ABSTRACT
The operation and effectiveness of a solar-powered underground water pumping system are affected by many environmental and technical factors. The impact of these factors must be investigated to be considered when developing these systems and to ensure their dependability. This study evaluated the dependability and performance of photovoltaic water pumping system (PVWPS) under real operating conditions by examining the effects of solar irradiance, panels' temperature, and components' efficiency. From December 2020 to June 2021, experiments were conducted on a 10 hp PVWPS located in Bani Salamah, Al-Qanater-Giza Governorate, Egypt, at latitude 30.3° N, longitude 30.8° E, and 19 m above sea level. The irradiance values reached 755.7, 792.7, and 805.7 W/m2 at 12:00 p.m. in December, March, and June, respectively. Furthermore, the irradiance has a significant impact on the pump flow rate, as the amount of pumped water during the day reached 129, 164.1, and 181.8 m3/day, respectively. The panels' temperatures rose to 35.7 °C, 39.9 °C, and 44 °C, respectively. It was observed that when the temperature rises by 1 degree Celsius, efficiency falls by 0.48%. The average efficiency of photovoltaic solar panels reached its highest value in March (13.8%) and its lowest value in December (13%).
ABSTRACT
The photovoltaic (PV) solar panels are negatively impacted by dust accumulation. The variance in dust density from point to point raises the risk of forming hot spots. Therefore, a prepared PDMS/SiO2 nanocoating was used to reduce the accumulated dust on the PV panels' surface. However, the effectiveness of these coatings is greatly influenced by geographical and climatic factors. Three identical PV modules were installed to run comparable experimental tests simultaneously. The first module is coated with the prepared PDMS/SiO2 nanocoating, the second is coated with commercial nanocoating, and the third module is uncoated and serves as a reference. The prepared nanocoating was hydrophobic and had a self-cleaning effect. The fill factors for the reference panel (RP), commercial-nanocoated panel (CNP), and prepared-nanocoated panel (PNP), were 0.68, 0.69, and 0.7, respectively. After 40 days of exposure to outdoor conditions, the dust densities on the RP and PNP panels' surfaces were 10 and 4.39 g/m2, respectively. Thus, the nanocoated panel's efficiency was found to be higher than that of the reference panel by 30.7%.
