Effects of Dust on PV
Numerous studies and experiments have shown that dust deposited on a solar panel surface will block incoming solar rays and as a result will reduce the solar energy output, when compared to a clean panel. There are many factors, including relative humidity and particle size, that will contribute to the quantity of light particles blocked by the dust. From studies conducted in Perth, it was found that dusty panels’ monthly power production dropped by an average of 4.5%.
The impacts of dust on a solar array’s overall output of energy, and hence revenue, becomes more significant as the array size increases. For example, a 1MW array exposed to 8 hours of sunlight daily generates an average of 8800 kWh per day, totalling around 3200 MWh annually. However, even a 4.5% loss due to dust and debris can lead to a significant shortfall, equating to approximately 144,000 kWh of lost energy. In financial terms, this equates to a loss of over $40,000 due to dust alone, based on the Synergy A1 tariff as a benchmark for energy pricing. Thus, the effects of dust and debris result in a significant waste of energy and money.
Manual Cleaning
Manually cleaning PV modules is dangerous and has resulted in many worker deaths and injuries in Australia. It is fraught with insurance and OH&S risks while providing minimal increase in PV module performance. Aside from the risks to the contractor, there is a high risk of damage to your solar array. Rough handling, uneven weight distribution, or excessive force applied to a PV module can cause microfractures that are invisible to the naked eye. Once a module sustains microfractures, its output performance begins to diminish. These microfractures grow and further shorten the module’s lifespan. In addition to the safety concerns and potential damage to PV modules, manual cleaning of large arrays also entails significant costs and time investments. Cleaning the array with water can leave hard water scale residue on the panels, damaging the cells and lowering their long-term efficiency.
Automated Cleaning
Greenleap’s LOTUS-A4000, is a fully-autonomous and waterless solar panel cleaning robot. It is the ultimate solution to clean and maintain solar plants operating in harsh and arid regions. The robot has microfiber cleaning fins that provide airflow and a controlled impact when the cleaning arm spins over the PV module’s surface, flicking off dust particles from the panels without dragging or damaging them. This gentle and repetitive flicking action removes 98% of foreign particles on the first sweep across the array.
Benefits
Solar panel cleaning robots provide numerous benefits to solar facility operators. Firstly, they contribute to an increased energy output by ensuring that the solar panels are clear of dust and debris, which will maximise the solar absorption capacity. Concomitantly, maintenance costs are significantly reduced as they eliminate the need for manual cleaning operations, saving both time and labour expenses. Additionally, the use of autonomous robots enhances safety for workers by minimizing the need for them to access dangerous environments, such as climbing onto rooftops or navigating large solar arrays. Furthermore, the even weight distribution of these robots ensures that the panels are maintained without risking damage or fractures, prolonging their lifespan and minimizing the need for costly replacements. Lastly, the adoption of waterless cleaning technology by these robots contributes to environmental conservation by reducing water consumption and eliminating the release of wastewater, thereby minimizing the ecological footprint.
References
Arthur J. Gallagher & Co. (2024). Micro-Fractures in Solar Modules: Causes, Detection and Prevention. Retrieved from News & Insights: https://www.ajg.com/us/news-and-insights/2020/jan/micro-fractures-in-solar-modules-causes-detection-and-prevention/
Bureau of Meterology. (2024). Average annual and monthly sunshine hours. Retrieved from Australian Government: http://www.bom.gov.au/climate/maps/averages/sunshine-hours/?period=an
Du, X. (2019). Turbulent airflow dust particle removal from solar panel surface: Analysis and experiment. Journal of Aerosol Science Volume 130, 32-44.
Lasfar, S. (2021). Study of the influence of dust deposits on photovoltaic solar panels: Case of Nouakchott. Energy for Sustainable Development Volume 63, 7-15.
Synergy. (2024). Synergy Home Plan (A1) tariff. Retrieved from Energy Plans: https://www.synergy.net.au/Your-home/Energy-plans/Home-Plan-A1
Tanesab, J. (2018). Energy and economic losses caused by dust on residential photovoltaic (PV) systems deployed in different climate areas. Renewable Energy Volume 120, 401-412.