Enter the units you use a month and your vendor's price to see the PM Surya Ghar subsidy, the system size you need, how much it generates, your bill savings, the payback time and the loan EMI, for a home or a housing society.
How to use the rooftop solar calculator
- Choose a home or a housing society, and tick the box if you're in a special-category state or UT.
- Enter your monthly units from the electricity bill, the system size (or tap the suggested size) and the cost per kW from your vendor.
- Open the extra options for your tariff, a state subsidy and a scheme loan, then read the subsidy, savings and payback.
Worked example
A home uses 300 units a month and installs 3 kW at ₹60,000 a kW: ₹1,80,000. The central subsidy is ₹30,000 × 2 + ₹18,000 = ₹78,000, so it costs ₹1,02,000. At 4 units a day per kW it makes 4,380 units a year: 3,600 replace units bought at ₹7 and 780 surplus units earn ₹3, saving ₹27,540 a year and paying back in about 3.7 years.
How it's worked out
- Subsidy (homes): ₹30,000 per kW up to 2 kW + ₹18,000 for the third kW, at most ₹78,000
- Generation = kW × units per kW per day × 365
- Savings = units you use × your tariff + surplus units × the surplus rate
- Payback = cost after subsidy ÷ yearly savings
Source: PM Surya Ghar: Muft Bijli Yojana, Cabinet approval (PIB, 29 February 2024) and scheme guidelines. Apply on pmsuryaghar.gov.in. Everything runs in your browser.
Frequently asked questions
How much subsidy does PM Surya Ghar give?
For homes, the central subsidy is ₹30,000 per kW for the first 2 kW and ₹18,000 for the third kW: ₹30,000 for 1 kW, ₹60,000 for 2 kW and ₹78,000 for 3 kW or more. In special-category states and UTs (Uttarakhand, Himachal Pradesh, Jammu & Kashmir, Ladakh, the North-East including Sikkim, Andaman & Nicobar and Lakshadweep) it's ₹33,000 and ₹19,800 per kW, up to ₹85,800. Some states add their own subsidy on top.
What size of solar system do I need?
A 1 kW rooftop system makes about 4 units a day, roughly 120 units a month, so divide your monthly units by about 120. A home using 300 units a month needs about 2.5 kW; 360 units, about 3 kW. Since the subsidy stops growing at 3 kW, homes using up to about 360 units a month get the most subsidy for their size.
What about housing societies and RWAs?
Group housing societies and resident welfare associations get ₹18,000 per kW (₹19,800 in special-category states) for common facilities such as lifts, corridor lights, water pumps and EV charging, up to 500 kW, counted at 3 kW per house including any plants residents have installed themselves.
How much will I save, and when does it pay back?
Every unit the panels make replaces a unit you'd buy, at your tariff; units left over at the end of the year are paid at your DISCOM's rate under net metering. A 3 kW system at ₹60,000 a kW costs ₹1,80,000, or ₹1,02,000 after the ₹78,000 subsidy. Making about 4,380 units a year for a home using 300 units a month at ₹7 a unit, with surplus paid at ₹3, it saves about ₹27,540 a year and pays back in about 3.7 years.
Can I get a loan for rooftop solar?
Yes. Public-sector banks offer collateral-free loans under the scheme at about 7% for systems up to 3 kW; your bank sets the exact rate and term. ₹1,02,000 over 10 years at 7% is an EMI of about ₹1,184, below the ₹2,295 a month the example system saves.
