MEASUREMENTS OF THE EFFECTS OF NON-UNIFORM IRRADIANCE DISTRIBUTION ON STANDARD PV CELLS

摘要

Stationary parabolic trough systems with standard pv cells often exhibit low outputs compared to the theoretical optical efficiency. This is due to the non uniform irradiance distribution on the cells, which causes large resistive losses. In order to improve the output of the concentrators, it is important to understand and characterize this effect. Presented here are measurements of the effects of non uniform irradiance on the output of one monocrystalline and one polycrystalline Silicon cell. The influence of the width and position of the strip of high irradiance have been measured.We show that the width of the strip has a large impact on the fill factor and power output when the width is below 10-15 mm. The position of the strip of high irradiance is of lower importance, but the maximum power output is obtained when the strip is close to the busbar. These findings suggest that higher efficiencies can be obtained in new parabolic trough concentrators by widening the irradiance peak while maintaining the same total collected irradiation.