The latitude of a location primarily determines the optimal tilt angle for solar panels, while the direction (azimuth angle) is determined by the hemisphere. Here’s how latitude impacts solar panel orientation:
Direction (Azimuth Angle)
- Northern Hemisphere: Panels should face true south to maximize sunlight exposure.
- Southern Hemisphere: Panels should face true north for the same reason.
- Note: “True” south/north differs from magnetic compass directions. Correct for magnetic declination (varies by location).
Tilt Angle (Elevation)
Latitude is the baseline for setting panel tilt:
- General rule: Tilt panels at an angle equal to your latitude (e.g., 34° in Los Angeles, 41° in NYC).
- Seasonal adjustments:
- Winter: Latitude + 15° to capture low-hanging sun.
- Summer: Latitude – 15° to align with higher sun.
- Spring/Fall: Latitude ± 0°.
- Exceptions:
- Near the equator (low latitude), panels perform well at flatter angles (10–20°).
- At higher latitudes (e.g., 45–50°), steeper angles (~40–50°) are ideal.
Why Latitude Matters
- Sun path: The sun’s elevation varies with latitude. Lower latitudes (closer to the equator) experience higher solar angles, while higher latitudes see lower angles.
- Cloud cover: In regions with frequent clouds, slightly flatter angles (~latitude – 5–10°) can capture diffuse sunlight better.
Efficiency Impact
- Direction priority: South-facing (northern hemisphere) panels can produce ~30% more energy than non-optimal orientations.
- Tilt vs. latitude mismatch: A 20° deviation from the optimal tilt reduces output by 7–9% (e.g., Portland, OR, loses more than Phoenix, AZ).
For precise calculations, tools like PVWatts or Aurora Solar factor in latitude, local weather, and shading.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-does-the-latitude-of-a-location-impact-the-direction-solar-panels-should-face/
