A comparative experimental investigation of energetic and exergetic performances of water/magnetite nanofluid-based photovoltaic/thermal system equipped with finned and unfinned collectors.

The intent of the present investigation is to conduct; experimentally, the effects of nanofluid of water/magnetite and flow channel arrangement on photovoltaic thermal (PVT) systems. Three different configurations of the collector in PVT were researched in various nanofluid's flow rate of M ˙ = 20.0 − 80.0 (k g / h r) , and nano concentration of φ = 0.0 − 2.0 %. The studied arrangements of flow channels in the collector are a sheet-and-plain serpentine tube (PVT-0S), a sheet-and-finned serpentine tube with four fins (PVT-4S) and a sheet-and-finned serpentine tube with eight fins (PVT-8S). The electrical efficiency is compared between the cited three cases and the PV panel without cooling system. The maximum energetic, exergetic and electrical performances were found at the flow rate of M ˙ = 80 (k g / h r) and nano concentration of φ = 2.0 %. It was observed that the PVT-8S system provides the most efficient configuration since the overall energy efficiency (η) in the PVT-8S system are 5.87 % , and 15.59 % higher than the PVT-4S, and PVT-0S systems. Further, the PVT-8S system demonstrated the maximum value of exergy efficiency (Γ = 14.51 %) compared to other studied systems. It was also shown that the electrical efficiency (Λ) augments significantly with the adding the cooling systems to the PV panel. The increase in the electrical efficiency was 12.06 % , 10.87 % , and 8.40 % for the PVT-8S, PVT-4S, and PVT-0S systems; respectively. • The maximum energetic performance is obtained at the flow rate, and volume fraction of 80 (kg/hr) and 2.0%. • The highest overall energy and exergy efficiencies were achieved for the PVT-8S system. • PVT-8S, PVT-4S, and PVT-0S have 12.06%, 10.87%, and 8.40% higher electrical efficiency than PV panel. [ABSTRACT FROM AUTHOR]