Investigation on particle deposition criterion and dust accumulation impact on solar PV module performance

Investigating the particle deposition mechanism on the solar PV module surfaces is beneficial to predict the dust accumulation amount and formulate the dust cleaning scheme. This study comprehensively analyzed the particles mechanical behavior in the movement and collision process with the module surfaces. Then, the energy-based particle deposition criterion was proposed and a dust accumulation numerical model under the experiment condition was established. Comparing the simulation and experimental results verified the rationality of particle deposition criterion and simulation method. Based on this, the effects of wind speed, humidity, and particle size on the dust accumulation characteristics of PV modules were simulated. Moreover, the dust accumulation impact on PV performance was predicted. The results showed the dust accumulation amount presents a greater effect on PV transmittance than efficiency. Furthermore, the dust accumulation decreases first and then increases with increasing wind speed, and the minimum occurs at 3 m/s, approximately 1.45 g/m2. However, the dust accumulation increases approximately linear with increasing humidity. Additionally, the dust accumulation amount displays a negative correlation with particle size under 30% humidity, and when particle size increases from 10 μm to 30 μm, the dust accumulation decrease from 9.76 g/m2 to 2.59 g/m2 at 1 m/s, resulting in the reduction of PV efficiency reduces from 14.64% to 3.89% and the transmittance reduction decreases from 25.32% to 8.38%. In future research, developing a specific self-cleaning coating to prevent the deposition of 10 μm particles is conducive to improve the PV efficiency and transmittance while reducing the dust accumulation.