Peak Sun Hours in Jacksonville, Florida, United States
- Solar zone
- Zone 3 (good)
- Best month
- May (6.5)
- Worst month
- December (2.8)
- Climate
- Temperate · 20.4°C
Monthly solar breakdown
| Month | GHI | Clear-sky | DNI | DHI | Temp °C | Humid % |
|---|---|---|---|---|---|---|
| Jan | 3.09 | 4.03 | 3.93 | 1.25 | 11.2 | 80 |
| Feb | 3.74 | 4.99 | 4.21 | 1.44 | 13.4 | 80 |
| Mar | 4.96 | 6.21 | 5.12 | 1.73 | 16.6 | 76 |
| Apr | 6.05 | 7.27 | 5.90 | 1.98 | 20.6 | 71 |
| May | 6.53 | 7.76 | 5.88 | 2.22 | 24.6 | 68 |
| Jun | 6.12 | 7.77 | 4.66 | 2.48 | 26.9 | 76 |
| Jul | 6.13 | 7.58 | 4.74 | 2.46 | 27.6 | 79 |
| Aug | 5.65 | 7.07 | 4.54 | 2.27 | 27.4 | 81 |
| Sep | 4.90 | 6.29 | 4.37 | 1.98 | 25.6 | 81 |
| Oct | 4.19 | 5.25 | 4.72 | 1.52 | 21.5 | 80 |
| Nov | 3.36 | 4.21 | 4.37 | 1.24 | 16.5 | 79 |
| Dec | 2.76 | 3.67 | 3.60 | 1.17 | 13.4 | 82 |
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 2.76 kWh/m²/day, 0.77 system efficiency.
About solar in Jacksonville
Jacksonville, United States has a temperate climate with meaningful seasonal variation in solar resource. Its annual peak sun hours average 4.79 kWh/m²/day, a good solar resource by global standards.
The strongest month in Jacksonville is May (spring) at 6.53 kWh/m²/day, and the weakest is December (winter) at 2.76 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.
Jacksonville'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 Jacksonville?
- Jacksonville averages 4.79 peak sun hours per day annually, ranging from 2.76 in December to 6.53 in May.
- How many solar panels do I need in Jacksonville?
- Panel count depends on your daily load. At Jacksonville's annual average of 4.79 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 Jacksonville?
- Sizing against Jacksonville's worst month (December, 2.76 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 Jacksonville's solar resource compare globally?
- Jacksonville sits in solar zone 3 out of 5 (where 5 is strongest) at 4.79 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 Jacksonville?
- Jacksonville's worst month (December) delivers 2.76 kWh/m²/day — about 42% of the summer peak of 6.53. Off-grid systems here typically oversize 1.5–2× or pair with a backup source.
- Do cloudy days significantly affect Jacksonville's solar?
- Partly. Diffuse light still produces 10–25% of clear-sky output. Jacksonville's 4.79 kWh/m²/day already reflects average cloudiness, so no further derating is needed for sizing.
- What panel tilt works best in Jacksonville?
- At Jacksonville's latitude (30°), a fixed tilt near 30° balances year-round yield. Winter-heavy loads favor latitude + 15°; summer-heavy, latitude − 15°.