Location data · North Rhine-Westphalia
Sun hours in Alsdorf
How sunny is Alsdorf? Over a year the sun delivers 1,358 kilowatt-hours onto every square metre here — in June roughly 4 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 3.72 peak sun hours per day in Alsdorf. In 9 out of 10 years at least 1,289 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.
- Annual average (PSH)
- 3.72 kWh/m²/d
- P90 annual total
- 1,289 kWh/m²
- Optimal tilt
- 40°
- Terrain horizon max.
- 1.5°
Sun hours per month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PSH/day (35° south) | 1.48 | 2.40 | 3.69 | 5.09 | 5.39 | 5.61 | 5.44 | 4.95 | 4.41 | 3.00 | 1.87 | 1.25 |
| P90 | 1.04 | 1.71 | 3.00 | 4.41 | 4.80 | 4.76 | 4.96 | 4.36 | 3.90 | 2.59 | 1.48 | 0.90 |
Daily average per month in kWh/m² at 35° tilt, south-facing, including the terrain horizon of Alsdorf. P90 = reached in 9 out of 10 years.
Optimal tilt angle in Alsdorf
The annual optimum for Alsdorf is 40° south; anything between 27° and 53° counts as equivalent (below 2% difference). For winter operation (off-grid) 70° is optimal, for summer use 20°. Flat-laid modules lose 17.2 % versus the optimum. Adjusting twice a year would add 3.5 % here, monthly adjustment 4.3 % — only relevant for adjustable mounts.
Is a balcony solar kit worth it in Alsdorf?
A vertical south-facing railing in Alsdorf harvests 1,000 kWh/m² per year — 74 % 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 121 % of the 35° December value, computed from the same hourly data with its own plane transposition. Open the balcony solar calculator with these coordinates →
Neighbouring places compared
- Stolberg, Rheinland3.47 kWh/m²/d12 km
- Aachen3.51 kWh/m²/d12 km
- Heinsberg3.69 kWh/m²/d21 km