Energy and exergy evaluation of a baffled-nanofluid-based photovoltaic thermal system (PVT)

Abstract

In this paper, a differently baffled-nanofluid-based photovoltaic thermal module is proposed and numerically evaluated from both an energy and an exergy perspective. To obtain the optimum module, several systems including; the PV module (PVM), the simple channel collector PVT module (SPVTM), and the baffled channel collector PVT module (BPVTM), were investigated using three working fluids, including pure water, CuO/water nanofluid, and CNT/water nanofluid. Following a comparison of these seven various case studies, the overall performance of the suggested system from both energy and exergy in order to choose the ideal system was assessed about several variables, such as flow rate, radiation intensity, volume fraction, and wind speed. The results show that baffle-based PVT systems outperform simple-based modules in terms of efficiency. Also, the performance of the baffled model is well amplified by using nanofluids. When compared to the SPVTM/water, the BPVTM/CuO and BPVTM/CNT increase thermal power by 9.46 and 14.0%, respectively, increase electrical power by 1.41 and 2.12% and also reduce solar cell temperature by 9.22 and 13.82%. Power generation from the BPVTM/CNT is the highest among the other cases investigated. The overall exergy efficiency of the baffled PVT module with CuO/water and CNT/water increases by 0.44% and 2.38%, respectively, in comparison to that with water. The findings suggest that while low flow rates are generally better for the system's exergy performance, high flow rates are more advantageous from an energy perspective. The performance of the PVTM with CuO/water nanofluid is marginally better than the unit with water. However, the CNT/water nanofluid systems significantly outperform the water and CuO/water systems.