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Photovoltaic power generation can directly convert solar energy into electricity, but most of the solar energy absorbed by the photovoltaic panel is converted into heat, which significantly increases the operating temperature leading to a reduction in the power generation efficiency of the panels. To reduce the working temperature of photovoltaic panels and improve the photoelectric conversion efficiency, this paper installs aluminum fins and air channels at the traditional photovoltaic cell back sheets and cools them with forced-circulation cooling through fans. The relationships between fin spacing, fin height, air channel inlet wind speed and panel temperature, power generation, and electrical efficiency were investigated. The results show that the temperature of the photovoltaic panel decreases and then increases with the decrease of the fin spacing during natural convection and gradually decreases with the increase of the fin height. The use of forced-circulation cooling technology can effectively reduce the PV panel temperature and increase the net power generation. When the solar radiation intensity is 1000 W/m2, the ambient temperature is 35°C, the fin spacing is 6 mm, the height is 80 mm, the inlet wind speed is 1 m/s, the net generating power reaches the maximum value, and the net generating power and the electrical efficiency are increased by 14.6% and 2.25%, respectively. [ABSTRACT FROM AUTHOR]

As energy yields of photovoltaic modules are highly related to local climate and ambient conditions, it is necessary to assess the energy-yield performance of PV modules under various operating conditions. This work compares commercial crystalline silicon (c-Si) based PV modules (including mono c-Si Al BSF, mono c-Si PERC, multi-crystalline (mc-Si) Al BSF, and n-type c-Si solar cells) sampled from 27 PV module manufacturers located in the Asia-Pacific region between 2016 and 2022. Several test items were compared including: (i) light-induced degradation (LID), (ii) irradiance-temperature-efficiency (GTE) matrix, (iii) angular response and (iv) temperature coefficients, which are correspondingly performed according to IEC 61215-1, -1-1, -2 and IEC 61853-1, -2. The coefficient of variation (CoV) was calculated to express the module-to-module differences within similar technology types. Benefiting from the technological innovation of c-Si based PV modules, emerging PV modules feature better performance in some extreme ambient conditions, such as low irradiance, high ambient temperature, and high ratio of diffuse irradiance. The analysis of CoV indicates that the difference of irradiance-dependent and thermal behavior between modules within the same technology may exceed the differences between different technologies. Using synthetic hourly meteorological data of 5 sites from MeteoNorm in PVsyst, the annual specific yield of four technology groups of PV modules were simulated and compared. Overall, it is shown that the maximum differences as large as 7.34% in terms of PV module's specific yield are expected within same PV technology, which exceeds the maximum difference of 2.16% obtained for specific yields of different PV technologies. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) power generation can directly convert solar radiation photons into electrical energy, but PV panels produce a large amount of waste heat during absorption of solar radiation, significantly increasing the working temperature and reducing the photoelectric conversion efficiency of the panels. In this study, a phase-change material (PCM) is used to cool the PV panels, and fins are added to enhance PCM heat transfer. Using numerical simulation, the effects of fin spacing, fin height, solar radiation intensity, and ambient temperature on the heat-dissipation performance of the PV/PCM system were then studied. The fin–PV/PCM structure showed a good cooling effect. With decreasing fin spacing, the increase in the panel temperature gradually decreased. Fin spacing of 6 mm exhibited the best cooling effect, with the battery plate temperature reduced by 31.9 °C compared with that of the natural convection condition without fins. The increase in the panel temperature gradually decreased with increasing fin height, and the cooling effect of the panel improved significantly when the fin height was increased from 30 to 70 mm. The heat-dissipation effect of the fin–PV/PCM system was better with higher solar radiation intensity and higher ambient temperature. The results of this study will have important reference value for performance improvement of PV panels. [ABSTRACT FROM AUTHOR]