The Effect of Water Vapor on the Performance of Solar Cells

The objective of this study is to determine the effect of variations in global spectral distribution due to the variation of water vapor on the performance of two types of solar cells, nanocrystalline silicon (nc-Si:H) and cadmium telluride (CdTe) using the spectral irradiance model for clear skies SMARTS2 over a typical rural environment in Setif. Water vapor can reduce the amount of sunlight reaching a solar cell, and thereby cause a reduction in the electrical current, fill factor, open circuit voltage. The results indicate that water vapor increase in the atmosphere reduces the short circuit current of the CdTe cell by 3.15% while this reduction is about 2.38% for the (nc-Si:H) cell. The efficiency for both cells increases with increasing water vapor. These findings should be taken into consideration by solar cell engineers for better sizing of these types of solar cells.