Location data · Neuchâtel

Sun hours in La Chaux-de-Fonds

How sunny is La Chaux-de-Fonds? Over a year the sun delivers 1,543 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 4.23 peak sun hours per day in La Chaux-de-Fonds. In 9 out of 10 years at least 1,459 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.

Annual average (PSH)
4.23 kWh/m²/d
P90 annual total
1,459 kWh/m²
Optimal tilt
35°
Terrain horizon max.
8.8°

Sun hours per month

MonthJanFebMarAprMayJunJulAugSepOctNovDec
PSH/day (35° south)2.203.314.475.355.356.066.105.645.013.482.091.66
P901.772.563.414.244.495.355.365.054.372.911.601.34

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

Optimal tilt angle in La Chaux-de-Fonds

The annual optimum for La Chaux-de-Fonds is 35° south; anything between 24° and 50° counts as equivalent (below 2% difference). For winter operation (off-grid) 65° is optimal, for summer use 20°. Flat-laid modules lose 15.0 % versus the optimum. Adjusting twice a year would add 3.2 % here, monthly adjustment 4.1 % — only relevant for adjustable mounts.

Is a balcony solar kit worth it in La Chaux-de-Fonds?

A vertical south-facing railing in La Chaux-de-Fonds harvests 1,079 kWh/m² per year — 70 % 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 110 % 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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