howmuchsun

Solar panel angle in Kakamega

Kakamega 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 89% facing south, 30° pitch
Best here facing south
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 Kakamega.

Percentage of maximum annual yield by roof orientation (rows) and pitch (columns).
Roof faces 15° 30° 45° 60° 90°
South 100% 97% 89% 76% 59% 32%
South-east / south-west 100% 98% 90% 80% 67% 43%
East / west 100% 98% 92% 84% 74% 52%
North-east / north-west 100% 97% 90% 80% 67% 43%
North 100% 97% 89% 76% 59% 32%

Where "tilt equals your latitude" happens to work

The rule of thumb says tilt your panels at your latitude — 0° for Kakamega. 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 yearsouth
Summersouth
Winter27°south
Flat on the ground

A flat installation here keeps 100% of the maximum; mounted vertically on a wall, 32%.

Other cities in Kenya

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