Location data · North Rhine-Westphalia
Sun hours in Ahlen
How sunny is Ahlen? Over a year the sun delivers 1,304 kilowatt-hours onto every square metre here — in June roughly 5 times as much per day as in December. “Sun hours” has two meanings: the weather report counts how long the sun shines. For solar power what matters is how much energy arrives — and that is what this page shows, as peak sun hours (hours of full sun power).
For solar planning this means: an optimally tilted, south-facing array (35°) harvests an annual average of 3.57 peak sun hours per day in Ahlen. In 9 out of 10 years at least 1,216 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.
- Annual average (PSH)
- 3.57 kWh/m²/d
- P90 annual total
- 1,216 kWh/m²
- Optimal tilt
- 40°
- Terrain horizon max.
- 1.1°
Sun hours per month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PSH/day (35° south) | 1.24 | 2.19 | 3.59 | 4.90 | 5.29 | 5.57 | 5.32 | 4.91 | 4.17 | 2.82 | 1.69 | 1.11 |
| P90 | 0.92 | 1.62 | 2.87 | 4.09 | 4.45 | 4.81 | 4.66 | 4.38 | 3.63 | 2.26 | 1.25 | 0.80 |
Daily average per month in kWh/m² at 35° tilt, south-facing, including the terrain horizon of Ahlen. P90 = reached in 9 out of 10 years.
Optimal tilt angle in Ahlen
The annual optimum for Ahlen is 40° south; anything between 24° and 51° counts as equivalent (below 2% difference). For winter operation (off-grid) 65° is optimal, for summer use 20°. Flat-laid modules lose 15.3 % versus the optimum. Adjusting twice a year would add 3.0 % here, monthly adjustment 3.5 % — only relevant for adjustable mounts.
Is a balcony solar kit worth it in Ahlen?
A vertical south-facing railing in Ahlen harvests 941 kWh/m² per year — 72 % of what an optimally tilted 35° panel yields at the same spot. December softens the penalty: with the low winter sun, the vertical plane reaches 111 % of the 35° December value, computed from the same hourly data with its own plane transposition. Open the balcony solar calculator with these coordinates →