Solar Panel Angle Calculator

How This Tool Works

This calculator determines optimal solar panel tilt angle based on your location's latitude and desired optimization (year-round, seasonal). The fundamental rule is that the optimal angle for fixed installations equals your latitude. This provides the best balance across all seasons, maximizing annual energy production.

For seasonal optimization, the calculator adjusts: Summer angle = latitude - 15° (because the sun is higher in the sky), Winter angle = latitude + 15° (because the sun is lower). These adjustments account for the sun's changing position throughout the year. Adjustable mounts that can change angle seasonally can increase efficiency by 10-25% compared to fixed mounts.

Solar Panel Angle Guidelines

• Year-Round Fixed: Angle = Latitude (best compromise for all seasons)
• Summer Maximum: Angle = Latitude - 15° (optimizes May-August production)
• Winter Maximum: Angle = Latitude + 15° (optimizes November-February production)
• Spring/Fall: Angle = Latitude (optimal for March-April, September-October)
• Adjustable Mounts: Change angle seasonally for 10-25% efficiency gain
• Mobile/RV: Use latitude angle or 30-45° practical compromise
• Direction: Face true south (Northern Hemisphere) or true north (Southern Hemisphere)

Installation Tips

• Find True Direction: Use compass app with magnetic declination correction, or use sun position
• Account for Shading: Avoid shadows from trees, buildings, or other panels
• Consider Roof Pitch: If roof angle is close to optimal, mounting flat to roof may be acceptable
• Wind Load: Steeper angles may increase wind load - check local building codes
• Snow Shedding: Steeper angles help snow slide off in winter climates
• Maintenance Access: Ensure angle allows for cleaning and maintenance
• Mobile Installations: Consider adjustable mounts for flexibility when parked
• Professional Installation: For home systems, consult with solar installer for optimal setup

FAQ

• What is the optimal angle for solar panels?
  The optimal angle for fixed solar panels is approximately equal to your latitude. For example, at 40° latitude, the optimal year-round angle is about 40°. This provides the best balance across all seasons. For maximum efficiency in specific seasons: Summer = latitude - 15° (sun is higher), Winter = latitude + 15° (sun is lower). Adjustable mounts allow you to optimize for each season.
• How do I find my latitude?
  Find your latitude using: Google Maps (right-click location, see coordinates), GPS device, online latitude finder tools, or city reference (most cities list approximate latitude). Latitude ranges from -90° (South Pole) to +90° (North Pole). Northern Hemisphere uses positive values, Southern Hemisphere uses negative. The calculator includes quick-select buttons for common cities.
• Should I adjust solar panel angle seasonally?
  Adjustable mounts can increase efficiency by 10-25% compared to fixed mounts. For maximum summer production: use latitude - 15°. For maximum winter production: use latitude + 15°. For year-round fixed installations: use latitude angle. If you can only adjust twice per year: use latitude - 10° for summer (Apr-Sep) and latitude + 10° for winter (Oct-Mar). Many RV/van installations use fixed mounts for simplicity.
• What direction should solar panels face?
  Solar panels should face true south in the Northern Hemisphere and true north in the Southern Hemisphere for maximum sun exposure. Magnetic compass directions differ from true directions - account for magnetic declination (typically 5-15° depending on location). For mobile/RV installations, park facing the optimal direction when possible. East/west facing panels produce 15-20% less than south-facing.
• How does angle affect solar panel efficiency?
  Solar panel efficiency decreases as the angle deviates from optimal. At 15° deviation: ~5% efficiency loss. At 30° deviation: ~15% efficiency loss. At 45° deviation: ~30% efficiency loss. Flat panels (0°) work but lose 20-40% efficiency depending on latitude. Vertical panels (90°) are very inefficient except in polar regions. The optimal angle maximizes direct sunlight throughout the day.
• What angle should I use for RV or van solar panels?
  For RV/van installations: Fixed mounts typically use latitude angle (year-round compromise). Adjustable mounts can optimize seasonally. Consider roof curvature and available mounting space. Some installers use 30-45° as a practical compromise for mobile installations. For maximum flexibility, use adjustable mounts that can tilt 0-60°. Remember that mobile installations may not always face optimal direction, so angle is less critical than fixed home installations.