9 places · sun position · panel angle
Solar data for Slovenia
Across the 9 places in Slovenia the best fixed tilt for solar panels runs from 36° in Koper to 38° in Maribor, and flat ground gets 3.5 to 3.8 peak sun hours a day. Every number is computed for each place.
Solar power in Slovenia at a glance
Averages over 9 places with climate data, for a fixed array facing south.
- 3.47–3.53
- 3.53–3.59
- 3.59–3.65
- 3.65–3.71
- 3.71–3.77
Peak sun hours a day on flat ground. Each dot is one place.
The sunniest place in Slovenia is Koper (Urban Municipality of Koper) with 3.77 peak sun hours a day on flat ground; the least sunny is Maribor with 3.47. A 1 kWp array at its best angle makes from 1,252 kWh a year in Maribor to 1,336 kWh in Koper — 1,273 kWh on average.
The best year-round tilt runs from 36° in Koper to 38° in Maribor. Off-grid systems are sized for the darkest month and do better steeper, at 71° on average: at 70° that month brings 1.97 kWh per kWp a day in Ptuj and 2.19 kWh in Kranj.
Size an off-grid system or open any place below for its sun path, monthly table and tilt curve.
Sunniest places in Slovenia
Ranked by peak sun hours on flat ground: the yearly average of a day's sunshine energy (NASA POWER climatology). Output: 1 kWp at its best year-round angle.
| Rank | Place | Region | Sun hours/day | kWh per kWp a year | Best tilt |
|---|---|---|---|---|---|
| 1 | Koper | Urban Municipality of Koper | 3.77 | 1,336 | 36° |
| 2 | Novo Mesto | Urban Municipality of Novo Mesto | 3.56 | 1,273 | 37° |
| 3 | Ljubljana | Ljubljana | 3.53 | 1,274 | 37° |
| 4 | Kranj | Urban Municipality of Kranj | 3.51 | 1,278 | 38° |
| 4 | Trbovlje | Municipality of Trbovlje | 3.51 | 1,266 | 37° |
| 4 | Ptuj | Urban Municipality of Ptuj | 3.51 | 1,259 | 37° |
| 7 | Celje | Urban Municipality of Celje | 3.50 | 1,262 | 37° |
| 8 | Velenje | Urban Municipality of Velenje | 3.49 | 1,260 | 38° |
| 9 | Maribor | Urban Municipality of Maribor | 3.47 | 1,252 | 38° |
Solar by region in Slovenia
Averages of the places in each region, sunniest first. Darkest month: what 1 kWp of off-grid panels at 70° makes a day in the worst month of the year.
| Region | Places | Sun hours/day | kWh per kWp a year | Best tilt | Darkest month at 70° | Sunniest place |
|---|---|---|---|---|---|---|
| Urban Municipality of Koper | 1 | 3.77 | 1,336 | 36° | 2.13 kWh | Koper |
| Urban Municipality of Novo Mesto | 1 | 3.56 | 1,273 | 37° | 2.10 kWh | Novo Mesto |
| Ljubljana | 1 | 3.53 | 1,274 | 37° | 2.11 kWh | Ljubljana |
| Municipality of Trbovlje | 1 | 3.51 | 1,266 | 37° | 2.11 kWh | Trbovlje |
| Urban Municipality of Kranj | 1 | 3.51 | 1,278 | 38° | 2.19 kWh | Kranj |
| Urban Municipality of Ptuj | 1 | 3.51 | 1,259 | 37° | 1.97 kWh | Ptuj |
| Urban Municipality of Celje | 1 | 3.50 | 1,262 | 37° | 2.11 kWh | Celje |
| Urban Municipality of Velenje | 1 | 3.49 | 1,260 | 38° | 2.12 kWh | Velenje |
| Urban Municipality of Maribor | 1 | 3.47 | 1,252 | 38° | 2.06 kWh | Maribor |
Largest places in Slovenia at a glance
Daylight and clock time in Slovenia
In Maribor (46.6° N), the northernmost place, the longest day of the year lasts 15 h 50 min and the shortest 8 h 34 min; in Koper (45.5° N), the southernmost, 15 h 42 min and 8 h 42 min. The clocks change twice a year: forward on Sun 29 Mar, back on Sun 25 Oct (Europe/Ljubljana).
| Time zone | Places | UTC offset | Clocks change in 2026 |
|---|---|---|---|
| Europe/Ljubljana | 9 | UTC+1, in summer UTC+2 | Forward on Sun 29 Mar, back on Sun 25 Oct |