Location data · Vorarlberg
Sun hours in Dornbirn
How sunny is Dornbirn? Over a year the sun delivers 1,430 kilowatt-hours onto every square metre here — in June roughly 3 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 3.92 peak sun hours per day in Dornbirn. In 9 out of 10 years at least 1,343 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.
- Annual average (PSH)
- 3.92 kWh/m²/d
- P90 annual total
- 1,343 kWh/m²
- Optimal tilt
- 40°
- Terrain horizon max.
- 16.0°
Sun hours per month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PSH/day (35° south) | 2.14 | 3.26 | 4.03 | 4.90 | 4.77 | 5.37 | 5.45 | 5.06 | 4.50 | 3.52 | 2.17 | 1.84 |
| P90 | 1.55 | 2.69 | 3.08 | 4.06 | 3.87 | 4.56 | 4.74 | 4.16 | 3.78 | 2.92 | 1.58 | 1.23 |
Daily average per month in kWh/m² at 35° tilt, south-facing, including the terrain horizon of Dornbirn. P90 = reached in 9 out of 10 years.
Optimal tilt angle in Dornbirn
The annual optimum for Dornbirn is 40° south; anything between 26° and 52° counts as equivalent (below 2% difference). For winter operation (off-grid) 65° is optimal, for summer use 20°. Flat-laid modules lose 17.0 % versus the optimum. Adjusting twice a year would add 3.0 % here, monthly adjustment 3.8 % — only relevant for adjustable mounts.
Is a balcony solar kit worth it in Dornbirn?
A vertical south-facing railing in Dornbirn harvests 1,027 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 104 % 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
- Feldkirch4.11 kWh/m²/d23 km
- St. Gallen3.91 kWh/m²/d28 km
- Wangen im Allgäu4.13 kWh/m²/d31 km