Location data · Bern
Sun hours in Thun
How sunny is Thun? Over a year the sun delivers 1,496 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 4.10 peak sun hours per day in Thun. In 9 out of 10 years at least 1,419 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.
- Annual average (PSH)
- 4.10 kWh/m²/d
- P90 annual total
- 1,419 kWh/m²
- Optimal tilt
- 40°
- Terrain horizon max.
- 17.2°
Sun hours per month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PSH/day (35° south) | 2.34 | 3.48 | 4.43 | 5.07 | 4.82 | 5.42 | 5.53 | 5.19 | 4.78 | 3.69 | 2.38 | 2.03 |
| P90 | 1.74 | 3.03 | 3.56 | 4.08 | 4.01 | 4.64 | 4.83 | 4.28 | 4.34 | 3.11 | 1.90 | 1.56 |
Daily average per month in kWh/m² at 35° tilt, south-facing, including the terrain horizon of Thun. P90 = reached in 9 out of 10 years.
Optimal tilt angle in Thun
The annual optimum for Thun is 40° south; anything between 27° and 52° counts as equivalent (below 2% difference). For winter operation (off-grid) 65° is optimal, for summer use 20°. Flat-laid modules lose 17.9 % versus the optimum. Adjusting twice a year would add 3.5 % here, monthly adjustment 4.4 % — only relevant for adjustable mounts.
Is a balcony solar kit worth it in Thun?
A vertical south-facing railing in Thun harvests 1,083 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 109 % of the 35° December value, computed from the same hourly data with its own plane transposition. Open the balcony solar calculator with these coordinates →