"Full-, half-, and quarter-size CdS thin-film solar cells were subjected to a simulated space environment to test the effect of cell size on performance degradation. The test data indicate that there is more variation in degradation among common size cells than between different size cells and that cell degradation does not appear to be substantially affected by cell size." -- Title page.

Thin-film Cu2S-CdS solar cells, loaded at various fixed values of load resistance, were thermally cycled for 1429 cycles in a simulated space environment. Cell performance was measured under controlled conditions in air before and after thermal cycling. These data were used to determine the effect of load voltage on cell performance. The performance of the cells was relatively independent of load voltage up to about 0.39 volt. This appears to be a threshold voltage, beyond which there was a significant loss in cell performance. Fortunately, this threshold voltage appears to be sufficiently higher than the maximum power voltage of 0.33 volt so that it can be avoided in most applications.