Residential Rooftop Solar
Turn Your Rooftop Into an Energy Asset.
01Overview
What Rooftop Solar Actually Does.
A rooftop system generates electricity during daylight hours. What your home uses at that moment comes from the array; what it does not use is exported to the grid, and what the array cannot supply is drawn from the grid as before.
Your bill reflects the net position across the billing period, under the net-metering arrangement that applies to your connection. That is why consumption pattern matters as much as total consumption: electricity used during the day displaces purchased units directly.
Everything else — sizing, configuration, whether a battery makes sense — follows from that basic picture and from the particulars of your roof.
02Roof Suitability
Your Roof Sets the Limit.
Before any system size is discussed, the roof has to be understood. This is the part that most often changes the answer.
- Shadow-free area
- Not the total roof, but the part that stays clear of shade through the day and across the year. Parapets, water tanks, stair rooms, neighbouring buildings and trees all take their share.
- Orientation and tilt
- Which way the usable area faces and at what pitch. A flat roof gives more freedom to orient the array than a steeply pitched one.
- Structure and condition
- The roof carries the array, its mounting and wind load for decades. RCC slabs, sheet roofs and tiled roofs each need a different approach.
- Access and routing
- Safe access for installation and cleaning, and a sensible cable route from the array to the inverter and the meter.
- Future plans
- An additional floor, a new water tank or a planned extension will affect an array installed today. Worth raising before, not after.
03System Sizing
Three Numbers Decide the Size.
Your consumption across twelve months, not one. A single summer bill will oversize a system; a single monsoon bill will undersize it.
Your usable roof area after shading, access paths and existing structures are taken out. This frequently caps the system below what consumption alone would suggest.
Your sanctioned load, which the distribution company’s rules relate the permitted system capacity to.
Where these three disagree, the smallest wins. A proposal that ignores two of them is not a proposal, it is a price list.
04Configuration
On-Grid, Hybrid or Off-Grid.
Most homes with a reliable connection are best served by an on-grid system. The others solve a different problem, at a different cost.
- On-grid (grid-tied)
- Works alongside your utility supply, with a net meter recording what you export and import. No battery. The most common residential choice, and the configuration the residential scheme is built around. It does not run during a grid outage.
- Hybrid
- Grid-connected with battery storage, so selected circuits keep running through an outage. Higher cost and added maintenance, and the battery has its own replacement cycle. Suited to homes with frequent or long outages.
- Off-grid
- Operates independently of the utility, with batteries carrying the load overnight and through poor weather. Sized for autonomy rather than economy. Normally for sites with no reliable connection at all.
05Battery Storage
Worth It, or Not?
- What a battery is for
- Backup during outages, and shifting your own generation to the evening. It is a resilience decision more than a savings one.
- What it costs you
- Capital cost, space, ventilation, and replacement within the system's life. Batteries have a service life measured in cycles, shorter than the panels.
- Whether you need one
- If your supply is reliable and you are on net metering, a battery often will not pay for itself. We will say so.
06Installation
How a Home Installation Runs.
01
Site visit and roof survey
Usable area, shading through the day, structure and cable routes.
02
Consumption review
Twelve months of bills, your sanctioned load and how your use varies by season.
03
Proposal and sizing
A system size and configuration with the reasoning behind it, not just a number.
04
Application and approvals
Scheme application where applicable, and the distribution company's feasibility approval.
05
Installation
Mounting structure, modules, inverter, protection and earthing, to the applicable specifications.
06
Net meter and commissioning
The distribution company installs the net meter and inspects the installation before it is commissioned.
07Maintenance
Low Maintenance Is Not No Maintenance.
- Cleaning
- Dust reduces output. How often panels need washing depends on your location and the season — more in dry, dusty months.
- Visual checks
- Mounting hardware, cable condition, water ingress at penetrations, and anything that has started shading the array since installation.
- Monitoring output
- A gradual fall in generation that is not explained by weather or season is worth investigating early.
- Inverter life
- The inverter is the component most likely to need attention during the system's life. Keep its warranty terms to hand.
08Government Assistance
PM-Surya Ghar: Muft Bijli Yojana
Eligible residential consumers may qualify for central financial assistance towards a rooftop system, subject to the rules in force at the time of application.
The installation must be carried out by a vendor registered on the national portal, and the distribution company installs the net meter and physically inspects the system before assistance is processed.
Approval is decided by the authorities, not by Zenithra. We cannot promise that an application will succeed or that a particular amount will be received.
Central assistance — residential
| 1 kW₹30,000 per kW for the first 2 kW | ₹30,000 |
|---|---|
| 2 kW₹30,000 per kW for the first 2 kW | ₹60,000 |
| 3 kW and aboveA further ₹18,000 for the third kW; total capped at ₹78,000 | ₹78,000 |
Checked against official sources on 22 October 2026. Scheme rules may change — confirm current terms on the national portal before relying on these figures.
09Questions
What Homeowners Ask.
How much will I save?
We will not give you a savings figure before seeing your bills and your roof. What you save depends on how much the system generates at your location, how much of that you use yourself, your tariff and slab, the net-metering arrangement that applies to your connection, and how your consumption is spread across the day. Two identical systems on two houses can produce quite different bills.
What size system do I need?
Sizing follows from your consumption, your usable shadow-free roof area and your sanctioned load — in that order. It is common for roof area or sanctioned load to limit the system below what consumption alone would suggest. We look at twelve months of bills rather than a single month, because consumption varies by season.
Will solar work during a power cut?
A standard on-grid system shuts down during an outage. This is a safety requirement, so that the system cannot energise lines that line workers believe are dead. If you need power through outages, that means a hybrid system with battery storage, which costs more and adds a component that needs replacing within the system's life.
Am I eligible for the government subsidy?
Central financial assistance under PM-Surya Ghar: Muft Bijli Yojana is for eligible residential consumers, subject to the rules in force when you apply. Eligibility, the application route and the amounts are set by the scheme, not by us, and approval is decided by the authorities. We can explain the process and help you prepare, but we cannot promise approval or a specific amount.
How long does the whole process take?
The installation itself is usually the shortest part. Scheme application, distribution company feasibility approval, net meter installation and inspection are handled by other parties on their own timelines, and these vary. We will tell you what is in our control and what is not.
How long do the panels last?
Modules are typically supplied with long performance warranties and degrade slowly over their life. The inverter has a shorter service life and should be expected to need replacement at some point. Specific warranty terms depend on the products actually supplied — ask for them in writing before you commit.
10Consultation