howmuchsun

Solar panel angle in Faaa

In Faaa, fixed panels collect the most energy over a year tilted 16° from horizontal and facing north. But anything between 5° and 25° is within 2% of the best, so the pitch you already have is probably fine.

What is your roof worth?

Of the maximum 98% facing north, 30° pitch
Best here 16° facing north
Good-enough range 5–25° within 2% of the maximum

Every roof, scored

Percentage of the maximum possible annual yield, for each combination of orientation and pitch in Faaa.

Percentage of maximum annual yield by roof orientation (rows) and pitch (columns).
Roof faces 15° 30° 45° 60° 90°
North 97% 100% 98% 90% 77% 45%
North-east / north-west 97% 98% 95% 88% 77% 51%
East / west 97% 95% 89% 80% 70% 49%
South-east / south-west 97% 90% 80% 67% 55% 35%
South 97% 89% 75% 59% 44% 23%

Why "tilt equals your latitude" is wrong here

The rule of thumb says tilt your panels at your latitude — 18° for Faaa. The real optimum is 16°, 2° lower than the rule suggests.

Two reasons, both geometric. Summer days are much longer than winter ones, so the year's energy is weighted toward a higher sun than the annual average. And a low winter sun sends its light through a long slant of atmosphere, arriving weak — tilting to catch it costs more in summer than it wins in winter.

In fairness to the rule: following it here would cost you only 0.0%. It is wrong, but it is not expensive.

Seasonal angles

If you can adjust your panels twice a year, these are the angles to use. Most people should not bother — the gain is small and the ladder is real.

SettingTiltFacing
Fixed, all year16°north
Summernorth
Winter42°north
Flat on the ground

A flat installation here keeps 97% of the maximum; mounted vertically on a wall, 45%.

Assumptions

  • These are angles and percentages, never kilowatt-hours. Optimal angles are driven by geometry and are robust. Absolute energy output depends on measured irradiance, cloud, soiling and hardware, none of which are modelled here.
  • Clear sky, no shading. Trees, chimneys, neighbouring buildings and terrain are ignored, and they can dominate everything on this page.
  • Fixed panels. Trackers follow the sun and change the answer entirely.
  • Ordinary ground. Reflectance is taken as 0.2, typical for grass and soil. Snow reflects far more and favours steeper tilts.

Full methodology, sources and known limitations