Researchers from the Fraunhofer ISE have combined indoor and outdoor tests to understand and quantify degradation processes in Topcon sun panels. The new method is intended to provide data for validating and improving stress laboratory protocols.
A research team of the Fraunhofer Institute for Solar Energy Systems (Fraunhofer ISE) of Germany has accelerated laboratory aging combined with extra exposure to improve the assessment of the reliability of the Topcon sun module.
The new method is intended to provide data for validating and improving stress laboratory protocols. “By comparing the evolution of lab-induced damage under real outside conditions with well-known phenomena in the field, it could validate that these individual laboratory tests are effectively focusing on field-relevant failure modes and accurately reflect their potential severity,” the scientists emphasized.
In the newspaper “Combination of indoor and outdoor measurements for the identification of degradation trends in PV modules“Published in RRL SolarThe researchers explained that one of the most important goals of their work was to understand or accelerate or delay specific breakdown symptoms that are observed in interior environments.
With the proposed approach they tested six commercially available photovoltaic modules, three of which are based on Topcon technology, two were designed with a heterojunction (HJT) architecture and one was based on perccelles. Their power varied from 391. W to 571.5 W. The names of the manufacturers were not announced.
The testing was carried out for approximately eight months, whereby the IV curves were constantly checked and kept on maximum power point (MPP). Indoor Characterization measurements were taken for all modules before and after the accelerated aging.
Image: Fraunhofer Isee, RRL Solar, CC by 4.0
The outside tests were performed at the Fraunhofer Ise monitoring station in Mersingen, southern Germany, where all modules are tilted at 30 ° with an orientation on the south. “IV -curve measurements are filtered in radiation ranging between 775 and 825 Wm-2With radiation and temperature fluctuations during the acquisition of the curve that was kept less than 1% for stable state conditions, “the research group said.
The analysis showed that both top-cone and HJT modules are susceptible to the penetration of moisture, whereby the short-circuit current is affected, which is attributed by the scientists to be due to damage to the incoming layer or changes in the optical properties.
They also revealed that the highest demolition percentages were observed in a topcon module encapsulated with polyoleefinelastomers (POE), namely 3% in the laboratory and 9.75% after 8 months of exposure on the test field. “This suggests that even in the absence of acetic acid for POE, other factors, such as non-optimal lamining processing that releases residues or reactive species, polymer additives or solder flux, still contribute to moisture sensitivity and corrosion,” they explained further.
The outdoor tests also showed that the Topcon modules are vulnerable to UV-induced demolition, although this turned out to be in accordance with laboratory observations.
“The results suggest that standard IEC tests, although valuable, may not fully catch the complexity of field breakdown,” the scientists concluded. “A combination of indoor and outdoor evaluations can further determine the demolition risks, which improves the general reliability of these advanced technologies and will be further developed.”
This content is protected by copyright and may not be reused. If you want to work with us and reuse part of our content, please contact: editors@pv-magazine.com.
Popular content
