Location data · Vaud
Sun hours in Lausanne
How sunny is Lausanne? Over a year the sun delivers 1,566 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 4.29 peak sun hours per day in Lausanne. In 9 out of 10 years at least 1,466 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.
- Annual average (PSH)
- 4.29 kWh/m²/d
- P90 annual total
- 1,466 kWh/m²
- Optimal tilt
- 40°
- Terrain horizon max.
- 20.6°
Sun hours per month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PSH/day (35° south) | 2.35 | 3.53 | 4.42 | 5.33 | 5.22 | 5.91 | 6.05 | 5.60 | 4.97 | 3.63 | 2.41 | 2.03 |
| P90 | 1.80 | 2.99 | 3.59 | 4.32 | 4.59 | 5.21 | 5.34 | 4.95 | 4.49 | 2.95 | 1.81 | 1.52 |
Daily average per month in kWh/m² at 35° tilt, south-facing, including the terrain horizon of Lausanne. P90 = reached in 9 out of 10 years.
Optimal tilt angle in Lausanne
The annual optimum for Lausanne is 40° south; anything between 26° and 51° counts as equivalent (below 2% difference). For winter operation (off-grid) 65° is optimal, for summer use 20°. Flat-laid modules lose 17.3 % versus the optimum. Adjusting twice a year would add 3.3 % here, monthly adjustment 4.3 % — only relevant for adjustable mounts.
Is a balcony solar kit worth it in Lausanne?
A vertical south-facing railing in Lausanne harvests 1,112 kWh/m² per year — 71 % 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 111 % 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
- Renens4.24 kWh/m²/d4 km
- Montreux4.54 kWh/m²/d23 km
- Yverdon-les-Bains4.39 kWh/m²/d29 km