Comparison of the Modes and Mechanisms of Degradation of Experimental c-Si PV Modules with Various Encapsulants

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PV Modules


Seven modules with different encapsulants, provided by the National Renewable Energy Laboratory (NREL), were installed at the Florida Solar Energy Center (FSEC) outdoor test facility for long-term durability testing in the hot and humid climate of Florida. Along with the modules, NREL also provided corresponding load resistors, junction boxes, and module connections. The modules were installed at latitude tilt, on a south facing rack on March 20, 2014.During project different types of tests such as visual inspection in environmental conditions and infrared imaging and I-V characterization were carried out on the seven modules: 110412-NRE-EVA, 110413-NRE-EVA-NC, 110413-NRE-TPU, 110420-NRE-TPO1 (2), 110512-NRE-PVB, 110628-NRE-ION and NRE-PDMS. Type of defects, origins of hot spots, cracks in the cell, browning/ discoloration occurring near the busbar/cell interconnect and the snail trails, and blistering were studied. I-V characteristics were obtained under the irradiance in the range of 950-1100 W/m2.Using the temperature and irradiance coefficients these measurements were normalized to standard test conditions (STC) conditions of 1000 W/m2 and 25 °C. The Raw Data Used for normalization was also given. Data closest to 40 °C was used, except for module NRE-PDMS in which the data at 1000 W/m2 and 50 °C was used.The data from these modules periodically monitored along with meteorological parameters.

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PV Modules

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