Long term behaviour of passively heated or cooled a-Si:H modules

We compare the outdoor performance of single junction a-Si:H PV-modules which were mounted in three different ways. One was thermally well isolated against convection and radiation losses in order to reach maximum operating temperatures. A second one was fixed onto a radiator to keep its temperature as close as possible to the air temperature. A third one served as a reference and was mounted with an open back side. The operating temperature of the modules could be strongly influenced by the different mountings. Although a high operating temperature results in a reduced VOC, it turned out to be beneficial for effective energy conversion in the long term due to a strongly reduced Staebler-Wronski degradation.