- Study finds power losses exceeding 50% in fly ash contaminated photovoltaic modules during peak sunlight hours.
- Predictive model shows near perfect agreement with experimental results with correlation of 0.997 and accuracy above 0.99.
- Findings highlight urgent need for improved cleaning and mitigation strategies in polluted urban and industrial solar markets.
A new study conducted in Morocco titled ‘Quantitative assessment of fly ash–induced soiling in photovoltaics: Experimental validation and predictive modelling,’ has quantified how fly ash pollution from industrial, vehicular and residential combustion processes significantly degrades solar energy generation in urban environments. The research shows that fine particulate matter settling on solar panels reduces light transmission, increases thermal effects and ultimately lowers electricity output.
The study combined controlled experiments with numerical modelling to assess how fly ash accumulation affects photovoltaic modules. Results show an exceptionally strong match between measured and simulated performance, with a Pearson correlation coefficient of 0.997 and a coefficient of determination of 0.994. Model error remained low, with a root mean square error of 0.79 degrees Celsius and a mean absolute error of 0.62 degrees Celsius, confirming high predictive reliability for soiling induced performance losses.
Findings further demonstrate that fly ash acts as both an optical barrier and a thermal modifier on module surfaces. While the deposited layer reduces heat transfer across the module structure and produces a measurable drop in operating temperature, it simultaneously drives significant electrical losses due to reduced light availability for the silicon cells.
Power output analysis showed reductions exceeding 50 percent on average for soiled panels, particularly during peak solar irradiation between 10:00 and 14:00. Spectral testing revealed that fly ash exhibits high absorbance of up to 0.8 across the ultraviolet and visible range, significantly limiting incoming photon energy. In addition, low transmittance further restricts light penetration to the active layer, while reflectance levels exceeding 35 percent in the infrared range increase photon losses.
The results underline that optically active airborne particulates such as fly ash represent a major and often underestimated driver of photovoltaic performance decline in polluted regions. The study concludes that effective cleaning regimes and preventive surface protection strategies are essential to maintain reliable solar generation in high emission urban and industrial environments.
Link to the full paper HERE
Author: Bryan Groenendaal
