Residential Rooftop Solar in India : Your complete guide

Going solar is one of the smartest decisions Indian homeowners can make today. With government subsidies covering a significant chunk of installation costs and electricity bills rising every year, rooftop solar has never been more accessible. This guide walks you through everything you need to know before installing solar panels on your home.

Understanding Your Solar Requirements

Before you start comparing quotes or filling out subsidy applications, you need to answer two fundamental questions:

1. Check Your Sanctioned Load

Your sanctioned load—mentioned on your electricity bill—determines the maximum solar capacity you can install under net metering rules. Most residential connections have a sanctioned load between 2 kW and 10 kW.

Where to find it: Look for "Sanctioned Load" or "Connected Load" on the first page of your electricity bill. It's usually listed in kW or kVA.

Why it matters: DISCOMs typically allow rooftop solar capacity up to your sanctioned load. If you want a larger system, you may need to apply for a load enhancement first.

2. Measure Your Available Roof Space

Solar panels need shadow-free space to perform efficiently. As a thumb rule:

System Size	Approximate Roof Area Required
1 kW	10–12 sq. metres
2 kW	20–24 sq. metres
3 kW	30–36 sq. metres
5 kW	50–60 sq. metres
10 kW	100–120 sq. metres

Tip: The area should be free from shadows between 9 AM and 4 PM. Shadows from water tanks, trees, adjacent buildings, or parapet walls can significantly reduce generation.

Types of Rooftop Solar Systems

On-Grid (Grid-Tied) Systems

On-grid systems connect directly to your electricity grid. They're the most popular choice for homes and the only type eligible for government subsidy.

How it works:

• Solar panels generate electricity during the day

• You consume what you need; excess is exported to the grid

• At night or during cloudy weather, you draw power from the grid

• Your meter runs backward when you export, reducing your bill (net metering)

Best for: Homes with reliable grid supply, those looking to maximise savings with subsidy support

Off-Grid Systems

Off-grid systems operate independently with battery storage. They're not connected to the grid.

How it works:

• Solar panels charge batteries during the day

• You use stored power round the clock

• No dependency on or interaction with the grid

Best for: Remote locations without grid access, farmhouses, or situations where complete independence from the grid is essential

Important: No government subsidy is available for off-grid systems.

Hybrid Systems

Hybrid systems combine the best of both worlds—grid connection plus battery backup.

How it works:

• Primarily operates like an on-grid system

• Batteries provide backup during power cuts

• Can be programmed to prioritize self-consumption or export

Best for: Areas with frequent power cuts, homeowners who want backup without sacrificing net metering benefits

Important: No government subsidy is currently available for hybrid systems.

DCR vs Non-DCR Solar Panels

This distinction is crucial when planning your installation.

DCR (Domestic Content Requirement) Panels

• Solar cells and modules manufactured in India

• Mandatory for availing government subsidy

• Slightly higher cost per watt compared to imports

• Quality has improved significantly in recent years

Non-DCR Panels

• Imported cells/modules (typically from China or Southeast Asia)

• Not eligible for any government subsidy

• Generally 15–25% cheaper per watt

• Wide variety of brands and efficiency ratings available

Which Should You Choose?

Scenario	Recommendation
System size up to 3 kW	Go DCR — Subsidy of ₹78,000 makes it significantly cheaper
System size 3–5 kW	Go DCR — Subsidy still offsets the price difference
System size above 5 kW	Consider Non-DCR — Subsidy is capped at ₹78,000, so the cost advantage of Non-DCR panels becomes meaningful at larger capacities

PM Surya Ghar Yojana: Central Government Subsidy

The central government's flagship rooftop solar scheme offers substantial subsidies for residential installations.

Subsidy Structure

System Capacity	Central Subsidy
1 kW	₹30,000
2 kW	₹60,000
3 kW and above	₹78,000 (capped)

Key points:

• ₹30,000 per kW for the first 2 kW

• ₹18,000 per kW for capacity between 2–3 kW

• Maximum subsidy capped at ₹78,000 regardless of system size

• Subsidy credited directly to your bank account after installation and inspection

Eligibility Criteria

• Indian citizen with a residential electricity connection

• Property must be in your name (or have owner's consent)

• No existing rooftop solar installation at the address

• System must be grid-connected (on-grid)

• DCR-compliant panels and BIS-certified inverter mandatory

• Installed by DISCOM-empanelled vendor

Application Process

1. Register on pmsuryaghar.gov.in using your electricity consumer number

2. Apply for feasibility approval from your DISCOM

3. Select an empanelled vendor and finalise the system design

4. Complete installation; vendor uploads commissioning report

5. DISCOM inspects and approves the installation

6. Apply for net meter installation

7. Subsidy is transferred to your bank account via DBT (typically within 30 days of final approval)

Key Takeaways

1. Start with basics — Know your sanctioned load and available roof space before anything else

2. On-grid is the way to go for most homes — it's the only type eligible for subsidy

3. DCR panels are mandatory for subsidy; Non-DCR makes sense only for systems above 5 kW where the cost savings outweigh the lost subsidy

4. Central subsidy is ₹78,000 max for systems 3 kW and above

5. Check for state top-ups — some states offer significant additional support

6. Use empanelled vendors only — this is required for subsidy and ensures accountability