Optimal solar panel angle in Portland, OR
For a fixed rooftop installation in Portland, the weather-adjusted optimal angle is 36° tilt facing 210° SW. This generates approximately 1,551 kWh/m² per year. All numbers based on 2025 historical weather data.
| Textbook (clear sky) | Weather-adjusted | |
|---|---|---|
| Tilt | 41° | 36° |
| Azimuth | 180° S | 210° SW |
| Annual generation | 1,551 kWh/m² | |
What this means
The textbook formula says to tilt your panels at 41° and face due south (180°). But Portland's actual weather shifts the optimum to 36° tilt and 210° azimuth. The 30° westward azimuth shift is caused by morning cloud patterns that clear by afternoon.
These numbers are for a fixed-angle installation optimized across all 12 months. If you adjust your panels seasonally, you can gain an additional 3-5%. Read more in our seasonal adjustment analysis.
Run it for your exact address
This data is for Portland city center. Your roof may be in a slightly different microclimate. Our calculator optimizes for your exact coordinates.
Calculate Your Optimal Angle