Assessing the effect of variable atmospheric conditions on the performance of photovoltaic panels: A case study from the Vaal Triangle

The purpose of this paper is to present a practical setup which is used to determine the availability of power from a singular stationary photovoltaic panel for variable atmospheric conditions in the Vaal Triangle, located in southern Gauteng, South Africa. Atmospheric conditions in this paper are characterized by air pollution and cloud movements, both which impact negatively on the operation of photovoltaic panels as shown by a number of scientific studies. Power regulation is achieved through the use of a DC-DC converter with a constant load resistance being employed to ensure reliability of the results for repeated measurements. The performance of the system is determined by considering the amount of time in which the DC-DC converter delivers power to the load resistance over a one week period, given as a percentage. Initial results indicate that the performance of this system varies by as much as 26% over a three month period stretching from March through May of 2011.