Rain Not Enough: Pollen Reduces Solar Performance

• Discover how NREL and Solar Unsoiled are tackling the issue of pollen and bio-soiling on solar panels in the Southeastern US. A 10-year study finds that frequent rains are not enough to keep the panels clean and prevent financial losses.

A new study by the National Renewable Energy Laboratory (NREL) has found that rainfall is not enough to keep solar panels clean from pollen in certain parts of the US, particularly in the Southeastern states. Even after peak pollen season ended, the performance of the solar panels did not return to their previous levels due to frequent rains. The study showed that soiling potential must be carefully examined in regions with frequent rainfall and that planned cleaning may be necessary to avoid financial losses and lower performance. NREL and Solar Unsoiled are now designing a study to further investigate the mechanisms and risks associated with pollen and bio-soiling in the Southeastern US.

What Risks Does Pollen and Bio-Soiling Pose in the Southeast US?

• Pollen and bio-soiling can cause the photovoltaic cells in solar panels to become blocked, reducing the amount of energy the solar panel can produce.
• Pollen grains can reduce the efficiency of the cell by up to 15%, while bio-soiling can reduce efficiency by up to 40%.
• Pollen and bio-soiling can accumulate more quickly in wet climates, such as in the southeastern US, due to frequent rains, leading to reduced solar panel efficiency and performance.
• The build-up of pollen and bio-soiling on solar panels can cause corrosion, leading to long-term performance problems and potential financial losses.
• Solar Unsoiled is currently designing a study to investigate the mechanisms and risks associated with pollen and bio-soiling in the southeastern US.
• In order to reduce the risk of financial losses and lower performance, solar panel owners are advised to regularly clean their cells during peak pollen season and following heavy rains.