Peak Sun Hours in Atlanta, Georgia, United States
- Solar zone
- Zone 3 (good)
- Best month
- June (6.2)
- Worst month
- December (2.4)
- Climate
- Temperate · 16.6°C
Monthly solar breakdown
| Month | GHI | Clear-sky | DNI | DHI | Temp °C | Humid % |
|---|---|---|---|---|---|---|
| Jan | 2.75 | 3.76 | 4.08 | 1.02 | 5.4 | 82 |
| Feb | 3.28 | 4.77 | 3.88 | 1.31 | 7.5 | 82 |
| Mar | 4.38 | 6.04 | 4.31 | 1.73 | 11.7 | 81 |
| Apr | 5.59 | 7.20 | 5.08 | 2.09 | 16.2 | 78 |
| May | 6.16 | 7.74 | 4.93 | 2.47 | 21.0 | 75 |
| Jun | 6.19 | 7.81 | 4.35 | 2.72 | 25.2 | 73 |
| Jul | 6.02 | 7.51 | 4.11 | 2.72 | 26.9 | 71 |
| Aug | 5.49 | 6.91 | 3.90 | 2.50 | 26.6 | 70 |
| Sep | 4.82 | 6.12 | 4.47 | 1.90 | 23.4 | 70 |
| Oct | 3.97 | 5.07 | 4.94 | 1.30 | 17.4 | 72 |
| Nov | 3.09 | 3.97 | 4.65 | 1.01 | 11.0 | 74 |
| Dec | 2.37 | 3.38 | 3.61 | 0.92 | 7.2 | 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 2.37 kWh/m²/day, 0.77 system efficiency.
About solar in Atlanta
Atlanta, United States has a temperate climate with meaningful seasonal variation in solar resource. Its annual peak sun hours average 4.51 kWh/m²/day, a good solar resource by global standards.
The strongest month in Atlanta is June (summer) at 6.19 kWh/m²/day, and the weakest is December (winter) at 2.37 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.
Atlanta'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 Atlanta?
- Atlanta averages 4.51 peak sun hours per day annually, ranging from 2.37 in December to 6.19 in June.
- How many solar panels do I need in Atlanta?
- Panel count depends on your daily load. At Atlanta's annual average of 4.51 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 Atlanta?
- Sizing against Atlanta's worst month (December, 2.37 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 Atlanta's solar resource compare globally?
- Atlanta sits in solar zone 3 out of 5 (where 5 is strongest) at 4.51 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 Atlanta?
- Atlanta's worst month (December) delivers 2.37 kWh/m²/day — about 38% of the summer peak of 6.19. Off-grid systems here typically oversize 1.5–2× or pair with a backup source.
- Do cloudy days significantly affect Atlanta's solar?
- Partly. Diffuse light still produces 10–25% of clear-sky output. Atlanta's 4.51 kWh/m²/day already reflects average cloudiness, so no further derating is needed for sizing.
- What panel tilt works best in Atlanta?
- At Atlanta's latitude (34°), a fixed tilt near 34° balances year-round yield. Winter-heavy loads favor latitude + 15°; summer-heavy, latitude − 15°.