Optimal year-round tilt angle ≈ your latitude. In winter, add 15°. In summer, subtract 15°.
At 40°N latitude: year-round optimal = 40°. Winter: 55°. Summer: 25°.
A fixed tilt at latitude × 0.87 minimizes annual energy loss vs. a single optimal fixed angle.
Reach for this calculator when a quick, verified engineering computation is needed without opening specialised software. The formula used follows the relevant standard and is documented for reference.
A frequent mistake is using nominal or rated values when actual measured values are required. Calculations based on nominal dimensions or catalogue specifications may not match field conditions — always use measured values where precision matters.
A mechanical engineer verifies a beam's deflection under a specified load using standard formulas. Running the calculation with exact dimensions confirms the design meets deflection limits before fabrication — catching an issue that would be expensive to correct in the field.
Equal to your latitude for best year-round output. Adjust +15° in winter, −15° in summer for seasonal optimization.