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Free tool

Commercial Solar Payback Calculator

Running your business on diesel? Enter your monthly diesel spend and generator hours to see what a solar-hybrid system would cost, how fast it pays for itself, and what you would save over five years — built for Nigeria and Egypt.

Enter your monthly diesel spend and generator hours to see your estimate.

Is your business solar-ready?

You don't need a feasibility study to know whether solar is worth exploring. If these three things are true, the economics almost always deserve a serious look:

  • Your diesel bill is a line item management already complains about — for most businesses that means the generator runs 6+ hours a day.
  • A good share of your generator runtime happens during daylight, when solar generates directly and storage needs stay modest.
  • You have usable roof space or open ground — roughly 5 m² per kWp of solar capacity.

How the calculator works

The estimate works backwards from the one number every business knows precisely: what you pay for diesel. From your monthly spend it derives litres burned and energy generated (a typical commercial generator needs about 0.3 litres per kWh), then splits that energy by your generator hours: runtime falling in daylight is served by solar directly, while anything beyond it must cycle through battery storage — which is why a 24/7 operation needs a bigger investment than a daytime one. The system is priced at current installed costs for commercial projects in West and North Africa, including fixed project costs and economies of scale on larger systems.

Payback compares that investment against the diesel you stop buying, with fuel price escalation and system maintenance included. Every assumption is editable — engineers are welcome to disagree with our defaults.

Frequently asked questions

How accurate is this calculator?

It is a preliminary estimate built on typical generator fuel consumption (about 0.3 litres per kWh), local peak sun hours, and current installed costs for commercial solar and storage. Every assumption is visible and editable. A real proposal needs a site survey and measured load profile — which is exactly what MIMAH provides next.

What payback period should a business in Nigeria expect?

At post-subsidy diesel prices, most businesses see paybacks of roughly 2.5 to 5 years. Daytime-heavy operations land at the fast end because solar serves the load directly and storage stays small; 24/7 operations take longer because overnight energy needs substantial battery capacity. Larger diesel bills also pay back faster, since fixed project costs spread over a bigger system.

Does solar replace my generator completely?

Usually not immediately. A well-sized hybrid system typically replaces 60–90% of generator energy, with the generator retained for backup. The calculator lets you adjust this share and see how it changes the payback.

Is my business solar-ready?

Three quick signals: you spend a meaningful amount on diesel every month, your generator runs during daylight hours, and you have usable roof or ground space. If all three are true, solar is very likely worth a feasibility study.