Peak Sun Hours in Cagliari, Sardinia, Italy
- Solar zone
- Zone 3 (good)
- Best month
- July (7.5)
- Worst month
- December (1.9)
- Climate
- Temperate · 18.2°C
Monthly solar breakdown
| Month | GHI | Clear-sky | DNI | DHI | Temp °C | Humid % |
|---|---|---|---|---|---|---|
| Jan | 2.08 | 2.91 | 3.11 | 0.95 | 12.3 | 78 |
| Feb | 2.96 | 4.02 | 3.68 | 1.32 | 11.8 | 77 |
| Mar | 4.12 | 5.46 | 4.12 | 1.82 | 13.1 | 79 |
| Apr | 5.30 | 6.82 | 4.70 | 2.23 | 15.1 | 80 |
| May | 6.42 | 7.80 | 5.67 | 2.49 | 18.0 | 78 |
| Jun | 7.43 | 8.24 | 7.26 | 2.32 | 22.1 | 74 |
| Jul | 7.52 | 7.98 | 7.78 | 2.08 | 25.3 | 71 |
| Aug | 6.59 | 7.09 | 6.97 | 1.93 | 25.9 | 70 |
| Sep | 4.89 | 5.78 | 5.12 | 1.83 | 23.4 | 72 |
| Oct | 3.54 | 4.32 | 4.25 | 1.44 | 20.6 | 77 |
| Nov | 2.26 | 3.08 | 3.03 | 1.07 | 16.8 | 78 |
| Dec | 1.86 | 2.55 | 3.02 | 0.84 | 13.7 | 77 |
GHI, Clear-sky, DNI, DHI in kWh/m²/day. Data: NASA POWER climatology (long-term monthly averages).
Off-grid calculator
Add appliances
- Add an appliance to size a system.
Sizing
- Daily load
- 0.00 kWh
- Panel wattage
- 0 W
- Panel count (400W modules)
- 0
- Battery bank
- 0.0 kWh
Sizing against worst-month PSH of 1.86 kWh/m²/day, 0.77 system efficiency.
About solar in Cagliari
Cagliari, Italy has a temperate climate with meaningful seasonal variation in solar resource. Its annual peak sun hours average 4.58 kWh/m²/day, a good solar resource by global standards.
The strongest month in Cagliari is July (summer) at 7.52 kWh/m²/day, and the weakest is December (winter) at 1.86 kWh/m²/day. When sizing a year-round off-grid system, it's standard practice to design against the December value rather than the annual average — otherwise the battery bank runs low during the darkest weeks.
Cagliari's solar conditions are well within the range where off-grid PV is a straightforward engineering exercise with standard-sized arrays and lithium batteries.
FAQ
- What are the peak sun hours in Cagliari?
- Cagliari averages 4.58 peak sun hours per day annually, ranging from 1.86 in December to 7.52 in July.
- How many solar panels do I need in Cagliari?
- Panel count depends on your daily load. At Cagliari's annual average of 4.58 kWh/m²/day, a 5 kWh/day load needs roughly 4 × 400 W panels. Use the calculator above for your actual load.
- What size battery do I need in Cagliari?
- Sizing against Cagliari's worst month (December, 1.86 kWh/m²/day) with 2 days of autonomy at 80% depth of discharge, a 5 kWh/day load needs about a 12.5 kWh battery bank.
- How does Cagliari's solar resource compare globally?
- Cagliari sits in solar zone 3 out of 5 (where 5 is strongest) at 4.58 kWh/m²/day — good by global standards. For reference, top-tier desert sites average ~6.5 and high-latitude cities around 2.5 kWh/m²/day.
- How much does winter reduce solar output in Cagliari?
- Cagliari's worst month (December) delivers 1.86 kWh/m²/day — about 25% of the summer peak of 7.52. Off-grid systems here typically oversize 1.5–2× or pair with a backup source.
- Do cloudy days significantly affect Cagliari's solar?
- Partly. Diffuse light still produces 10–25% of clear-sky output. Cagliari's 4.58 kWh/m²/day already reflects average cloudiness, so no further derating is needed for sizing.
- What panel tilt works best in Cagliari?
- At Cagliari's latitude (39°), a fixed tilt near 39° balances year-round yield. Winter-heavy loads favor latitude + 15°; summer-heavy, latitude − 15°.