Most guides on residential solar focus on independent houses. But millions of Indian homeowners live in apartments and housing societies. The process for going solar is possible for apartment residents, but it works differently and involves navigating your housing society alongside the DISCOM process. This guide covers both the individual flat approach and the collective society approach.

Two models for solar in apartments

Model 1: Individual flat with dedicated roof space

This works for ground floor or top floor flats with access to dedicated terrace or rooftop space that is not shared. The flat owner applies individually, gets their own net meter, and receives the subsidy directly.

This is the simplest model but applies to relatively few urban apartments in India, since most apartment buildings have shared terraces.

Model 2: Collective housing society project

This is the more common and often financially better model. The housing society (through the RWA) installs a common rooftop solar system and distributes the benefits across member flats.

There are two sub-models within this:
– A common system that powers common areas (lifts, corridor lighting, pumps), reducing the society’s common electricity bill.
– A larger system where individual flats receive proportional benefit through their own net metered connections.

PM Surya Ghar explicitly supports collective housing society applications, with each eligible flat owner claiming the subsidy for their proportional share.

Getting your RWA on board

The RWA or apartment owners’ association must approve any rooftop solar project, since the terrace is typically common property.

To build the case for your RWA, prepare a financial summary showing the cost, subsidy benefit, monthly savings on common area electricity bills, and net payback period for the society. Include specific quotes from 2 to 3 registered installers.

Common RWA objections and how to address them:

Roof warranty concerns: A quality installation by a registered installer uses mounting systems designed to preserve roof integrity with proper waterproofing. Ask the installer to provide a roof warranty alongside the system installation warranty.

Who owns the asset: The solar system is an asset of the housing society if funded collectively, and remains with the property if funded individually.

Structural load: Solar panels add approximately 12 to 15 kg per square metre of load. Most RCC rooftops are designed for significantly higher loads. Your installer should confirm structural suitability before installation.

The DISCOM and subsidy process for societies

For collective society applications:

The RWA applies through the PM Surya Ghar portal as the applicant entity. Each participating flat owner can claim the individual subsidy (up to Rs 78,000 per flat) for their proportional system share.

Net metering can be arranged at two levels: a single large net meter for the whole system on the society’s bulk connection, or individual net meters for each participating flat. The second option is administratively more complex but gives each flat owner direct control and individual net metering credits.

DISCOM practices on collective society applications vary. Some DISCOMs have simplified collective application processes; others treat each flat as an individual application. Check with your DISCOM’s solar desk early in the planning process.

Individual flat applications: what you need from your RWA

If you want to apply individually for your flat’s share of a rooftop system:

Get a no-objection certificate from your RWA confirming you have permission to install on the designated roof area.

Confirm in writing which portion of the terrace is designated for your use and that no other flat has a conflicting claim to the same space.

Your DISCOM may require the NOC as part of the feasibility application. Have it ready before you start the portal process.

State-wise apartment solar rules

Rules on apartment solar vary by state and DISCOM. Key variations:

Maharashtra (MSEDCL): MSEDCL allows collective society applications. Individual flat net metering requires each flat to have a separate net meter linked to their own consumer number.

Karnataka (BESCOM): BESCOM has processed collective society applications in Bengaluru. RWA NOC is standard requirement. Individual flat applications with dedicated roof area also processed.

Delhi (BSES / TPDDL): Individual and collective applications both possible. Shared terrace requires RWA NOC. Some older Delhi buildings have sanctioned load issues that limit system size.

Gujarat (MGVCL / DGVCL etc.): Gujarat DISCOMs have been active on housing society solar. GEDA has specific guidelines for collective applications.

Financial model for a housing society project

A typical example: a society with 20 participating flats installs a 20 kW common system.

System cost before subsidy: approximately Rs 9 to Rs 12 lakh.
Total central subsidy (20 flats at up to Rs 78,000 each): up to Rs 15.6 lakh potentially covering the full installation cost.

Note: Actual subsidy per flat depends on the proportional kW allocation per flat. A 20 kW system divided among 20 flats means 1 kW per flat, which attracts Rs 30,000 subsidy per flat, totalling Rs 6 lakh. System sizing and subsidy calculation should be planned carefully with a registered installer and verified with your DISCOM.

Monthly savings on common area electricity (lift, pumps, corridor lights) for a 20-unit society with a 20 kW system can be Rs 15,000 to Rs 25,000 per month.

Summing up

Solar for apartments and housing societies is entirely viable in India. The collective RWA model often delivers better economics due to scale pricing from installers and larger subsidy aggregation. The key steps are getting RWA consensus, selecting a registered installer with society project experience, and clarifying with your DISCOM whether collective net metering or individual metering is the preferred approach.