Location data · Baden-Württemberg
Sun hours in Heilbronn
How sunny is Heilbronn? Over a year the sun delivers 1,417 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 3.88 peak sun hours per day in Heilbronn. In 9 out of 10 years at least 1,321 kWh/m² are reached. All values are computed from this location’s satellite hourly data, not estimated.
- Annual average (PSH)
- 3.88 kWh/m²/d
- P90 annual total
- 1,321 kWh/m²
- Optimal tilt
- 40°
- Terrain horizon max.
- 2.3°
Sun hours per month
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PSH/day (35° south) | 1.50 | 2.59 | 3.85 | 5.22 | 5.38 | 5.91 | 5.82 | 5.31 | 4.69 | 3.08 | 1.86 | 1.34 |
| P90 | 1.13 | 1.86 | 2.95 | 4.31 | 4.57 | 5.10 | 5.15 | 4.63 | 4.14 | 2.50 | 1.35 | 0.85 |
Daily average per month in kWh/m² at 35° tilt, south-facing, including the terrain horizon of Heilbronn. P90 = reached in 9 out of 10 years.
Optimal tilt angle in Heilbronn
The annual optimum for Heilbronn is 40° south; anything between 24° and 51° counts as equivalent (below 2% difference). For winter operation (off-grid) 65° is optimal, for summer use 20°. Flat-laid modules lose 15.5 % versus the optimum. Adjusting twice a year would add 3.0 % here, monthly adjustment 3.7 % — only relevant for adjustable mounts.
Is a balcony solar kit worth it in Heilbronn?
A vertical south-facing railing in Heilbronn harvests 1,008 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 107 % 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
- Öhringen3.85 kWh/m²/d22 km
- Bietigheim-Bissingen3.86 kWh/m²/d23 km
- Backnang3.71 kWh/m²/d27 km