Location data · North Rhine-Westphalia

Sun hours in Troisdorf

How sunny is Troisdorf? Over a year the sun delivers 1,290 kilowatt-hours onto every square metre here — in June roughly 5 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 3.53 peak sun hours per day in Troisdorf. In 9 out of 10 years at least 1,211 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.

Annual average (PSH)
3.53 kWh/m²/d
P90 annual total
1,211 kWh/m²
Optimal tilt
35°
Terrain horizon max.
5.7°

Sun hours per month

MonthJanFebMarAprMayJunJulAugSepOctNovDec
PSH/day (35° south)1.272.263.524.895.105.465.314.864.242.771.601.08
P900.971.572.704.134.364.614.604.233.662.311.240.75

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

Optimal tilt angle in Troisdorf

The annual optimum for Troisdorf is 35° south; anything between 23° and 50° counts as equivalent (below 2% difference). For winter operation (off-grid) 65° is optimal, for summer use 20°. Flat-laid modules lose 13.7 % versus the optimum. Adjusting twice a year would add 2.9 % here, monthly adjustment 3.7 % — only relevant for adjustable mounts.

Is a balcony solar kit worth it in Troisdorf?

A vertical south-facing railing in Troisdorf harvests 917 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 117 % 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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