Experimental evaluation of energy and exergy performance of a nanofluid-based photovoltaic/thermal system equipped with a sheet-and-sinusoidal serpentine tube collector

Abstract

The chief goal of this survey is about comprehensively examine a photovoltaic-thermal (PVT) system with a sheet-and-sinusoidal serpentine tube collector (PVT-S) experimentally from the perspective of energy, exergy and entropy generation. The results are compared with those of the PV module deprived of cooling and the PVT unit accompanied by a sheet-and-plain serpentine pipe collector (PVT-P). A water based nanofluid (NF) containing magnetite nanoadditives is considered as a coolant. The effects of volume concentration of nanoadditives (ϕ), NF mass flow rate (m˙nf), amplitude of the sinusoidal serpentine tube (a), and wavelength of the sinusoidal serpentine tube (w) on the performance metrics of the PVT unit are considered. The outcomes declared that the combined use of sinusoidal serpentine tube and NF leads to augmentation of energetic and exergetic performances of the PVT unit. According to the results, the first-law thermal, electrical and overall efficiencies of the PVT-S unit are 20.67–30.63%, 1.94–2.32% and 8.83–18.28% bigger than those of the PVT-P unit, respectively. In addition, the second-law thermal, electrical and overall efficiencies of the PVT-S unit are 10.56–26.68%, 1.94–2.32% and 2.44–4.57% greater than those of the PVT-P unit, respectively. Moreover, it was demonstrated that the increase of ϕ and m˙nf and the decrease of w result in an increment of performance features of the studied PVT units. Furthermore, it was found that among the entire the items considered in the survey, the best energetic and exergetic performances and the lowest entropy generation rate belongs to the NF-based PVT-S unit at ϕ=2%, m˙nf=80 kg/h, a=5 mm and w=60 mm.