The Impact of Dust on the Power Generation of Off-Grid Solar PV Systems

Photovoltaic arrays are used in outdoor environments, and the atmospheric environment is full of various forms of dust particles.The dust settled on the surface of photovoltaic components, on the one hand, will block sunlight, reduce the transmittance of the glass surface of photovoltaic components, thus reducing the amount of solar radiation reaching the surface of the cells; on the other hand, it will lead to a change in the form of heat transfer on the product surface. The dust absorbs solar radiation and converts it into its own thermal energy, while also blocking the external heat dissipation of the photovoltaic module cover glass. In summary, dust is one of the main problems affecting the performance ratio of photovoltaic power stations.

The impact of dust on off-grid solar PV systems' solar radiation

Dust on the surface of the glass not only severely affects the transmittance of solar radiation but also causes a significant increase in diffuse reflection of solar radiation reaching the surface of the off-grid solar PV system components due to surface dust. According to experimental measurements, dust accumulated on the glass surface can lead to a solar radiation loss of 5%-30％, mainly due to the absorption, reflection, andscattering of solar radiation by the dust adhering to the glass surface.

The impact of dust calcification deposits on off-grid solar PV systems' light transmission

Dust contains a large amount of calcium and magnesium oxides. When dust on the surface of photovoltaic components encounters rainfall, a small amount of calcium and magnesium ions will dissolve into the rainwater and then reattach to the glass surface of the off-grid solar PV system components. If not cleaned in time, over time, a thick and hard layer of calcium and magnesium scale will form on the surface of photovoltaic components. Once scale forms, it's not easy to remove and will severely affect the power generation effect of photovoltaic components, and in severe cases, may even cause some photovoltaic cells to have hot spots and other problems.

The impact of dust on off-grid solar PV systems component temperature

Dust adhered to the tempered glass surface causes a portion of solar radiation to be absorbed by the dust and converted into heat energy, thereby increasing the working temperature of photovoltaic components. At the same time, due to the dust on the component surface, there will also be a temperature-retaining effect on the surface of photovoltaic components, affecting the heat dissipation of the components and further increasing the thermal temperature effect of photovoltaic components, which affects the power generation effect of photovoltaics.

As the power-generating component of an off-grid solar PV system, photovoltaic components are the core unit of the entire off-grid solar PV system. The photoelectric conversion efficiency of photovoltaic components is inversely proportional to temperature, and the photovoltaic efficiency of the components will decrease as the temperature rises. Since the dust attached to the surface of the components absorbs a part of the heat energy, the internal temperature of the solar panel is easily increased through heat transfer, reducing photovoltaic efficiency.

In off-grid solar PV systems, surface dust not only affects the solar radiation reaching the photovoltaic cell surface but also increases the temperature rise of photovoltaic components. If the dust on the glass surface is not cleaned in time, it will greatly affect the power generation performance of photovoltaic components. And, under certain thicknesses of dust accumulation, the larger the angle of sunlight incidence, the longer the path of sunlight through the dust layer, making it easier for reflection, scattering, and absorption phenomena to occur. Therefore, in the maintenance of photovoltaics, special attention should be paid to the impact of surface dust on photovoltaic power generation, clean timely to keep the photovoltaic components' surface clean, allowing for the efficient operation of the power station.

Andy Cao

I’m Andy Cao, an energy engineer with over 16 years of hands-on experience in solar inverters, lithium battery energy storage, photovoltaic systems, and solar street lighting. I focus on real-world system performance and write to share practical, experience-based insights for professionals working in the solar energy industry.