A credible solar ROI starts with interval-aware consumption
Commercial solar economics depend on when electricity is consumed—not only the monthly bill. Daytime load, working days, seasonal operations, tariff category, demand charges, export settlement and sanctioned load determine how much solar generation can be used effectively.
An initial calculator estimate is useful for screening. Investment approval should use at least 12 months of bills and a site-specific generation simulation.
Inputs that materially change commercial payback
- Delivered EPC cost and taxes.
- Annual specific generation and system losses.
- Self-consumption and export assumptions.
- Applicable energy tariff and realistic tariff escalation.
- O&M, insurance, degradation and inverter lifecycle assumptions.
- Debt share, interest rate, tenure and tax treatment.
Evaluate cash purchase and finance separately
Simple payback helps compare projects, but financed projects also need annual cash flow, EMI or debt service, interest cost and the timing of tax benefits. A proposal should state every assumption and show how results change when generation or tariff growth is lower than expected.
The Navonax calculator provides an editable planning view; a detailed proposal can then model the actual facility, tariff and financing structure.
What Navonax verifies before a bankable proposal
Our engineering review covers roof and structure, electrical single-line requirements, evacuation route, transformer and sanctioned load, protection, earthing, monitoring, shutdown constraints, execution phasing and applicable approvals.
For hospitals, hotels, educational institutions and industrial facilities, continuity, safety and coordinated installation planning are treated alongside financial return.