howmuchsun

Solar panel angle in Port-Gentil

Port-Gentil sits close enough to the equator that panels collect most energy lying almost flat — the best tilt is just . At that angle the direction they face barely matters, which is a luxury almost nowhere else has. Anything up to 10° stays within 2% of the maximum.

What is your roof worth?

Of the maximum 90% facing north, 30° pitch
Best here facing north
Good-enough range 0–10° within 2% of the maximum

Every roof, scored

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

Percentage of maximum annual yield by roof orientation (rows) and pitch (columns).
Roof faces 15° 30° 45° 60° 90°
North 100% 97% 90% 77% 61% 33%
North-east / north-west 100% 98% 90% 80% 67% 42%
East / west 100% 98% 91% 82% 71% 49%
South-east / south-west 100% 97% 90% 79% 66% 41%
South 100% 97% 89% 76% 60% 33%

Where "tilt equals your latitude" happens to work

The rule of thumb says tilt your panels at your latitude — 1° for Port-Gentil. The real optimum is , so here the rule happens to be about right.

The rule breaks down further from the equator, where the optimum falls increasingly below the latitude — by around 10 degrees at 50°, and 15 by 65°. Close to the equator the two happen to coincide, so here the rule of thumb is genuinely fine.

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 yearnorth
Summernorth
Winter26°north
Flat on the ground

A flat installation here keeps 100% of the maximum; mounted vertically on a wall, 33%.

Other cities in Gabon

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