Every price, saving and payback period on this site comes from a model we can show you. This page sets out how it works: what goes into a price, how we size a system, how we work out what it saves, and every assumption behind the numbers, with where each one comes from. If you are comparing quotes, or an AI assistant is summarising us, this is the page to check against.
What does an InfraSol price include?
Our package prices are installed prices: everything needed to switch the system on, with nothing added later. Each one is built from a costing sheet with the same lines every time:
- Panels, inverter(s) and lithium battery, at the price we pay our supplier.
- Mounting rails, clamps, solar cable and DC protection, per panel.
- AC and DC breakers, surge protection, battery breaker, AC cable and changeover, per inverter.
- Earthing, enclosures, trunking and consumables, per site.
- Installation and engineering, per site and per inverter.
- Transport to site.
- Remote monitoring, set up and handed over.
The price on the page is that total plus our margin, rounded. We publish it because the most common complaint about solar in Nigeria is a quote that grows after the deposit. Prices on the site are as of November 2026, and we update them when supplier prices move. Equipment we sell on its own is priced the same way, without installation: see the price list.
How do we decide what size system you need?
Three numbers size a system, and each answers a different question.
| Number | The question it answers | How we set it |
|---|---|---|
| Inverter (kVA) | What can run at the same time? | The largest load you run together, plus headroom for motors and compressors starting. |
| Panels (kWp) | How much energy is made each day? | Your daily use, at 3.45–5.35 peak sun hours a day. We check the harmattan and peak-rains months, not just the annual average. |
| Battery (kWh) | How long can you run without sun? | Your night-time load × the hours you want covered, using 90% of the battery's capacity. |
For homes, air conditioners decide the size more than anything else, so we start by counting how many need to run at night. The working, size by size, is in our sizing guide and how many panels and batteries each inverter needs.
How does the solar calculator work?
It simulates a full year, hour by hour: 8,760 hours of sun, grid and load. The sunshine follows the measured output of a 74kWp system we installed in Lagos, scaled to the Lagos annual average, and the grid follows measured supply on a Band A feeder in Lekki Phase 1, outages included. Each hour, the model meets the load from the cheapest source available to you, starting with solar, and runs the generator only when nothing cheaper is left. From your monthly NEPA and diesel spend it works back to the smallest system that takes the generator off the job, and shows what that system costs. You can try it with your own bills.
How do we work out what a system saves?
Savings are the solar energy you actually use, valued at what that energy costs you today. Panels in Lagos make about 1,397 kWh per kWp a year after system losses. We count 75% of that as used in a home and 90% in a business, because some solar is wasted when the battery is full and nothing is running. Payback is the installed price divided by the yearly saving.
What that energy is worth depends on where it would otherwise have come from. We use three customer types:
| Customer | Mains supply | Blended cost per kWh |
|---|---|---|
| Band A home, evening-heavy load | 14–18 hours a day | ₦366 |
| Band B/C small business | About 10 hours a day | ₦531 |
| Band C/D commercial site, daytime load | Minimal | ₦625 |
How do we work out the cost of generator power?
We derive it from fuel burn rather than assume it. A generator burns fuel in proportion to the load and, separately, in proportion to its own size whether or not anything is plugged in.
Generator fuel burn
- litres per hour ≈ 0.25 × kW drawn + 0.037 × rated kVA
- Typical Lagos set: 40–70% loaded, so about 3 kWh per litre
- Diesel at ₦1,920 a litre ÷ 2.99 kWh
≈ ₦640 per kWh in fuel; ₦60–₦120 more for servicing, overhaul and fuel losses
Every assumption, and where it comes from
| Assumption | Value | Source |
|---|---|---|
| Diesel price | ₦1,920 per litre | Lagos pump and bulk prices we pay on site; see the diesel tracker |
| Band A grid tariff | ₦210 per kWh | NERC Band A rate (₦209.50 since July 2024) |
| Exchange rate | ₦1,380 per $ | Working rate, in line with the official market |
| Solar yield, Lagos | 1,397 kWh per kWp a year | Measured on a 74kWp array we installed in Lagos, anchored to the Global Solar Atlas; the same figure our simulator uses |
| Peak sun hours | 3.45–5.35 a day | Monthly range; the low end is harmattan and peak rains |
| Dirty-panel loss | 30–50% | Measured on our monitored arrays left uncleaned for months |
| Battery round trip | 88% | LiFePO₄ behind a hybrid inverter, charge and discharge combined |
| Usable battery | 90% of capacity | LiFePO₄ rated depth of discharge |
| Solar used | 75% homes, 90% businesses | Share of output not wasted when the battery is full |
| Generator fuel | 0.25 L/h per kW + 0.037 L/h per kVA | Standard diesel genset curve, calibrated to fuel logs from sites we monitor |
Where we choose to be conservative
- We value Band A at the bottom of its range, so we never overstate what a grid-connected customer saves.
- Package paybacks give the battery no credit for charging from the grid, though it saves money that way too.
- We quote payback publicly as 1.5–3.5 years, the cautious end of what the model shows.
- Generator fuel stays under ₦700 per kWh in our figures. We only use ₦700+ once servicing, overhaul and fuel losses are added, and we say so.
- Where official data is wrong (NBS's April–May 2026 diesel prices, for example) we say so, explain our replacement figure and label it as an estimate.
How we finance a system
Lease-to-own takes 30–40% down and the balance over 3, 6 or 12 monthly payments, at a monthly rate on the reducing balance. You own the system at the end. The monthly payment for each package is on its page and on the financing page.
