What determines rooftop solar cost in India?
There is no single correct per-kW price for every roof. Project cost changes with module and inverter selection, mounting structure, roof height and access, cable routes, earthing and lightning protection, sanctioned load, net-metering scope, logistics and site-specific civil or electrical work.
A useful comparison must evaluate the complete commissioned scope—not only the module price. The Navonax calculator therefore lets you adjust system cost while showing the effect on payback and long-term value.
Size the system from consumption and usable roof area
Monthly electricity spend is converted into estimated annual consumption using the tariff you enter. The recommendation is then checked against available shadow-free roof area and regional solar yield. This prevents an attractive but impractical estimate from becoming the starting point.
Final design must also consider daytime consumption, export rules, sanctioned load, shading, roof condition and the local DISCOM process.
Subsidy, savings and payback should be shown separately
Eligible residential consumers may receive central financial assistance under PM Surya Ghar. The official National Portal states ₹30,000 per kW up to 2 kW, with total central subsidy capped at ₹78,000 for systems above 3 kW. Eligibility remains subject to current scheme, DCR, portal and DISCOM requirements.
Commercial and industrial systems are evaluated primarily through avoided electricity cost, demand profile, depreciation and financing—not residential subsidy.
How to compare two solar proposals
- Compare system capacity, module and inverter makes and warranty terms.
- Check structure material, wind design, earthing, protection and cable scope.
- Confirm net-metering, documentation, testing and commissioning responsibility.
- Compare realistic generation assumptions—not only an optimistic savings number.
- Review O&M, monitoring, service response and exclusions.