How Community Solar Lets Apartments Share Savings

Rooftop solar has usually needed something most apartment residents don’t have: full control of a roof. In most buildings, the terrace is common property, shared by the whole society and owned by no single flat. That’s kept solar out of reach for many city apartments, even ones with a perfectly good rooftop.

Community solar through Virtual Net Metering (VNM) removes that barrier. Any consumer may install a plant on a suitable rooftop or open area and share the benefits among all participating connections within the same DISCOM area of supply.

How It Works

The society installs one solar plant on the common rooftop. All the power it generates is exported straight to the grid through a single dedicated renewable energy meter— it isn’t wired into anyone’s flat directly so your credit has nothing to do with where your flat sits in the building Each month, the DISCOM totals the units exported and splits them among participating flats, based on the share each one agreed to when they signed up.

Say your flat holds a 2 percent share. If the plant exports 6,000 units in a month, you’re credited 120 units. On your bill, that credit is subtracted from what you actually drew from the grid, so a flat that used 300 units and earned a 120-unit credit pays for only 180. Any month you generate more than you use, the extra rolls over to the next bill. Shares aren’t fixed forever, either — Delhi lets participants revise them once a year with advance notice to the DISCOM, so the system can adjust as flats change hands or usage changes.

Who Can Use VNM

Each state has slightly different regulations. In Delhi, the DERC (Delhi Electricity Regulatory Commission) guidelines apply to all consumers in the National Capital Territory, including those with a single point of supply, such as buildings or societies billed through one collective connection instead of separate meters for each flat. To keep VNM operational, several requirements must be met:

• The plant and every participating connection sit within the same DISCOM’s area of supply.
• Everyone has signed a formal agreement spelling out their share
• All generation flows through one dedicated meter at the plant

A Real Example: One installation, multiple beneficiaries

Mayur Vihar CGHS

One cooperative group housing society was paying close to ₹75,000 a month for common-area power, which would go up to about 800 units a month. After installing a 60-kW rooftop plant, the 4,000 units it generates each month now cover the lifts, pumps, and lighting directly, bringing the consumption charges down to nothing. The remaining 3,200 units are split evenly across 32 flats, about 100 units each, saving each household roughly ₹800 a month. Across the society, that adds up to more than ₹8.5 lakh a year in 2026.

Why It Matters for Residents

VNM saves money in two places at once. It first cuts what residents pay through their maintenance for shared spaces like lifts, water pumps and corridor lighting. It then lowers each flat’s own electricity bill through the automatic monthly credit, with no rewiring or action needed from residents. And because the credit is measured in units, not rupees, it holds its value even as tariffs rise year after year.

Things to Check Before You Start

A few things are worth confirming early, not after the paperwork is already moving:

• DISCOM technical feasibility approval takes time. Build it into your timeline rather than treating it as a formality.
• Getting 30, 60, or 100 flats to agree on cost-sharing and share ratios usually takes longer than the DISCOM application itself. Settle this within the society first.
• Not every state has an operational VNM framework[KP4]. Confirm your DISCOM actually processes VNM credits before you plan around it.
• Most residents simply don’t know this option exists. A short awareness session with your Residential Welfare Association can save months of back-and-forth later. 

In Short

The terrace was never really a private asset — it’s a common property that no single flat could put to use on its own. VNM is what turns it into a shared one: a single plant, split fairly, lowering bills for every flat in the building, not just the one closest to the sun.