Dust Accumulation and its Effect on Solar Photovoltaic Output: An Experimental Study in Bahrain

The demand for energy is constantly increasing, and with environmental concerns, using sustainable and clean energy sources has become essential. Photovoltaic (PV) solar systems represent a substantial contribution towards developing a more sustainable energy system, but their performance is affected by low efficiency, environmental factors, and installation factors. Dust accumulation on the surface of solar panels is inevitable and is one of the essential parameters that affect PV panel performance, yield, and profitability. This accumulation can reduce solar irradiance and ultimately result in lower energy production. However, the dust characteristics - such as its composition, size, shape, and local weather conditions - vary depending on the geographical location. Most users clean PV panels manually with water, with fewer using automated cleaning systems, which are expensive and increase the cost of the system and production costs. Many investigators have studied various techniques for cleaning and preventing dust buildup on solar panels. This study aims to investigate the effect of dust deposition on PV panel generation and determine the most optimal and cost-effective cleaning schedule. A 32 kW PV panel system, divided into four parallel rows of equal power generation, was installed on the rooftop of the University of Technology Bahrain (UTB) building. The rows were cleaned in succession every week, two weeks, three weeks, and four weeks, respectively. The study lasted for four months, and the data were statistically analyzed. The results show that dust deposition reduces the efficiency of the solar PV panels, cleaning the panel after two weeks drops an efficiency of 2.3%; cleaning the panel after three weeks drops an efficiency of 3.5%; and cleaning the panel after four weeks drops an efficiency of 7.1%, with dust deposition density of 4.54% was measured over a four-week period. Moreover, a test of difference on the DC cumulative energy (KWh) of the four sets of panels was analyzed. The results reveal that cleaning the panels every two to three weeks is a practical and cost-effective option, however cleaning them every three weeks is a very good option and highly recommended.