Is solar cheaper than a generator in Nigeria? Per kWh, yes by a wide margin once the system is paid for: petrol generator ≈ ₦1.431–1.717/kWh including servicing at September 2026 prices; Band A grid ₦209.5/kWh; solar-plus-lithium ≈ ₦34–159/kWh over its life. A household spending ₦₦8k a day on a 2.5 kVA generator (six hours) spends about ₦3.53m a year, which is the price of a 3.5–5 kVA solar system every two to three years.
Cost per kWh, three sources
| Source | ₦ per kWh | Basis |
|---|---|---|
| Grid, Band A | 209.50 | NERC MYTO Nov 2025; 20+ hours promised; ₦160 for EEDC |
| Petrol generator, 2.5 kVA | 1.244 fuel / 1.431 with servicing | 1 L/h at 75% load (1.125 kWh/h), petrol ₦1.400/L, +15% oil and servicing |
| Petrol generator, 3.5 kVA | 1.333 / 1.533 | 1.5 L/h, 1.58 kWh/h |
| Petrol generator, 5 kVA | 1.493 / 1.717 | 2.4 L/h, 2.25 kWh/h |
| Diesel generator, 10 kVA | 1.439 / 1.655 | 3.5 L/h, 4.5 kWh/h, diesel ₦1.850/L gantry |
| Solar + LiFePO₄, 5 kVA, Lagos | 34–159 | Installed ₦2m–₦5.5m over 8–12 years, 1%/yr maintenance, 4.4 kWp at 3.63 kWh/kWp/day, 80–95% of output used |
What a generator really costs
kWh_per_hour = kVA × 0.8 × load_fraction a 2.5 kVA set at 75% load delivers 1.5 kWh/h
₦_per_kWh = Fuel_per_hour ÷ kWh_per_hour
Annual_₦ = Fuel_per_hour × hours_per_day × 365 × 1.15 +15% oil, plugs, servicing, wear (ZEUS assumption)
| Generator | Per hour | 4 h/day, year | 6 h/day, year | 10 h/day, year |
|---|---|---|---|---|
| 2.5 kVA petrol0.8–1.5 L/h, using 1 | ₦1,400 | ₦2.35m | ₦3.53m | ₦5.88m |
| 3.5 kVA petrol1.2–1.8 L/h, using 1.5 | ₦2,100 | ₦3.53m | ₦5.29m | ₦8.81m |
| 5 kVA petrol2.2–2.8 L/h, using 2.4 | ₦3,360 | ₦5.64m | ₦8.46m | ₦14.1m |
| 10 kVA diesel3–4.2 L/h, using 3.5 | ₦6,475 | ₦10.87m | ₦16.31m | ₦27.18m |
The other cost is availability: a generator delivers only while it runs, so a household running it six hours a night is still without power for the other outage hours, and a fridge that warms for eight hours a day is a food-loss line that never appears in the fuel budget.
What solar really costs
₦_per_kWh = (Capex ÷ life_years + Capex × 0.01) ÷ Annual_kWh_used
// ₦3.75m over 10 years: (₦375k + ₦38k) ÷ 5.247 = ₦79/kWh
Three things push the solar figure up: a battery replacement around year 8–12 (add ₦1m–₦3.5m once, which raises the ten-year figure by roughly ₦191–667/kWh); utilisation below 80% when the array is oversized for the load; and a Port Harcourt yield 6% below Lagos. Three things push it down: Kano-level yield (+28%), a tubular-free design with no mid-life bank replacement, and the fact that the panels are still producing at year 15 while the calculation stopped at 10.
What solar does not do is deliver 4 kW at 2 am in August from a 5 kWh battery. The honest comparison is solar for the base load and most evenings, with the generator kept for the rare long outage in the wet season; on that pattern generator hours fall by 80–90%, not 100%.
Payback
| Generator replaced | Hours/day | Annual cost | Payback at ₦2m | at ₦3.75m | at ₦5.5m |
|---|---|---|---|---|---|
| 2.5 kVA petrol | 4 | ₦2m | 1.0 | 1.9 | 2.8 |
| 2.5 kVA petrol | 6 | ₦3m | 0.7 | 1.3 | 1.8 |
| 2.5 kVA petrol | 10 | ₦5m | 0.4 | 0.8 | 1.1 |
| 5 kVA petrol | 4 | ₦4.8m | 0.4 | 0.8 | 1.1 |
| 5 kVA petrol | 6 | ₦7.19m | 0.3 | 0.5 | 0.8 |
| 10 kVA diesel | 6 | ₦13.86m | 0.1 | 0.3 | 0.4 |
Run your own hours, fuel price and system cost in the generator vs solar calculator.
Where the comparison is unfair
Unfair to the generator
- It provides full power on demand, day or night, in any weather; solar's evening power is limited by the battery.
- Its purchase price is a tenth of a solar system's, so the cash barrier is lower.
- Small sets are bought for surge loads (pumps, welding) that a 5 kVA inverter cannot start.
Unfair to solar
- The ten-year figure stops while the panels keep producing for 25.
- Fuel price risk sits entirely on the generator side: petrol rose from about ₦900/L in early 2026 to ₦1.400 by September.
- Noise, fumes, fuel theft and queueing are not priced.
- A Band A connection at ₦209.5/kWh is cheaper than solar per kWh only if the 20 hours are actually delivered.
The fair conclusion: for a household or small business currently burning fuel for four or more hours a day, a correctly sized solar-plus-lithium system at September 2026 prices pays for itself in two to four years and then produces electricity at a fraction of the grid tariff. For a Band A customer with reliable supply, solar is a backup purchase, not a savings purchase, unless the tariff keeps rising.
Solar arrays produce lethal DC voltages in daylight and cannot be switched off at the panel. Battery banks can deliver thousands of amps into a short circuit. Installation, wiring, earthing and commissioning must be done by a qualified installer or licensed electrician to the manufacturer's instructions and the Nigerian Electrical Installation Standards (IEC 60364-based). ZEUS explains how systems work so you can specify and check them, not so you can wire them yourself.
FAQ
How much does it cost to run a generator per day in Nigeria?
A 2.5 kVA petrol set burning 1 L/h for six hours at ₦1.400/L costs about ₦8,400 a day in fuel, ₦9,660 with servicing; roughly ₦3.53m a year. A 5 kVA set is about double.
What is the cost per kWh of generator electricity?
About ₦1.244–1.493 per kWh in fuel alone for 2.5–5 kVA petrol sets at 75% load and ₦1.400/L, versus ₦209.5 from a Band A grid connection. Part-load running makes it worse.
Is solar cheaper than NEPA (grid) power?
Per kWh over ten years, solar-plus-lithium (≈ ₦34–159) is close to or above the Band A tariff (₦209.5) and above Band B–E tariffs. Solar wins against the grid on availability, not price, unless tariffs rise further or the battery lasts beyond ten years.
How many years does a solar system take to pay back?
Two to four years if it replaces four or more generator hours a day at current fuel prices; longer for a Band A customer with good supply. See the table above and the calculator.
Sources
- Vanguard — Dangote adjusts petrol price to ₦1,350/L (12 Sep 2026) — www.vanguardngr.com/2026/09/dangote-adjusts-petrol-price-6-7-to-n1350-litre
- Nairametrics — petrol above ₦1,400/L as crude passes $100 (13 Sep 2026) — nairametrics.com/2026/09/13/petrol-rises-above-n1400-litre-as-crude-oil-climbs-past-100-per-barrel
- GlobalPetrolPrices — Nigeria gasoline ₦1,289.50/L (7 Sep 2026) — www.globalpetrolprices.com/Nigeria/gasoline_prices
- PM News — diesel from ₦1,800 to over ₦2,000/L (5 Sep 2026) — pmnewsnigeria.com/2026/09/05/diesel-price-spikes-from-n1800-to-over-n2000-litre
- NERC — Service Based Tariff bands (FAQ) — nerc.gov.ng/faq/electricity-tariffs
- BillsGuide.ng — Band A per DisCo, MYTO Nov 2025 (verified Apr 2026) — www.billsguide.ng/electricity-rates
- CBN NFEM closing rate (Vanguard, 15 Sep 2026) — www.vanguardngr.com/2026/09/dollar-to-naira-exchange-rate-today-september-15-2026
- Mercury Direct — Generator cost per hour vs inverter (2026) — mercurydirect.com.ng/generator-cost-per-hour-vs-inverter
- Lenol — The real cost of running a generator in Nigeria (2026) — lenol.co/blog/guides/cost-of-running-a-generator-in-nigeria
- SolarDecide — 5kVA system cost breakdown, Lagos/Abuja dealers (Apr 2026) — solardecide.com/blog/5kva-solar-system-cost-nigeria-2026
- Mercury Direct — 5kVA inverter guide, prices and batteries (2026) — mercurydirect.com.ng/5kva-inverter-guide-nigeria
- Kara.com.ng — 2026 solar price list (retailer blog) — blog.kara.com.ng/2026-solar-price-list-how-much-does-a-5kva-system-cost-in-nigeria-today
- Global Solar Atlas 2.0 — Lagos PVOUT (Solargis / World Bank) — globalsolaratlas.info