Assessing Dust Accumulation and its Impact on Solar PV Performance

Over the past three decades, photovoltaic (PV) technologies have significantly advanced, enhancing global power generation, particularly in regions with abundant solar irradiation. Bahrain, benefiting from high year-round solar exposure, is well-suited for PV systems. However, the harsh climatic conditions in the Middle East―such as high temperatures, dust, and pollution―adversely affect PV panel efficiency. Dust accumulation is a critical factor influencing performance and profitability, making it essential to address this issue for optimal functionality and returns. This research investigates how dust buildup impacts the power output of PV panels and aims to determine an economical cleaning frequency. A 31.2 kW solar PV system was installed on the rooftop of the University of Technology Bahrain for this purpose. The system consists of four rows, each generating equivalent power output. Data were collected over nine months to analyze the effects of different cleaning frequencies on power output degradation. The cleaning schedule included weekly cleaning for the first row, biweekly for the second row, every three weeks for the third row, and every four weeks for the fourth row. The fourth row remained uncleaned for 24 weeks to assess long-term effects. Results indicated that cleaning every two weeks resulted in a 2.11% decrease in output compared to weekly cleaning. Longer intervals led to greater declines; cleaning every three weeks caused a 3.4% drop, while every four weeks resulted in a 5.73% decrease. Extended uncleaned periods showed even more significant reductions in power generation, emphasizing that cleaning every two to three weeks is a practical and cost-effective maintenance strategy.