What it yields where you are
How much solar produces in L'Aquila
In L'Aquila a well-oriented system produces 1,414 kWh a year for every kWp installed. A 6 kW system — a home-sized one — makes about 8,487 kWh a year. The figures below come from PVGIS, the European Commission's database.
1,414
kWh a year for every kWp
8,487
kWh a year from a 6 kW system
37°
the best tilt, facing south
01At a glance
A year of sun in L'Aquila.
A 6 kW system produces
8,487 kWh
About what 4.2 households use in a year.
The best month
July
945 kWh: 2.0 times the worst month.
Hours of sunshine a year
3,491 h
9.6 hours a day on average. In the leanest month it drops to 6.3.
How cloudy the sky is
55%
Average over the year. The cloudiest month is November, at 71%.
Warmest month's temperature
22.9 °C
In the coldest month the average is 3.3 °C.
How much it changes year to year
from −5% to +6%
Sunlight measured over the last twenty years, against the average.
02System sizes
How much a system produces in L'Aquila
The three sizes people actually put on a house, on the best plane.
3 kW
4,243
Produces each year · kWh
450 W modules: 7
6 kW
8,487
Produces each year · kWh
450 W modules: 13
10 kW
14,145
Produces each year · kWh
450 W modules: 22
03Month by month
Month by month in L'Aquila
A yearly total doesn't say when the energy arrives, and that's the part that decides whether you need storage.
A 6 kW system yields most in July, with 945 kWh, and least in November, with 462: 2.0 times as much. That's why the summer bill goes to zero and the winter one doesn't.
| Month | Output of 6 kW | Sunshine | Cloud | Temperature | Days above 30°C |
|---|---|---|---|---|---|
| January | 503 kWh | 196 h | 66% | 3.3 °C | — |
| February | 576 kWh | 218 h | 61% | 5.1 °C | — |
| March | 733 kWh | 271 h | 64% | 6.6 °C | — |
| April | 761 kWh | 311 h | 59% | 10.2 °C | — |
| May | 811 kWh | 348 h | 61% | 14.2 °C | — |
| June | 862 kWh | 388 h | 43% | 19.4 °C | 3 |
| July | 945 kWh | 420 h | 26% | 22.9 °C | 12 |
| August | 913 kWh | 390 h | 32% | 22.4 °C | 11 |
| September | 776 kWh | 310 h | 53% | 17.3 °C | 1 |
| October | 676 kWh | 256 h | 62% | 13.4 °C | — |
| November | 462 kWh | 193 h | 71% | 8.8 °C | — |
| December | 465 kWh | 190 h | 62% | 5.2 °C | — |
Heat costs yield: above 25 °C of cell temperature a panel loses about 0.4% per degree, and in summer the cell runs some twenty degrees above the air. Here there are 26 days above 30 °C a year, nearly all between June and August. That loss is already inside the figures above — don't subtract it twice — but it is why July, which gets the most sun of any month, never yields as much as the extra sun would suggest.
Output: our own calculation on PVGIS irradiation, calibrated against PVGIS city by city and month by month. Sunshine, cloud, temperature and hot days: ten-year averages 2015-2024 from the ERA5 reanalysis, via Open-Meteo. Two different sources, in separate columns on purpose.
04Orientation
And if the roof doesn't face south
In L'Aquila the two sides are not equivalent, and it's worth knowing beforehand: compared with a south-facing roof you lose about 16% facing east and 22% facing west. The sun's geometry is symmetrical and the sky is not: morning air is clearer than afternoon air, or the other way round, and over a full year the difference shows. On a roof facing the wrong way it costs as much as a smaller system.
South-facing, 30°
1,400 kWh/kWp
The benchmark
East-facing, 30°
1,179 kWh/kWp
−16% compared with south
West-facing, 30°
1,092 kWh/kWp
−22% compared with south
05The years
And if next year is cloudy?
Fair question: the sun isn't the same every year. Here is how much it actually varied, from 2005 to 2024.
Over twenty years the poorest was 2010: 5% below average. The most generous was 2022: 6% above. Every other year sits in between. That's why a solar estimate uses the average of many years and not the last one — a bad year doesn't change the maths of a system that lasts twenty-five.
Yearly irradiation from 2005 to 2024 according to the ERA5 reanalysis, via Open-Meteo, against its own average. This is a different database from the one behind the output figures above, which comes from PVGIS and stops at 2023 — which is why the two periods don't match.
06For designers
The technical figures
The ones a designer needs. If you don't know them, you don't need them: everything is above.
Yield per installed kW
1,414 kWh/kWp
How many kWh each kW of panels gives in a year, on the best possible roof.
Best tilt
37°
The angle worth using here, facing south.
Sunlight reaching the ground
1,528 kWh/m²
Solar energy landing on one flat square metre in a year.
Other cities
Your roof isn't an average.
These figures are for an ideal roof in L'Aquila. The estimate on your address accounts for your roof, the shade and your consumption: two minutes, without leaving your contact details.