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Solar savings calculator

How much can solar save you?

Enter your current electricity bill and we'll estimate the right system size, installation cost, government subsidy, and your payback period.

Based on Tamil Nadu solar irradiance · 2024 market rates · PM Surya Ghar subsidy included

Your details

TNEB domestic avg: ₹5–7

Assumptions

Peak sun hours: 5.5 hrs/day (Tamil Nadu average) · System efficiency: 77% · Panel: 550 Wp · Install cost: ₹62,000/kW · Subsidy: 30% capped at ₹78,000 · Degradation: 0.7%/year · Grid emission factor: 0.82 kg CO₂/kWh. Actual figures vary by roof orientation, shading, and current market rates.