一种具有直接水-电池接触的创新光伏光热系统：能量、㶲与可持续性分析

Abstract Current photovoltaic thermal systems (PVT-Ss) have numerous limits that hinder their efficiency and widespread adoption. Among the main gaps identified in the literature are: (a) using weighty and costly heat exchangers (HE), (b) absence of straight connection among fluid and Photovoltaic (PV), which limits cooling efficiency, and (c) the use of absorber plates, which cause mechanical stresses due to thermal expansion, while also increasing the system’s weight and cost. This study proposes a new PVT-S configuration featuring a simplified and lighter design to overcome these limitations. The analysis focuses on the impact of varying the number of holes and the thickness of the fluid slick on energy and exergy performance, as well as on pressure drop. The effects of solar irradiation and fluid mass flow rate are also examined. Additionally, an assessment of the system’s durability has been conducted. The results of three-dimensional numerical simulations, carried out using COMSOL Multiphysics software, have been validated against experimental and numerical data from the literature. These results show that increasing the number of holes from 10 to 60 has a negligible impact on cell temperature (0.3 °C), but reduces the pressure drop by 109 Pa. Among the different configurations studied, the one incorporating a 1 mm fluid slick proved to be the most efficient, with an electrical efficiency of 13.76 %, a thermal efficiency of 79.80 %, and an overall exergy efficiency of 15.96 %. However, this configuration generates higher pressure drops, reaching 848 Pa and 874.64 Pa compared to the 3 mm and 5 mm systems, respectively. Lastly, growing irradiance and decreasing mass flow rate (FRT) enhance the durability factor.