Location data · North Rhine-Westphalia
Sun hours in Sundern
How sunny is Sundern? Over a year the sun delivers 1,209 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 3.31 peak sun hours per day in Sundern. In 9 out of 10 years at least 1,130 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.
- Annual average (PSH)
- 3.31 kWh/m²/d
- P90 annual total
- 1,130 kWh/m²
- Optimal tilt
- 40°
- Terrain horizon max.
- 2.3°
Sun hours per month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PSH/day (35° south) | 1.09 | 2.07 | 3.41 | 4.62 | 4.80 | 5.20 | 5.00 | 4.60 | 3.90 | 2.56 | 1.45 | 0.99 |
| P90 | 0.73 | 1.49 | 2.59 | 3.73 | 3.99 | 4.43 | 4.36 | 3.93 | 3.31 | 1.96 | 1.00 | 0.73 |
Daily average per month in kWh/m² at 35° tilt, south-facing, including the terrain horizon of Sundern. P90 = reached in 9 out of 10 years.
Optimal tilt angle in Sundern
The annual optimum for Sundern is 40° south; anything between 25° and 52° counts as equivalent (below 2% difference). For winter operation (off-grid) 65° is optimal, for summer use 20°. Flat-laid modules lose 15.4 % versus the optimum. Adjusting twice a year would add 3.1 % here, monthly adjustment 4.1 % — only relevant for adjustable mounts.
Is a balcony solar kit worth it in Sundern?
A vertical south-facing railing in Sundern harvests 877 kWh/m² per year — 73 % 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 116 % of the 35° December value, computed from the same hourly data with its own plane transposition. Open the balcony solar calculator with these coordinates →