Off-Grid Solar Calculators

Solar panels

Solar Tilt Angle & Azimuth Estimator

A fixed array is rarely best at a tilt equal to latitude. A slightly shallower annual tilt usually beats a latitude-equals-tilt rule once you are past about 25°. Face true south in the northern hemisphere and true north in the southern hemisphere.

Inputs

Units
°

Positive in the northern hemisphere. Example: 40 for Denver, −33.9 for Sydney.

Terms of Service

Results

Please tick the box above to display the Result.

Engineering methodology

Annual fixed tilt is piecewise: 0.87 × |latitude| below about 25°, then Landau’s mid-latitude fit 0.76 × |latitude| + 3.1° at and above 25° (both clamped 0–90°). Landau published that fit for 25–50°; it is carried above 50° as well, because a latitude-equals-tilt branch jumps about 9° at the boundary and over-tilts northern Europe. Summer tilt ≈ |latitude| − 15°. Winter tilt ≈ |latitude| + 15°. Azimuth is 180° (true south) in the northern hemisphere and 0° (true north) in the southern hemisphere. Magnetic declination is not applied. This is a rule of thumb, not a sun-path or PVGIS yield study.

Frequently asked questions

Should solar panels face magnetic south or true south?

True south (azimuth 180°) in the northern hemisphere. A compass points to magnetic south/north; declination can be many degrees. This tool reports true azimuth only.

Is latitude-equals-tilt the best annual angle?

Not always. Above about 25° latitude, a slightly shallower annual tilt (Landau: 0.76×lat + 3.1°) usually beats a strict latitude tilt for year-round energy — near 52° that is roughly 43° rather than 52°. Roof pitch and snow shedding can override the number.

Why add 15° in winter and subtract 15° in summer?

The sun is lower in winter and higher in summer. The ±15° rule of thumb tracks that elevation. It is not a sun-path simulation and ignores shading and albedo.

More in this cluster

All tools in this cluster