Computer analysis of resistance and non-uniform illumination effects on concentrator solar cells

A computer program has been developed to perform a two-dimensional matrix analysis of the voltage distribution in the top layer of concentrator solar cells in order to evaluate the important effects of top layer sheet resistance, contact grid geometry, and non-uniform illumination. The uniformity of illumination influences the cell efficiency through modifying the resistance losses in the cells. It is shown that introduction of lower top layer resistance (∼ 5 ohms/square) reduces the sensitivity of cell performance to illumination uniformity, which suggests important economic benefits for concentrator systems: reduced power loss (higher conversion efficiency) in solar cells at higher concentrations, and relaxed tolerances on illumination uniformity (lower concentrator cost).