How much will solar save you?
Drag the sliders to your monthly KSEB consumption and available rooftop. We'll size the right system using the actual 2025-26 tariff slabs and show your payback in years, not decades.
The numbers behind your estimate
Telescopic vs non-telescopic: Below 250 bimonthly units, KSEB bills you slab-by-slab — only the units in each band pay that band's rate. Cross 250 units and you switch to a non-telescopic flat rate applied to every unit, which can nearly double the bill. Solar pays back fastest right at this threshold.
Peak sun hours: Kerala averages 5.5 peak sun hours per day. The calculator assumes 80% system efficiency (accounting for inverter losses, panel temperature, soiling, and orientation). Generation = systemKw × 5.5 × 30 × 0.8 per month.
Payback assumptions: Installed cost uses ₹60,000/kW for on-grid and ₹95,000/kW for hybrid. Annual savings × payback years = installed cost. Subsidy (up to ₹78,000 under PM Surya Ghar) is not included — adding it typically cuts payback by 12–18 months.
It uses the official KSEB LT-1A domestic tariff (2025-26) and Kerala-average solar irradiance (5.5 peak sun hours/day at 80% system efficiency). Real savings depend on roof orientation, shading, and consumption pattern. A free site survey gives an exact quote.
KSEB switches from telescopic (cheap slab-by-slab) to non-telescopic (single flat rate on all units) above 250 units bi-monthly. Crossing this threshold can nearly double your bill — and is exactly where solar pays back fastest.
Yes. The PM Surya Ghar subsidy of up to ₹78,000 (for 3 kW) is not included in the calculator output. Including it typically reduces the payback period by 12–18 months.
| Slab (units) | Rate / kWh |
|---|---|
| 0 – 50 | ₹3.25 |
| 51 – 100 | ₹4.05 |
| 101 – 150 | ₹5.10 |
| 151 – 200 | ₹6.95 |
| 201 – 250 | ₹8.20 |
| Bimonthly units | Flat / kWh |
|---|---|
| Up to 300 | ₹6.75 |
| 301 – 350 | ₹7.60 |
| 351 – 400 | ₹7.95 |
| 401 – 500 | ₹8.25 |
| 501+ | ₹9.20 |
Plus fixed charge (₹80 single / ₹220 three phase), fuel surcharge, electricity duty, and meter rent. All applied automatically in the calculator.