Size.Solar
Solar yield in Lagos
Estimated annual solar yield is 1234 kWh per kWp per year. A 400W panel is estimated to produce 494 kWh/year, or 1.35 kWh/day, after modelled system conversion losses.
Provider-backed estimate
NLR PVWatts 8.5.0, using TMY dataset (2022 release) weather data. The model assumes south-facing panels at 7° tilt, 180° azimuth, and 14% system losses.
Retrieved . Compare tilt and direction.
The estimate is before site-specific roof angle, shade, weather, and equipment factors.
Current estimate
Annual savings
₦772,313
Use covered
95%
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Your system settings
Annual bill savings
₦772,313
Average monthly bill value of ₦64,359, based on monthly production and capped to the 600 kWh/month use you entered.
Electricity use covered
95%
Surplus in higher-production months: 541 kWh/year. Export credits or batteries may add value.
Annual output
7,405 kWh
Daily output
~20 kWh
System size
6.0 kW
Panels needed
15 panels*
Will this system fit your roof?
Keep these inputs while you outline usable roof space and refine the estimate. Compare installers when the roof plan is ready.
Monthly production breakdown (kWh)
Next accuracy check
Check this estimate against your roof
The figures below are an example starting point for Lagos: 15 panels at 400W, about 6.0 kW, and a 600 kWh/month electricity-use target. Review your current panel wattage, panel count, and electricity use in the calculator above before opening the roof planner or comparing installers.
- Example system
- ~6.0 kW
15 panels for a 600 kWh/month home before roof, inverter, and battery constraints.
- Output per panel
- 494 kWh
Estimated annual AC electricity from one 400W panel after modelled system losses.
- Bill value/year
- ₦772,313
Annual value at about NGN 112.50/kWh, capped to the electricity use you can actually offset.
- Weakest month
- Sep
33 kWh from one 400W panel; check this month before sizing essential loads.
Roof fit
Confirm usable roof planes, shading, inverter limits, and battery needs before accepting a final layout.
Bill fit
Adjust panel count and monthly use above so savings are capped to electricity you can offset.
Quote check
Ask suppliers to show winter output, assumed losses, and any export-credit value separately.
Production evidenceShow monthly output and model assumptionsOpen this when checking winter production, irradiance, losses, or the source assumptions behind the quote handoff.
Monthly model
Monthly output and winter risk
The calculator is useful when it shows the weak months, not just a flattering annual number. Use the table to check whether winter output still supports the loads you care about.
- Best month
- Mar
48 kWh from one 400W panel
- Lowest month
- Sep
33 kWh from one 400W panel
- Solar resource
- 4.6 kWh/m²/day
1677 kWh/m² annual irradiance
- Model checks
- 14.1%
Capacity factor, 73.6% performance ratio, 519 kWh DC before conversion
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 47 kWh | 45 kWh | 48 kWh | 44 kWh | 42 kWh | 34 kWh | 34 kWh | 36 kWh | 33 kWh | 40 kWh | 42 kWh | 48 kWh |
Model basis
The model uses south-facing panels at 7° tilt, true south orientation, and 14% system loss. Typical 600 kWh/month electricity costs are ₦33,750 - ₦101,250 (typically ₦67,500) using 2025 cost data.
Solar production data provided by NLR PVWatts 8.5.0. Weather source: NSRDB PSM V4 Meteosat Prime Meridian tmy-2022 1.0.0; nearest source point 1.6 km from the city coordinates.