Solar Calculators for India
Two free tools that answer the questions that matter most: how large a system do I need, and will it be worth the investment?
Solar System Calculator
Start hereEnter your monthly electricity bill and instantly get your recommended system size in kW, installation cost estimate, and the exact PM Surya Ghar subsidy you qualify for.
then use your results in
Solar Savings Calculator
ROI & financialsHave a system size or vendor quote? Enter the kW capacity and electricity rate to get your exact payback year, 10-year and 25-year ROI, and total lifetime profit.
Which Calculator Should You Start With?
They work best in sequence, but each is useful on its own.
Use Solar System Calculator if…
- ●You're exploring solar for the first time
- ●You have your electricity bill handy
- ●You need a system size recommendation
- ●You want to know your subsidy eligibility
Use Savings Calculator if…
- ●You already have a system size or quote
- ●You want to verify the financial return
- ●You need the exact payback year
- ●You're comparing 10-year vs 25-year ROI
Why Two Separate Tools?
System sizing (how many kW?) is an engineering question based on your consumption and roof. Financial analysis (is it worth it?) is an investment question based on net cost and electricity escalation. Separating them gives you cleaner, more accurate answers for each. Both use conservative benchmarks — 4.5 peak sun hours/day nationally, ₹55,000–₹60,000/kW installation cost — so results are realistic, not optimistic.
What These Calculators Don't Replace
Online calculators are excellent for ballpark estimates and initial decision-making, but can't replace an on-site assessment. Roof angle, shading, and local vendor pricing all affect the final design and cost. After using our calculators, schedule a free site visit with a Solar Saathi verified vendor — they'll give you a binding written quotation.