Numerical investigation on the optimum performance output of photovoltaic thermal (PVT) systems using nano-copper oxide (CuO) coolant

Abstract

Nanofluids application has now become a conventional cooling medium in PVT technology. However, there is little knowledge in the current literature about the PVT operational conditions for optimum performance. This paper aims to investigate the PVT optimum operating conditions with CuO nanofluid application. TRNSYS simulation platform is used in this investigation by developing a numerical equation-based model. The input parameters investigated are nanofluid volume concentration from 0.10 % to 0.50 % and fluid flow at 60 kg/h, 80 kg/h and 120 kg/h. The influence of these inputs was observed on the system’s PV cell temperature, electrical efficiency, thermal efficiency, net electrical output and pump power consumption. The results showed that at 60 kg/h flow, the increment in nanofluid concentration from 0.10 % to 0.50 % caused an increase in electrical efficiency by 1.11 % with a 3.30 % increase in thermal efficiency. Similarly, at 0.10 % volume concentration, when mass flow was raised from 60 to 80 kg/h, the improvements in electrical efficiency were 1.46 % and for 80–120 kg/h the electrical efficiency of the system dropped by 0.08 % due to higher pump power consumption. Overall, the electrical efficiency improved by 1.36 % for 60–120 kg/h mass flow. The thermal efficiency improvements were 4.15 %, 1.07 % and 5.27 %, at the same corresponding flow rates. Net electrical output analysis of the system showed that an increase in volume concentration and fluid flow rate changes the density of nanofluid which in turn increases the pump power consumption. The analysis also identified that the optimal operating conditions for the system are 0.10 % CuO concentration and 80 kg/h mass flow.