An increase in the operating temperature of photovoltaic (PV) panels caused by high levels of solar irradiation can affect the efficiency and lifespan of PV panels. This study uses numerical and experimental analyses to investigate the reduction in the operating temperature of PV panels with an air-cooled heat sink. The proposed heat sink was designed as an aluminum plate with perforated fins that is attached to the back of the PV panel. A comprehensive computational fluid dynamics (CFD) simulation was conducted using the software ANSYS Fluent to ensure that the heat sink model worked properly. The influence of heat sinks on the heat transfer between a PV panel and the circulating ambient air was investigated. The results showed a substantial decrease in the operating temperature of the PV panel and an increase in its electrical performance. The CFD analysis in the heat sink model with an air flow velocity of 1.5 m/s and temperature of 35°C under a heat flux of 1000 W/m2 showed a decrease in the PV panel’s average temperature from 85.3°C to 72.8°C. As a consequence of decreasing its temperature, the heat sink increased the open-circuit photovoltage (VOC) and maximum power point (PMPP) of the PV panel by 10% and 18.67%, respectively. Therefore, the use of aluminum heat sinks could provide a potential solution to prevent PV panels from overheating and may indirectly lead to a reduction in CO2 emissions due to the increased electricity production from the PV system.

In this study, dye-sensitized solar cells (DSSCs) were fabricated using double-layer photoanodes consisting of TiO2 nanoparticles (NPs) and Zn-doped TiO2 hollow fibers (HFs). The TiO2 HFs were prepared by co-axial electrospinning and used as the light-scattering layer in the DSSC. The thickness variations of the TiO2 NP and Zn-doped TiO2 HF photoanode layers affect the performance of the DSSC, especially the short-circuit photocurrent density. The thickness of the TiO2 NP layer significantly affected the absorbance of photons and N719 dye molecules in the double-layer photoanode, while that of the Zn-doped TiO2 HF layer affected the scattering of light, as indicated by the low light transmittance in the photoanode. Conventional DSSCs consist of single-layer photoanodes, and exhibit relatively low efficiency, i.e., 1.293% and 0.89% for TiO2 NP and Zn-doped TiO2 HF, respectively. However, herein, the highest efficiency of the DSSC (3.122%) was achieved with a 15 μm NP-5 μm HF photoanode, for which the short-circuit photocurrent density, open-circuit photovoltage, and fill factor were 15.81 mA/cm2, 0.566 V, and 34.91%, respectively.

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