Influence of single and hybrid water-based nanofluids on performance of microgrid photovoltaic/thermal system

Abstract

Invoked by a rising demand for energy in greenhouse production, the industry has adopted a new approach by incorporating photovoltaic panels. A photovoltaic/thermal (PVT) system was used both inside and outside of a greenhouse to simultaneously supply electricity and heating. The experiments were carried out in both indoor and outdoor conditions using pure water cooling, single nanofluids (0.1, 0.3, and 0.5 wt%), and hybrid nanofluids (SiO2-Al2O3; 0.1–0.1, 0.3–0.3 and 0.5–0.5 %wt). The highest electrical and thermal efficiency values were 13.17% and 65.05% for the outdoor PV panel , and 11.47% and 56.08% for the indoor panel using hybrid nanofluid with the 0.5–0.5 concentration of (wt%). The results also indicated that the overall efficiency of the indoor and outdoor systems were 48.54% and 63.26%, respectively, when using pure water. Hybrid nanofluid, however, increased the overall efficiency of both indoor and outdoor systems by 68.09% and 75.26%. This finding revealed the larger effect of the nanofluid on the indoor system than on the outdoor greenhouse. Accordingly, the efficiency gap of the two systems was dropped from 14.72% to 7.17% when working with nanofluid, instead of pure water. Additionally, the results showed that the overall efficiency of the indoor system had the closest efficiency to that of the outdoor system when using the single and hybrid (Al2O3-SiO2) water-based nanofluids.