Energy and exergy assessment of photovoltaic-thermal system using tungsten trioxide nanofluid: An experimental study

Abstract

• Serpentine pipes and WO3 nanofluids has proposed to improve PV module efficiency. • Reducing the PV module temperature by 21.4% has enhanced overall efficiency by 29.6%. • Heat transfer coefficient and Nusselt number have enhanced with low pressure drop. • Exergy losses and entropy generation were reduced by 10% and 34.8%, respectively. The temperature rising of the photovoltaic (PV) modules is a major issue leading to a reduction in their conversion efficiency and low output power. Therefore, removing heat from the PV module is necessary to permanently work and improve the electrical power output. Serpentine pipes and a thermal absorber plate has proposed with fluid circulation to reduce the PV cell temperature and improve their efficiency. The current work experimentally investigates the effect of using tungsten trioxide (WO 3 ) nanofluids on the PVT system's energy and exergy efficiency at different volume concentrations of 0. 5 vol%, 0. 75 vol%, and 1 vol%. The results indicated an increment in the electrical power output by 11.15 W due to reducing the PV temperature by 21.4% and enhancing the PVT overall efficiency by 29.6% compared with the cooling by Deionized (DI) water. Increasing the volume concentration of nanoparticles increased the Reynolds number, and the Nusselt number enhanced the heat transfer coefficient and increased the pressure drop. Improving the thermal properties of the nanofluid has increased the electrical exergy efficiency and lowered the thermal exergy efficiency due to the reduction in thermal exergy quality. Compared to DI water cooling, exergy losses and entropy generation were reduced by 10% and 34.8%, respectively.