Solar Saathi
Solar Saathi
Home

Core Services

Solar ConsultancyTechnology ConsultationSite Visit & SurveyVendor SelectionPerformance Advisory

By Property Type

Residential SolarCommercial SolarIndustrial SolarInstitutional Solar
Solar CalculatorSavings CalculatorTilt Angle CalculatorAll Tools
Become a PartnerBlogsAbout Us
LoginGet Free Consultation →
🧮 Free Solar Tools

Solar Calculators for India

Three free tools that answer the questions that matter most before installing solar — system size, financial return, and panel angle.

☀️

Solar System Calculator

Start here

Enter 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.

kW system sizeInstallation cost rangePM Surya Ghar subsidyFree site visit
Open Calculator

then use your results in

💹

Solar Savings Calculator

ROI & financials

Have 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.

Payback year10-year ROI25-year ROILifetime profitCO₂ offset
Open Calculator

also useful before installation

📐

Solar Panel Tilt Angle Calculator

Installation guide

Find the ideal tilt angle for your solar panels based on your city or state in India. Includes summer and winter seasonal adjustments, mount type guidance, and orientation tips.

40+ citiesAll 36 states & UTsSeasonal anglesMount type guideRoof spacing note
Open Calculator

Which Calculator Should You Use?

They work best in sequence, but each is useful on its own.

☀️ Solar System Calculator

  • ●You're exploring solar for the first time
  • ●You want a system size recommendation
  • ●You need your subsidy eligibility

💹 Savings Calculator

  • ●You already have a system size or quote
  • ●You want exact payback year and ROI
  • ●You're comparing 10-year vs 25-year returns

📐 Tilt Angle Calculator

  • ●You're planning panel placement or direction
  • ●You want seasonal angle adjustments
  • ●You're comparing fixed vs adjustable mounts

Why Three Separate Tools?

System sizing (how many kW?), financial analysis (is it worth it?), and installation geometry (what angle?) are three distinct questions that need their own clean answers. Combining them produces confusion. Separating them gives you accurate, actionable numbers at each stage of your decision — from initial curiosity to installation planning.

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, local vendor pricing, and structural constraints all affect the final design and cost. After using our calculators, schedule a free site visit with a Solar Saathi verified expert — they'll give you a binding written quotation.

Frequently Asked Questions

Are these solar calculators free?
Yes, completely free. The Solar System Calculator asks for basic contact details so our verified vendors can follow up with a quote if you want one. The Savings Calculator and Tilt Angle Calculator require no contact information at all.
How accurate are the estimates?
Within 10–20% of actual vendor quotes for most locations. Always compare 2–3 quotes from verified vendors before making a decision.
Does the system size calculator include PM Surya Ghar subsidy?
Yes. Both the Solar System Calculator and Savings Calculator apply the central PM Surya Ghar Muft Bijli Yojana subsidy — ₹30,000/kW for the first 2 kW, ₹18,000 for the third kW, and ₹9,000/kW beyond 3 kW — for residential systems.
Can I use the calculators for commercial solar?
Yes, all three support residential, commercial, and industrial property types. The PM Surya Ghar subsidy only applies to residential consumers; commercial systems get accurate cost estimates without the subsidy deduction.
What is the ideal solar panel angle in India?
It equals your geographic latitude. Delhi (~28.6°N) → ~28–30°, Mumbai (~19.1°N) → ~19–20°, Chennai (~13°N) → ~13–15°, all facing true south. Use the Tilt Angle Calculator for your exact city or state.
What's the difference between all three calculators?
The Solar System Calculator takes your monthly bill and tells you what size solar system you need and what it costs. The Savings Calculator takes that system size and tells you the exact financial return. The Tilt Angle Calculator tells you how to physically orient and angle your panels for maximum output.