1. Hazards of dust accumulation

If there is accumulated water and dust on the lower edge of photovoltaic modules, it will reduce power generation and may also generate heat spots, affecting the service life of the modules. Many industrial and commercial rooftop photovoltaics have encountered the problem of low angle dust accumulation on the lower edge, resulting in a loss of over 4% of annual power generation.

1.1. Reduce component power generation

The reflection and blocking of some light along the mud strip below the component reduces the radiation received by the battery cells in this area, resulting in a decrease in the current and potential generated by the battery cells in this area. As most of the battery cells in the component are connected in series, the cells from adjacent cells flow into this area, which is actually similar to the heating resistance, affecting the power generation of the entire component.

1.2 Generating Hot Spots

The radiation received by the battery cells along the mudband area under the component is relatively less than that of other non mudband areas, and the results generated are similar to local shadow occlusion, that is, the current generated in this area is less than that in other non mudband areas, and may lead to the formation of heat spots. (see figure below)

1.3. Oxidation of AR antireflection film to form rainbow bands (rainbow stripes)

Photovoltaic glass is prone to hydrolysis under high temperature and humidity conditions. The generated sodium hydroxide corrodes the coating layer on the glass surface, and the generated silicic acid condenses and adheres to the glass surface. At the same time, ultraviolet radiation has a significant destructive effect on some ion bonds of the substances in the coating. The two factors simultaneously intensify the physical changes of the film layer in the water and dust accumulation areas, forming a "rainbow pattern"