Installing rooftop solar involves seven clear steps: checking your roof, sizing your system, picking a certified installer, getting permits, completing installation, passing inspection, and activating net metering. In India, most homes go from first inquiry to full grid connection in 60 to 90 days. The government's PM Surya Ghar scheme offers subsidies of up to Rs. 78,000, making this one of the smartest home investments you can make right now.
Your electricity bill arrives every month. You look at the number, feel that familiar sting, and tell yourself: "I should really do something about this." You've heard about rooftop solar installation. You've seen the panels on your neighbour's roof. But you still don't know exactly how it all works. What are the steps? Who handles the paperwork? How long does it take? And is the government subsidy real or just another promise on paper?
The truth is, rooftop solar is not complicated. It just feels that way because no one walks you through the full picture in one place. This guide does exactly that. You'll get a clear, step-by-step view of the entire installation process, from checking if your roof is ready all the way to the day your meter starts spinning backward.
India is already the world's third largest solar energy producer, with installed solar capacity crossing 119 GW as of July 2025. This is your moment to be part of it. Let's break it all down.
Step 1: Is Your Roof Ready for Solar?
Direct Answer: A roof is solar-ready if it is less than 10 years old, faces south or southwest, is free from major shading, and can handle an additional load of around 15 to 20 kg per square metre. If your roof fails any of these checks, fix it first before going solar.
Most homeowners skip this step and jump straight to calling an installer. That's a mistake. Your roof's condition directly affects how much power your system produces and how long it lasts.
What to check before anything else:
Roof age and condition: If your roof is older than 10 years or has cracks, fix it first. You don't want to undo solar panels six months after installation for a repair job.
Orientation: In India, a south-facing roof receives maximum sunlight throughout the year. South-west works well too. North-facing roofs are generally not ideal.
Shading: Trees, water tanks, neighbouring buildings, and overhead cables all reduce output. Even a small shadow on one panel can affect the whole system.
Available area: You need roughly 8 to 10 square metres of clear, unshaded space for every 1 kW of panels you install.
Structural strength: Solar panels and the mounting structure add weight. Your roof must be able to handle it. An installer will check this during the site survey.
Quick Tip: The 20% rule is a useful guideline. Keep at least 20% of your rooftop clear for safety and maintenance access. Don't fill every inch with panels.
Step 2: How Much Solar Capacity Do You Actually Need?
Direct Answer: Divide your average monthly electricity consumption (in units or kWh) by 120 to get an approximate system size in kW. For example, if you use 300 units per month, you need roughly a 2.5 kW system. A typical 3BHK home with one air conditioner usually needs 3 kW to 4 kW.
Sizing is the most important decision you'll make. Too small and you'll still pay high bills. Too large and you'll spend more than you need to.
How to calculate your system size:
Step 1: Look at your electricity bill. Find your monthly consumption in units (kWh). Take an average of the last 6 months.
Step 2: Divide that number by 120 (this accounts for about 4 peak sun hours per day over 30 days).
Step 3: The result is your approximate system size in kW. Add a small buffer of 10 to 20% if your usage is growing.
Example: Monthly usage = 400 units. 400 / 120 = 3.3 kW. Round up to a 3.5 kW or 4 kW system.
Which system type is right for you?
On-grid system: Connected to your DISCOM's power grid. Excess power is exported and you earn credits through net metering. No battery needed. This is the most common choice for urban homes.
Off-grid system: Fully independent. Needs a battery bank. Suitable if you face frequent power cuts and no reliable grid connection.
Hybrid system: Combines both. Grid-connected but also has battery backup for cuts. More expensive, but ideal if outages are a daily problem in your area.
You can use MNRE's free online solar calculator at pmsuryaghar.gov.in to estimate the right capacity based on your roof area and electricity usage.
Step 3: Finding and Vetting a Certified Solar Installer
Direct Answer: Always hire an MNRE-empanelled vendor registered on the National Rooftop Solar Portal. This is not optional. If your installer is not on this list, you will not qualify for the PM Surya Ghar subsidy of up to Rs. 78,000.
Picking the right installer is as important as picking the right panels. A poor installation creates problems that no amount of quality equipment can fix. India's PM Surya Ghar scheme has already crossed 10 lakh installations, and the most common issue for rejected subsidies is unapproved vendors.
How to find a certified installer:
Visit pmsuryaghar.gov.in and search for approved vendors in your area.
Check your state DISCOM's empanelled vendor list as well, since some state subsidies require state-specific approvals.
Read Google Reviews and ask for references from past residential installations.
Questions to ask before you sign anything:
How many residential installations have you done in this area?
What brands of panels and inverters do you use, and what are the specifications?
Do you handle the subsidy paperwork and DISCOM applications?
What does the warranty cover, and who do I call if something goes wrong after installation?
Is the price quote itemised? I want a breakdown of panels, inverter, mounting, and labour costs.
Red Flag: Any installer who gives you a verbal quote without a written breakdown or discourages you from applying for a subsidy is not someone you want working on your roof.
Step 4: Permits, Subsidies, and Net Metering Application
Direct Answer: Your installer typically handles most of this paperwork. But you must personally apply on the PM Surya Ghar portal (pmsuryaghar.gov.in) to get your subsidy approved before installation begins. Do not let the installer skip the portal registration step.
This is the step most homeowners find confusing. Let's simplify it.
The PM Surya Ghar subsidy: what you actually get
Under the PM Surya Ghar Muft Bijli Yojana, the central government offers a direct subsidy to your bank account:
1 kW system: Rs. 30,000 subsidy
2 kW system: Rs. 60,000 subsidy
3 kW system and above: Rs. 78,000 subsidy (maximum)
Many high-support states like Gujarat, Maharashtra, and Rajasthan add their own subsidies on top of the central amount, so your actual benefit could be higher. The subsidy is deposited directly to your bank account within 30 days of commissioning.
How to apply on the PM Surya Ghar portal:
Visit pmsuryaghar.gov.in and register with your mobile number.
Enter your electricity consumer number from your bill.
Apply for Rooftop Solar and wait for DISCOM feasibility approval.
Once approved, select an empanelled vendor and submit your bank details.
After installation and DISCOM inspection, the subsidy is transferred within 30 days.
What is net metering and why does it matter?
Net metering is the system that lets you sell excess solar power back to the grid. Your electricity meter becomes bidirectional. It records both what you consume from the grid and what you export to it. At the end of the month, you only pay for the net difference.
This is what makes on-grid solar so financially attractive. Homeowners can earn Rs. 17,000 to Rs. 18,000 per year by selling surplus power to the grid.
Approval Timeline: DISCOM net metering approval typically takes 20 to 40 days if your documents are complete. Missing documents are the most common reason for delays. Keep your electricity consumer number, ID proof, address proof, and property documents ready.
Step 5: What Happens During the Actual Installation?
This is the part that looks the most complex but is actually the most straightforward. A typical residential installation takes 1 to 3 days, depending on the system size.
Day 1: Mounting structure
The installation team starts by fixing the mounting structure to your roof. This is the metal frame that holds your panels at the right angle and keeps them firmly in place. The tilt is usually set at the angle equal to your city's latitude for maximum sunlight capture throughout the year.
For flat roofs, adjustable aluminium mounting structures are used. For sloped roofs, rails are attached along the existing slope. Make sure the team checks that drilling points avoid water pipes and cables hidden in the roof slab.
Day 1 to Day 2: Panel placement and electrical wiring
Solar panels are placed onto the mounting structure and secured. The team then connects the panels together in a configuration (called strings) that matches your inverter's input requirements.
Wiring runs from the panels down to the inverter, which is usually mounted on a wall near your main electrical panel. The inverter converts DC power from the panels into AC power that your home appliances can use. Earthing wires and surge protection devices are also installed at this stage. These are not optional extras; they protect your system from lightning and voltage spikes.
Day 2: Final connections and testing
The inverter is connected to your home's electrical panel. The installer tests the system end-to-end: panel output, inverter readings, and safe disconnection switches. You should see numbers on the inverter display showing live power generation.
Do NOT skip this: Ask the installer to walk you through what to check on the inverter display and how to use the monitoring app before they leave. A good installer sets this up for you.
Step 6: Inspection, Grid Connection, and Commissioning
Direct Answer: After installation, your DISCOM sends an engineer to inspect the system. If it passes, they install a bidirectional meter and issue a commissioning certificate. Net metering becomes active and your solar journey officially begins.
This is the final approval stage and it's handled between your installer and the DISCOM. Your job is to make sure someone is home on the day of inspection.
What the DISCOM inspector checks:
Panel placement and mounting structure stability
Inverter make, model, and compliance with BIS and MNRE standards
Earthing and safety switch installation
AC and DC wiring quality and insulation
System capacity matching the approved application
If everything is in order, the DISCOM replaces your single-direction meter with a bidirectional meter. This is the meter that tracks both your import from the grid and your export to it.
After the bidirectional meter is installed, the commissioning certificate is generated through the national portal. Once you upload this and your bank details, the subsidy is released within 30 days.
Timeline Expectation: Most residential systems achieve full grid connection within 60 to 90 days from the first application. The DISCOM inspection and meter installation is usually the longest wait, averaging 20 to 40 days depending on your state.
Step 7: Monitoring, Maintenance, and Maximising Your Savings
Your system is live. Your first electricity bill post-solar will feel like a pleasant surprise. But to keep savings high for the full 25-year life of your system, a little attention goes a long way.
Set up your monitoring app
Most modern solar inverters come with a companion app. This app shows you real-time generation data, daily totals, monthly output, and alerts for any faults. Check your app every few days in the first month to understand your system's normal behaviour.
A healthy 3 kW system in most Indian cities should generate around 360 to 420 units of electricity per month, varying slightly by season.
Maintenance: less than you think
Cleaning: Dust is the biggest reducer of output in Indian conditions. Clean panels every 4 to 6 weeks in dusty cities. Use soft cloth and plain water. No harsh chemicals.
Annual inspection: Get a professional to check the inverter, wiring connections, and mounting bolts once a year.
Inverter: Inverters typically last 10 to 15 years and may need replacement once during your system's 25-year life.
Warranty: Solar panels usually come with a 25-year performance warranty guaranteeing at least 80% output. Keep all warranty documents safely.
Understanding your new electricity bill
With net metering active, your bill will show two figures: units imported from the grid and units exported to the grid. You pay only for the net consumption. During peak summer months when your panels generate more than your usage, your bill may be zero or you'll accumulate credits.
Most homeowners in India recover their solar investment in 4 to 6 years through savings on electricity bills. After that, the next two decades of generation are essentially free electricity.
The Bottom Line
Installing rooftop solar at home is a seven-step process that follows a clear sequence. You start by checking your roof, size your system based on your electricity consumption, choose an MNRE-certified installer, complete the paperwork for subsidies and net metering, get your panels installed in 1 to 3 days, pass the DISCOM inspection, and then sit back and watch your electricity bill drop.
The PM Surya Ghar scheme makes this more affordable than it has ever been. Over 10 lakh homes are already solar-powered across India. The process is clear. The savings are real. The only question is how long you'll wait before starting.
Start with Step 1 today. Look at your last six electricity bills, find your average monthly consumption, and visit pmsuryaghar.gov.in to explore your subsidy eligibility. Once you know your numbers, everything else falls into place.
Frequently Asked Questions
How long does rooftop solar installation take from start to finish?
From your first application on the national portal to full grid connection, most residential systems are operational within 60 to 90 days. The physical installation itself takes just 1 to 3 days. The longer wait is usually for DISCOM feasibility approval and meter installation, which averages 20 to 40 days depending on your state's workload.
Can I install rooftop solar on a rented home?
Technically yes, but you'll need written permission from the property owner. The subsidy and net metering connection are tied to the electricity consumer number, which is typically in the landlord's name. This can create complications. Most solar financiers and installers recommend the property owner drives the installation for a clean legal and subsidy structure.
What subsidies are available for rooftop solar in India in 2025?
Under the PM Surya Ghar Muft Bijli Yojana, the central government offers Rs. 30,000 for a 1 kW system, Rs. 60,000 for 2 kW, and Rs. 78,000 for 3 kW and above. Several states including Gujarat, Maharashtra, and Rajasthan offer additional state-level subsidies. Collateral-free loans up to Rs. 2 lakh are also available at a subsidised 6.75% interest rate through public sector banks.
What happens to my solar system during a power cut?
For on-grid systems without a battery, your solar panels automatically shut off during a power cut. This is a safety requirement to protect DISCOM engineers working on the lines. If you need power during outages, you'll need a hybrid system with battery storage. Off-grid systems with batteries work independently and are not affected by grid outages.
How do I know if my solar panels are performing correctly after installation?
Your inverter display and monitoring app are your best tools. Check that your system generates roughly 3.5 to 4.5 units per kW of installed capacity per day in clear weather. If output drops significantly on a sunny day, the likely causes are dust accumulation on panels, a shading issue, or an inverter fault. Your installer's after-sales team should be the first call in that scenario.
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