In the photovoltaic industry, there have been reports of performance losses in solar modules with Topcon technologies due to UV radiation shortly after initial operation. To evaluate these claims, scientists at the Fraunhofer Institute for Solar Energy Systems analysed common UV tests on the modules and assessed the validity of the test methods.
Recovery is possible
The result: conventional UV tests usually rate the degradation of Topcon modules significantly higher than the actual drop in performance. This is because the modules may recover under certain circumstances.
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High dosesseveral times
The researchers exposed the modules to a high UV dose in the ISE laboratory and then stored them in the dark. Subsequent performance tests actually showed a reduction in performance. After a certain period of time, the modules were exposed to sunlight again. These tests showed a clear recovery effect.
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Lower losses than assumed
The researchers also applied this test procedure to modules in solar parks. Here, they identified a number of differences. For example, in some modules they observed very little degradation after the UV test. However, other modules showed a decline in performance of up to 5%. (su)
