How Many Batteries for a 5kVA Inverter? Lithium vs Tubular, with Hours of Backup
A 5kVA inverter needs 2 × 5.12kWh lithium modules for a typical family home, or at least 4 tubular batteries. For a 1kW load through 8 hours that is 2 lithium modules (about ₦2.61M) or 8 tubulars (about ₦1.6M).
The table: load × hours → batteries → cost
Pick the row closest to what you want running when the grid is off and for how long. The kWh column is the energy that takes; the battery counts are what holds that much usable energy on a 5kVA (48V) system.
| Load | Hours | Energy | Lithium modules | Lithium cost | Tubulars | Tubular cost |
|---|---|---|---|---|---|---|
| 1kW | 4h | 4kWh | 1 × 5.12kWh | ₦1.31M | 4 × 200Ah | ₦800k |
| 1kW | 8h | 8kWh | 2 × 5.12kWh | ₦2.61M | 8 × 200Ah | ₦1.6M |
| 1kW | 12h | 12kWh | 3 × 5.12kWh | ₦3.92M | 12 × 200Ah | ₦2.4M |
| 2kW | 4h | 8kWh | 2 × 5.12kWh | ₦2.61M | 8 × 200Ah | ₦1.6M |
| 2kW | 8h | 16kWh | 4 × 5.12kWh | ₦5.22M | 16 × 200Ah | ₦3.2M |
| 2kW | 12h | 24kWh | 6 × 5.12kWh | ₦7.83M | 20 × 200Ah | ₦4M |
| 3kW | 4h | 12kWh | 3 × 5.12kWh | ₦3.92M | 12 × 200Ah | ₦2.4M |
| 3kW | 8h | 24kWh | 6 × 5.12kWh | ₦7.83M | 20 × 200Ah | ₦4M |
| 3kW | 12h | 36kWh | 9 × 5.12kWh | ₦11.8M | 32 × 200Ah | ₦6.4M |
Lithium counted at 80% usable, tubular at 50%, tubulars in sets of 4 for 48V. Costs at typical mid-class prices. 1kW is lights, fans, TV, a fridge and Wi-Fi; 2kW adds a small AC; 3kW is a 1.5HP AC with the rest of the house.
What each battery costs
| Item | Low | Typical | High |
|---|---|---|---|
| Lithium module, 5.12kWh 48V (mid class) | ₦1,024,000 | ₦1,305,600 | ₦1,689,600 |
| Tubular 200Ah 12V | ₦160,000 | ₦200,000 | ₦300,000 |
| 4 tubulars, one 48V set | ₦640,000 | ₦800,000 | ₦1,200,000 |
Market prices, checked October 2026; our quotes add a 5% sourcing fee.
Why the 12-hour rows look so large
Because running a house all night on batteries alone is expensive, and anyone who tells you otherwise has not costed it. Most homes do not need it: with some grid supply, the battery only has to cover the hours the grid is off after dark, and the panels refill it the next day. That is why our engine’s typical 5kVA build carries 2 modules, not 9. If your evenings are long and your grid is poor, the calculator lets you set grid supply to “poor” or “none” and watch the battery grow.
And for a 3.5kVA inverter?
A 3.5kVA inverter usually runs a 24V battery, so tubulars go in pairs and lithium is a 24V module of the same 5.12kWh. For the representative load on our what can a 3.5kVA inverter run page, the engine fits 2 lithium modules (10.24kWh). Same rule as above: the hours come from the battery, not the inverter.
And for a 2.5kVA inverter?
A 2.5kVA inverter usually runs a 24V battery, so tubulars go in pairs and lithium is a 24V module of the same 5.12kWh. For the representative load on our what can a 2.5kVA inverter run page, the engine fits 2 lithium modules (10.24kWh). Same rule as above: the hours come from the battery, not the inverter.
Questions people ask
How many lithium batteries for a 5kVA inverter?
Usually 2: our engine puts 2 × 5.12kWh 48V modules on a typical 5kVA family home with some grid. One module is the minimum that works; each extra module adds about 4.1kWh of usable backup.
How many tubular batteries for a 5kVA inverter?
At least 4, because a 5kVA runs a 48V bank and each tubular is 12V. More backup means another set of 4, not one more battery. 4 × 200Ah gives about 4.8kWh usable.
How long will a 5kVA inverter run on batteries?
Usable battery kWh divided by your load in kW. 10.24kWh of lithium gives about 8.19kWh usable, so roughly 8 hours at 1kW, or half that at 2kW. The inverter size does not change the hours; the battery does.
Can I mix lithium and tubular batteries?
No. They charge at different voltages and the inverter can only be set for one battery type. Pick one and build the bank from matching units bought together.
Related pages
Not sure how many hours you need?
Tell us what has to stay on when NEPA goes and for how long. We will work out the battery with you.