Visualizing "Soiling Loss" of Solar PV Panels

Campbell Scientific Japan K.K. has started offering the **"DustVue 10"**, a sensor that measures "panel soiling," a cause of power generation loss at solar power plants, with high accuracy.

Dust, pollen, and pollutants adhering to solar panels are a major cause of reduced power generation. The output loss due to soiling is considered to have the second-largest impact after the amount of sunlight, and this impact varies greatly depending on the season and environmental conditions. Therefore, accurately grasping the soiling loss and determining the appropriate cleaning timing is key to maximizing power generation efficiency.

The commonly used "two-panel comparison method" (comparing a clean panel and a soiled panel) is a standard method defined in the international PV performance monitoring standard (IEC61724-1), but it had the following issues:

- Difficulty in maintaining the clean-side panel (re-soiling, water spots, etc.) - Increased costs and variability due to manual cleaning - Errors due to differences between sensors - Difficulty in maintaining long-term accuracy

These were factors in increased operating costs and reduced data reliability.

The "DustVue 10" directly measures power generation loss by comparing a cell that gets dirty under the same environmental conditions as the power generation panel with a protected, clean reference cell. While following the principle of the conventional two-panel comparison method, it minimizes contamination by protecting the reference cell with a cover and exposing it only for a short time during measurement. With a reliable method compliant with IEC standards, it can grasp the loss due to soiling with an accuracy of ±1%.

Furthermore, an internal shutter automatically protects the reference cell, eliminating the need for frequent cleaning and water spraying facilities that were conventionally required, reducing the maintenance frequency to about once every six months to a year. It achieves stable data acquisition while significantly reducing the maintenance load.

The introduction of this product enables:

- Optimization of cleaning timing, reducing unnecessary cleaning costs - Quantification of soiling loss - Improved profitability by maximizing power generation

This directly contributes to improving the profitability of power producers, O&M providers, and cleaning companies.