Solar Panel Angle in Seattle

Solar Panel Recommendations for Seattle

• Fixed mount: Set your panels at 44.5° tilt, facing South (180° azimuth).
• Seasonal adjustment: Tilt to 32.6° in summer and 62.6° in winter for up to 15% more annual energy.
• Monthly adjustment: Adjust tilt each month using the table above for maximum year-round production.

Making Solar Work in Seattle's Climate

Seattle receives approximately 3.5 peak sun hours daily — the lowest among major US cities. The Pacific Northwest climate produces dense cloud cover from November through March, with frequent rain and overcast conditions that severely limit winter production. However, Seattle's summer days are exceptionally long (16+ hours of daylight in June), generating strong production during peak daylight months.

Given Seattle's modest solar resource, maximizing system efficiency is critical. South-facing roofs with optimal tilt angles are important, and avoiding shading is essential. Seattle City Light and Puget Sound Energy offer net metering, and Washington's renewable portfolio standard supports solar adoption. While payback periods are longer than in sunnier locations, Seattle solar owners benefit from the region's high electricity rates.

Moss and algae growth on panels is a Seattle-specific concern due to the damp climate. Panels should be mounted at sufficient tilt to allow rain to naturally clean the surface, and periodic inspection for biological growth is recommended. Seattle's abundant evergreen trees create shading challenges that require careful site evaluation. Despite these factors, Seattle has an active solar community and many successful residential installations.

Orientation Performance

Panel orientation significantly affects energy production. The table below shows relative output compared to true south-facing panels:

Frequently Asked Questions

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