Performance Simulation for an Amorphous Silicon Solar Cell
Rasool R. Attab
In this study the effect of the thickness of active layers constituting the solar cell and the operating temperature on the working properties of solar cells composed of hydrogenated amorphous silicon (a-SiC:H) was investigated using simulation-based theoretical processing. The equations for calculating the open-circuit voltage, short circuit current, fill factor, maximum power point, and shunt efficiency are also employed.
A solar cell exhibits two types of temperature dependence: one on conversion efficiency, and the other on light-induced decay, where it turned out that the studied solar cells maintained a higher generation capacity than other cells, even after long periods of working under environmental conditions. For the temperature ranging from below room temperature to the boiling point the results show the advantage of using this type of cell due to its suitability for practical use, especially in the high-temperature regions represented by East Asian countries.
Amorphous hydrogenated silicon (a-SiC:H), a part from being an auspicious material for converting solar energy into electricity, generally shows a poor efficiency (about 4-6%). This low efficiency is due to the short diffusion lengths (about 0.1 μm). In this research, we studied the performance of solar cells as it was found that the poor efficiency is primarily due to the design which leads to an excessive optical impedance losses. The study showed that there is an optimal thickness to be used and that there are simple techniques that will increase the efficiency such as the double-pass of photons that can lead to a significant increase in the density of charge carriers. It turns out that the design can lead to a substantial increase in efficiency to about 9-15%.
Keywords: silicone solar cell, single diode model, environment effect, temperature affect, energy generation, fill factor, solar efficiency