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Mechanical integrity of a Photovoltaic (PV) module plays a major role in its performance and electrical output. Mechanical loads which include loads produced by wind, snow, rain, and hail tend to degrade the performance of PV module by generating stresses and enhancing micro-cracks and defects. This research aims to investigate the impact of wind loads on the performance of PV modules, particularly the degradation in its power output. A load of 2400 Pa was applied as per international standards (ASTM E1830-15 and IEC-61215). A total of four PV module samples, of the same specifications with 60 W rated power, were initially subjected to solar flash testing and Electroluminescence (EL) imaging. This was followed by three cycles of mechanical load test. After the mechanical load tests, the modules were again subjected to solar flash testing and EL imaging and the results were compared. It was noted that static wind load degrades the mechanical integrity of photovoltaic modules in two ways; by aiding the propagation of existing cracks and initiating new cracks. This loss of mechanical integrity degraded the power output of PV module. Maximum drop of 2% in the power output and 0.27% in the efficiency was observed. In addition, the average increase of 3.37% in the series resistance was observed indicating decrease in performance. [ABSTRACT FROM AUTHOR]

Continuous elevation in temperature of photovoltaic (PV) panels results in the decline of PV electric power production. This paper presents the experimental methodology tested outdoors in Taxila, Pakistan to lower PV temperature with the simultaneous use of nanofluid (graphene/water) and phase change material (RT-35HC). Performance of this hybrid PVT system in terms of PV temperature, electrical efficiency, thermal efficiency and overall efficiency, is compared with PVT/PCM system integrated with water flowing through tubes inside PCM, PV/PCM system and conventional PV. Effects of varying volume concentrations (0.05%, 0.1%, 0.15%) of graphene nanoparticles as well as flowrates (20, 30, 40 LPM) are also examined and it is found that the best performance is achieved with 0.1 vol% nanoparticle concentration and 40LPM flowrate. From the experimentation results, maximum reduction in PV temperature is observed to be 23.9 °C, 16.1 °C and 11.9 °C with nanofluid-based PVT/PCM system, water-based PVT/PCM system and PV/PCM system respectively, with maximum enhancement in electrical efficiency of 23.9%, 22.7% and 9.1% respectively as compared to conventional PV. It is also found that nanofluid-based hybrid PVT/PCM system shows 17.5% higher thermal efficiency as compared to water-based hybrid PVT/PCM system, and overall efficiency enhanced by 12%. Thus, results ensure the best performance with hybrid PVT system integrated with nanofluid and PCM simultaneously. • Novel solution for thermal management of PV using nanofluid and PCM simultaneously. • Nanofluid-PCM system was most effective followed by water-PCM and PCM alone systems. • At 0.1 vol% conc. and 40LPM flowrate, nanofluid-PCM system showed best performance. • PV electrical efficiency enhanced by 23.9% as compared to conventional PV. • Nanofluid-PCM PVT system showed 12% higher overall efficiency than water-PCM PVT system. [ABSTRACT FROM AUTHOR]

Photovoltaics thermal (PV/T) management has attracted much attention in research, with a particular focus on improving its performance in the current globalized market. As the continuous elevation of PV surface temperature due to direct sun rays degrades PV/T performance, effective cooling of PV panels has been identified as a way of improving efficiency. Thermal regulation strategies have suggested that water, nanofluids, air, phase change materials (PCM), and nano-enhanced PCMs can be varied for cooling purposes. The current study considers silica and carbon black nanoparticles dispersed in phase change materials for two purposes: firstly, to increase the speed of storing and releasing thermal energy of nano-enhanced PCM; and secondly, for improving the thermal conductivity of PCM. The experimentation of this study was conducted in outdoor conditions of Taxila, Pakistan during the month of March 2020. To construct the nano-enhanced PCM, Silica (SiO 2) and Carbon Black (CB) NPs were added to PT-58 at concentrations of 0.25 wt % and 0.5 wt %. NPs at 0.5 wt % concentration in CB/PT-58 as a nano-enhanced PCM showed the topmost performance in cooling of a PV panel. The experimentation depicted a maximum decrease in temperature of the system using CB/PT-58 and SiO 2 /PT-58, at approximately 9.74 °C and 8.92 °C respectively, where the electrical efficiency of the systems improved to 12.07% and 12.00% respectively, at a concentration of 0.5 wt %. The maximum percentage increment in electrical power was 30.45 % and 30.23 % respectively, in the case of CB/PT-58 and silica/PT-58 nano-PCM at 0.5 wt % of NPs in base PCM. The results elucidate that the performance of the system using the CB/PT-58 nano-PCM as a cooling method was higher than the silica/PT-58 nano-PCM. [Display omitted] [ABSTRACT FROM AUTHOR]