See how this project fits the wider market in our commercial solar Nigeria guide — SONCAP clearance, DisCo rules and a worked 500 kWp + 1 MWh diesel-replacement payback.
This commercial rice mill in Keffi ran huskers, pokers, polishers, and dryers on diesel generators for most of the day. Nigeria's grid could supply only a fraction of the mill's demand, and diesel at scale cost $5,000–11,000 every month depending on throughput and fuel prices.
Rice processing is energy-intensive: drying alone consumes vast thermal and electrical energy. The mill's profitability moved with diesel prices. Ownership needed to lock in a predictable energy cost and cut the logistics burden of constant fuel procurement.
Mars Solar engineered a solar power system with battery energy storage that runs the mill's full processing load on solar through the day and discharges stored energy into the evening shift. The 430kWh LFP battery bank replaced diesel as the primary energy reserve.
| Solar PV Capacity | 200 kW |
|---|---|
| Battery Energy Storage | 430 kWh LFP |
| Inverters | Hybrid, 3-phase |
| System Type | Hybrid: grid + solar + battery |
| Diesel displacement | Primary energy source replaced |
| Installation | 10 days, Mars Solar engineers on-site |
Monthly diesel power costs dropped by $5,000–11,000 — averaging $8,000+ in savings. Payback was confirmed at 14 months using the mill's actual electricity and fuel bills. The mill now runs a predictable energy cost and has expanded to a second processing line using the surplus solar capacity.
| Monthly savings | $8,000+ (diesel cost avoided) |
|---|---|
| Annual savings | $96,000+ |
| Payback period | 14 months (confirmed by bills) |
| Diesel dependence | Eliminated as primary source |
| Capacity headroom | Second processing line added |
“The numbers Mars Solar promised are the numbers we see on our bills. We recovered the investment in 14 months.”
— Owner, Keffi Rice Mill
Rice mills are the clearest diesel-replacement case in West Africa: huskers, polishers and dryers run all day, and generator fuel dominates running cost. A solar system for rice mill duty is sized from your motor list and drying load, not from available roof area, androof area, and the battery is specified to carry the evening shift. At this Keffi mill the 430kWh LFP bank took over from diesel as the primary reserve, turning a $5,000–11,000 monthly fuel bill into an $8,000+ monthly saving with payback confirmed at 14 months. If you are costing a solar system for rice mill, send us your load profile and your latest electricity or fuel bills — we return a sized design, a landed quote and a payback model within 24 hours.
The mill's problem was not grid electricity — it was diesel. Huskers, polishers and dryers ran on generators for most of the day, so the sizing exercise started from the generator log rather than from a utility bill: how many hours the gensets ran, at what load factor, and which motor starts happened at the same time.
Motor starting is what separateparates an agro-processing design from an office rooftop. Direct-on-line motor starts typically draw several times rated current for a few seconds — the industry rule of thumb is 5–7× — so the inverter and battery have to be specified for surge, not just for steady kW. 430 kWh was chosen to absorb those starts and cover the evening shift, and the design left headroom: a second processing line was added later without changing the power plant.
Yes, for the electrical load. Huskers, polishers, conveyors and dryers are motor loads; the design issue is starting surge and simultaneity, not steady-state power.
Displaced diesel. Before the project the mill was spending roughly $5,000–11,000 a month on fuel depending on throughput and fuel price. The published result is $8,000+ a month avoided and payback in 14 months, confirmed against t the mill's own records.
Yes, as a reserve for consecutive low-irradiance days and for simultaneous motor starts beyond the inverter's surge rating. What changed is its role: from primary source to backup, with far fewer annual service hours.
The system was built with headroom and a second line has since been added. If a future expansion exceeds that headroom, the array and inverter cabinet are the parts that grow; the battery usually does not need to change.
Against the site's own diesel purchase records and generator hours, not against a modelled tariff. The 14-month figure is the one the mill's bills support.
If your load is a mill, a feed plant or a cold room, a daytime-first design usually p pays back faster than a general commercial system. Read How agro-processing sites size PV and battery around the daytime load — load profiles, 2026 cost ranges and the SONCAP import steps.
Free system design and ROI estimate within 24 hours — based on your actual electricity bills.