Effects of Highly Non-uniform Illumination Distribution on Electrical Performance of Solar Cells

Conventional thinking for cells under concentrated sunlight would suggest that short circuit current, and hence also open circuit voltage, can be determined exactly by the total illumination falling onto the cell. However with most concentrator systems the cells are exposed to highly focused light, with consequent non-uniform temperature and current distributions. Departures from the simple relationship are then observed. Starting from the current density – voltage relationship for any given cell position, a detailed examination is made of junction voltage and current as functions of position, and an overall cell I-V curve is produced for a given illumination distribution.