Washington (WA)
How dirt and soiling reduce your solar output in Washington
Panel soiling — the accumulation of dust, pollen, bird droppings, and other debris — is one of the most common and fixable causes of solar energy loss. In arid regions, soiling alone can reduce output by 5–15%. Here's what you should know.
How Washington's climate affects this issue
Regular rainfall helps manage soiling naturally, though pollen, bird droppings, and mineral deposits still accumulate.
Climate
temperate
Sun hours
3.4 hrs/day
Soiling risk
low
Solar adoption
moderate
Related issues
Panel soiling
Dust, pollen, bird droppings, or debris accumulation reducing light absorption. More severe in arid or agricultural areas.
Typical loss: 2–15%
Self-check tip:
Visually inspect panels from ground level. If you can see a visible film or debris, cleaning may restore 2–7% production.
Check your Washington solar system
Use our free Solar Loss Checker to estimate how much energy your system in Washington may be losing.
Check my systemBased on conservative solar performance modelling and published degradation data
Updated April 2026 · Structured performance modelling
How we calculate →