Peak Sun Hours in Onitsha, Anambra, Nigeria
- Solar zone
- Zone 3 (good)
- Best month
- December (5.0)
- Worst month
- August (3.9)
- Climate
- Equatorial · 25.6°C
Monthly solar breakdown
| Month | GHI | Clear-sky | DNI | DHI | Temp °C | Humid % |
|---|---|---|---|---|---|---|
| Jan | 4.96 | 5.41 | 2.69 | 2.68 | 24.4 | 72 |
| Feb | 4.70 | 5.52 | 1.74 | 2.79 | 26.2 | 79 |
| Mar | 4.81 | 6.03 | 1.67 | 2.79 | 26.8 | 85 |
| Apr | 4.87 | 6.49 | 1.78 | 2.76 | 26.8 | 87 |
| May | 4.77 | 6.54 | 2.05 | 2.59 | 26.4 | 89 |
| Jun | 4.34 | 6.30 | 1.62 | 2.45 | 25.5 | 90 |
| Jul | 3.91 | 6.38 | 1.26 | 2.29 | 24.9 | 90 |
| Aug | 3.85 | 6.59 | 1.10 | 2.32 | 24.8 | 89 |
| Sep | 4.12 | 6.72 | 1.33 | 2.39 | 25.0 | 90 |
| Oct | 4.56 | 6.50 | 1.98 | 2.46 | 25.4 | 90 |
| Nov | 4.97 | 5.97 | 3.08 | 2.38 | 25.9 | 85 |
| Dec | 4.98 | 5.49 | 3.29 | 2.39 | 24.9 | 75 |
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 3.85 kWh/m²/day, 0.77 system efficiency.
About solar in Onitsha
Onitsha, Nigeria sits near the equator, where day length is stable year-round and the sun passes close to overhead. Its annual peak sun hours average 4.57 kWh/m²/day, a good solar resource by global standards.
The strongest month in Onitsha is December (winter) at 4.98 kWh/m²/day, and the weakest is August (summer) at 3.85 kWh/m²/day. When sizing a year-round off-grid system, it's standard practice to design against the August value rather than the annual average — otherwise the battery bank runs low during the darkest weeks.
Onitsha'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 Onitsha?
- Onitsha averages 4.57 peak sun hours per day annually, ranging from 3.85 in August to 4.98 in December.
- How many solar panels do I need in Onitsha?
- Panel count depends on your daily load. At Onitsha's annual average of 4.57 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 Onitsha?
- Sizing against Onitsha's worst month (August, 3.85 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 Onitsha's solar resource compare globally?
- Onitsha sits in solar zone 3 out of 5 (where 5 is strongest) at 4.57 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.
- Why doesn't solar output vary much by month in Onitsha?
- Near the equator, day length is nearly constant year-round and the sun stays close to overhead. In Onitsha, monthly PSH ranges just from 3.85 to 4.98 kWh/m²/day — variance is driven by wet-season cloud cover, not day length.
- What tilt angle works best for panels in Onitsha?
- At latitude 6°, panels in Onitsha work best at a low tilt (roughly 6°) or horizontal. Tracking mounts add little benefit this close to the equator.
- How does the wet season affect solar output in Onitsha?
- Equatorial wet seasons reduce output through cloud cover, not day length. Onitsha's worst month (August) still delivers 3.85 kWh/m²/day — design against this value for reliable year-round off-grid use.