Degradation of Output Characteristics of a Small Photovoltaic Module Due to Dirt Spots

This paper reports the output degradation characteristics of a small photovoltaic cell when a dirt spot adheres to the surface. The 11 W photovoltaic module GT434 was applied to various electric systems. The module consists of 34 cells, cut to 1/4 the silicon single crystal photovoltaic cell of a square with one side measuring 103 mm. The photovoltaic output power was found to be reduced by 50% when a 3% dirt area was applied to the small module. The decrease in output power was shown to improve when the shape of the photovoltaic cell was changed