Solar Panel Angle Guide
Solar Panel Angle in Seattle
locationPage.latitudeLineHere's the optimal solar panel tilt and orientation for maximum energy production.
Year-Round Tilt
44.5°
Summer Tilt
32.6°
Winter Tilt
62.6°
Face
South
180° azimuth
Monthly Optimal Tilts for Seattle
Jan
60.0°
Ideal: 67.9°
Feb
59.3°
Mar
47.6°
Apr
35.9°
May
27.3°
Jun
24.2°
Jul
27.3°
Aug
35.9°
Sep
47.6°
Oct
59.3°
Nov
60.0°
Ideal: 67.9°
Dec
60.0°
Ideal: 71.1°
Peak Sun Hours
3.5 hrs/day
Average daily solar insolation
Annual Production (400W panel)
~511 kWh
At 44.5° tilt, facing South
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 long summer days (16 hours of daylight in June) generate strong summer output.
Seattle City Light and Puget Sound Energy offer net metering, and Washington state has a renewable portfolio standard supporting solar growth. Washington also offers a sales tax exemption for solar equipment. These policies help offset the region's modest solar resource.
Moss growth on panels is a specific concern in Seattle's damp climate. Regular cleaning may be needed for panels with low tilt angles. Tree shading from the region's abundant evergreens requires careful site assessment. Seattle's hilly topography means roof orientation varies significantly by neighborhood.
Orientation Performance
Panel orientation significantly affects energy production. The table below shows relative output compared to true south-facing panels:
| Orientation | Relative Output |
|---|---|
| South | 100% |
| Southeast | 96% |
| Southwest | 96% |
| East | 85-90% |
| West | 85-90% |
| North | 60-75% |
Frequently Asked Questions
Does Seattle get enough sun for solar?
Seattle has the lowest solar resource of any major US city (~3.5 peak sun hours). Long summer days help, and Washington's renewable incentives make solar worthwhile.
How much energy can a 400W panel generate here?
With 3.5 peak sun hours per day, a properly aligned 400W panel could generate approximately 511 kWh per year.
Related Calculators
Solar Panel Tilt Calculator
Calculate optimal tilt for any latitude and month
Solar Panel Azimuth Calculator
Find the exact compass heading for your panels
Get precision alignment with SolarAlign Pro
Use your phone's sensors to align your panels to the exact angle calculated here.Learn more →