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Solar calculators for Indian rooftop planning

Estimate rooftop solar capacity, panels, cost, subsidy context, savings and payback with clear assumptions.

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Rooftop Solar Panel Calculator India

Start with the information on your electricity bill

Rooftop solar planning is easier when the first estimate uses information a household can actually find. Enter a typical monthly electricity bill, then adjust the editable planning tariff to match the unit cost shown by your electricity provider. A bill can include fixed charges, taxes, arrears, seasonal changes, and slab pricing, so a bill-to-units estimate is not the same as a meter reading. If your bill shows monthly units, compare that value with the calculator estimate and use the more reliable figure for later planning.

State and customer category change the context

Choose the State or Union Territory and the customer category before interpreting the result. Residential homes, apartments or RWAs, commercial premises, and industrial connections can have different tariffs, approvals, subsidy eligibility, load requirements, and net-metering rules. The calculator keeps these choices visible so a residential central-assistance estimate is not mistaken for a commercial benefit. State selection provides planning context; it does not replace the current DISCOM tariff order or an official subsidy decision.

Treat the result as an early rooftop estimate

The Rooftop Solar Calculator estimates system size, panel count, annual generation, roof area, cost, savings, and a simple payback signal from the values entered. It uses illustrative planning assumptions for early comparison, not a site-specific engineering model. Shade, roof orientation, structure, panel technology, inverter choice, wiring, installation, GST, export credits, maintenance, downtime, and local approval can change the final result. Use the output to prepare questions for a qualified installer or engineer. Confirm current PM Surya Ghar rules and State or DISCOM requirements through official sources before making a purchase or relying on a subsidy amount. The calculator is useful for comparing scenarios, such as a 50%, 80%, or 100% bill-offset target, but a larger target is not automatically possible on every roof. Keep the inputs and assumptions with any result you share. Keep a dated copy of the bill, tariff assumption, roof measurement, installer proposal, and official eligibility information so later comparisons explain why numbers changed. This is especially important when electricity prices, equipment costs, or government programmes are revised.