Energetic and exergetic evaluation of a photovoltaic thermal module cooled by hybrid nanofluids in the microchannel

Abstract

Since reducing the local temperature of the solar cell boosts the performance of a concentrating photovoltaic–thermal, a microchannel heat sink technique is employed. Two hybrid nanofluids, Water-Aluminum oxide-Carbon Nanotube (water-Al2O3-CNT) and Water-Silver-Zinc Oxide (water-Ag-ZnO), are selected as the working fluids. The numerical model is designed in ANSYS CFX environment and the energetic and exergetic performance of the unit are taken into account. Reynolds number and nanoparticles volume fractions are the main variables for this simulation. The outcome of this study shows that more effective reduction in the cell temperature is achieved by using hybrid nanofluids compared to the pure water, in particular at lower Reynolds numbers. In detail, at Reynolds number equal to 10, it is observed that the electrical efficiency for water-Al2O3-CNT and water-Ag-ZnO nanofluids grow by 3% and 2%, respectively. Likewise, the exergy efficiency of the Concentrating Photovoltaic–Thermal panel is remarkably enhanced by taking advantage of the hybrid nanofluids. Finally, it can be concluded that employing hybrid nanofluids in solar systems could technically yield a desirable performance.

Keywords

• Solar energy
• Photovoltaic thermal
• Hybrid nanofluid
• Microchannel
• Exergy