Abstract:
There are multiple environmental factors affecting the performance of a
photovoltaic (PV) module out of which soiling exponentially decreases the PV module
performance. The purpose of this study, therefore, has been dedicated towards
proposing a novel autonomous dust cleaning system for dusty conditions to mitigate
the effect of soiling on PV modules. A poly-crystalline module was tested for soiling
at three different tilt angles 21, 31 and 41 respectively. Consequently, the average
soil deposition at these each angle was 254 mg/m2
, 181 mg/m2 and 156 mg/m2 per day respectively and soiling caused power loss by 18.2%, 15.7% and 14.3%. The moving cleaning system in the experiment comprises of a moving part (horizontal bar) that moves across, spraying water over the PV module. The horizontal bar has flat fan nozzles installed in it, supporting the water spraying. The water sprayed over the PV module is collected in the storage tank and can then be reused. The process of cleaning utilizes 5.9 litres of water while 5.2 litres of water is recovered, cleaning a surface area of 40.256 m2. The power improvement post cleaning was 15.5%, 12.7% and 11.3% at each tilt angle. As a tandem effect of cleaning, cooling also occurred decreasing front PV module temperature by 1.2, 0.95, 0.70 and back PV module temperature 1.4,
1.1 and 1.2 at 21, 31 and 41 tilt angles respectively. The autonomous cleaning system is feasible for commercial sized PV systems after the financial evaluation.
