV/T) integrated structures incorporated without or with phase change materials (PCMs) at distinct locations using water as a coolant. Accordingly, six glazed and unglazed PV/T or PV/T-PCM configurations are designed through burying the water pipes within the PCM and positioning an additional PCM layer with different melting temperature from the upper one. The performance of the proposed layouts is evaluated and compared from the energy and exergy points of view. The effect of coolant flow rate is also evaluated in both the laminar and turbulent regions along with assessing the environmental impact of the proposed modules to analyze the daily CO 2 reduction. The results show that burying the water pipes inside the PCM beneath the PV/T module yields a significant improvement of the overall performance. Also, the electrical energy generated from unglazed modules is somewhat higher than that generated from the glazed modules, however the daily thermal energy output for the glazed modules is marginally higher than that generated from unglazed layouts having the same layer arrangement. Among the proposed structures, the glazed and unglazed PV/T modules integrated with dual PCMs achieve the highest daily average energetic and exergetic efficiencies, respectively.