Location data · Zurich

Sun hours in Winterthur

How sunny is Winterthur? Over a year the sun delivers 1,458 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 3.99 peak sun hours per day in Winterthur. In 9 out of 10 years at least 1,359 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.

Annual average (PSH)
3.99 kWh/m²/d
P90 annual total
1,359 kWh/m²
Optimal tilt
40°
Terrain horizon max.
6.9°

Sun hours per month

MonthJanFebMarAprMayJunJulAugSepOctNovDec
PSH/day (35° south)1.882.974.115.145.135.755.765.314.723.342.081.67
P901.362.153.054.074.374.945.044.414.042.811.641.22

Daily average per month in kWh/m² at 35° tilt, south-facing, including the terrain horizon of Winterthur. P90 = reached in 9 out of 10 years.

Optimal tilt angle in Winterthur

The annual optimum for Winterthur is 40° south; anything between 26° and 52° counts as equivalent (below 2% difference). For winter operation (off-grid) 70° is optimal, for summer use 20°. Flat-laid modules lose 17.2 % versus the optimum. Adjusting twice a year would add 3.4 % here, monthly adjustment 4.5 % — only relevant for adjustable mounts.

Is a balcony solar kit worth it in Winterthur?

A vertical south-facing railing in Winterthur harvests 1,047 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 118 % 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

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