Location data · Aargau
Sun hours in Aarau
How sunny is Aarau? Over a year the sun delivers 1,439 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 3.94 peak sun hours per day in Aarau. In 9 out of 10 years at least 1,349 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.
- Annual average (PSH)
- 3.94 kWh/m²/d
- P90 annual total
- 1,349 kWh/m²
- Optimal tilt
- 35°
- Terrain horizon max.
- 8.4°
Sun hours per month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PSH/day (35° south) | 1.67 | 2.84 | 4.08 | 5.12 | 5.21 | 5.81 | 5.85 | 5.38 | 4.72 | 3.22 | 1.91 | 1.46 |
| P90 | 1.30 | 2.02 | 3.05 | 3.95 | 4.53 | 5.10 | 5.13 | 4.63 | 4.17 | 2.63 | 1.57 | 1.15 |
Daily average per month in kWh/m² at 35° tilt, south-facing, including the terrain horizon of Aarau. P90 = reached in 9 out of 10 years.
Optimal tilt angle in Aarau
The annual optimum for Aarau is 35° south; anything between 23° and 49° counts as equivalent (below 2% difference). For winter operation (off-grid) 60° is optimal, for summer use 20°. Flat-laid modules lose 14.6 % versus the optimum. Adjusting twice a year would add 2.4 % here, monthly adjustment 3.2 % — only relevant for adjustable mounts.
Is a balcony solar kit worth it in Aarau?
A vertical south-facing railing in Aarau harvests 998 kWh/m² per year — 69 % 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 103 % 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
- Waldshut-Tiengen4.00 kWh/m²/d29 km
- Lörrach3.84 kWh/m²/d38 km
- Zürich4.03 kWh/m²/d38 km