Compare rooftop solar and small wind turbine ROI side-by-side. Enter your TANGEDCO bill, system size, and cost — get instant payback period, net savings, and 10-year cumulative trend for your Chennai property.
⏱️ How to use (1–2 mins)
- Enter monthly bill & average rate (optional)
- Choose system sizes & capacity factors
- Enter installed costs & O&M estimates
- Click Calculate ROI to see savings, payback & trend chart
- Tip: Wind performance is highly site- & height-dependent.
📈 ROI Comparison Results
Estimates based on your inputs · Chennai TANGEDCO tariff data · Not a guaranteed quote
Solar
Wind
📊 Cumulative Net Savings Over 10 Years
| Metric | ☀️ Solar | 💨 Wind |
|---|---|---|
| System size | — | — |
| Annual generation | — | — |
| Installed cost | — | — |
| Annual O&M | — | — |
| Payback period | — | — |
| Net savings (10 yr) | — | — |
| Bill offset % | — | — |
📩 Get a Customised ROI Plan for Your Property
Share your number and we’ll review your inputs, factor in TANGEDCO net-metering and applicable subsidies, and suggest the best-fit configuration for your Chennai site — free.
- Annual Generation: kW × 8,760 hrs × (CF ÷ 100)
- Monthly Bill Offset (kWh): (Annual Generation × Self-Consumption%) ÷ 12, capped at monthly consumption
- Year 1 Savings (₹): Monthly Offset × Electricity Rate × 12 − Annual O&M
- Tariff Escalation: Applied compounded annually to savings value
- Cumulative Net Savings: Sum of annual savings over the horizon
- Payback: Simple (cost ÷ average annual net savings) — no financing, no depreciation
• Rooftop solar output depends on roof orientation, shading, and panel quality. North-facing installations underperform by 15–25%.
• Small wind turbines (1–5 kW) are only viable at Chennai coastal sites with consistent wind speeds >4 m/s at hub height. A site assessment is essential.
• This calculator does not model TANGEDCO net-metering, PM Surya Ghar subsidy (₹18,000–₹78,000), TANGEDCO banking, or battery storage.
• Results are rough estimates only — not a guaranteed quote.
FAQ
Solar: 1–10 kW rooftop. Wind: 1–3 kW small turbines.
Wind output varies heavily with height & local conditions. CF models this transparently.
Intentionally generic. NST can model precise subsidy/export benefits after consultation.
No. It’s an estimate. Actual performance depends on installation quality & maintenance.