Community solar is a way for a home without a suitable roof to buy a share of a solar plant built elsewhere, and to have its share of the output credited on the subscriber's bill. The people who sign up are called subscribers. It exists because many homes cannot have panels: they may be flats, rented homes or shaded roofs.
Here is how it works. A company builds a solar plant on land away from the homes. It divides the output of the plant into shares. A home signs up as a subscriber and gets a share. Each month the plant produces power and sends it to the grid. The electricity company works out how much power belongs to each subscriber's share and credits it on that subscriber's bill. The subscriber then pays the solar company a fee for the share, which is usually a little less than what the electricity company would have charged for the same power.
In India, the credit is given through virtual net metering. In ordinary net metering, a home's own panels send power to its own meter. In virtual net metering, the plant has one meter, and the discom divides the units it records among several consumers, each of whom gets credit on their own bill. Each state's electricity regulator decides whether virtual net metering is allowed, who may use it and on what terms. For example, Delhi's regulator has allowed it since 2019, and Maharashtra's regulator allowed it in 2024 for residents of apartment buildings. The model began in the United States, and the two companies listed here work mainly there.
Consider a household in a rented flat in Surat that signs up for a 2 kilowatt share. In a sunny month, the share produces 250 units of electricity, and the discom takes ₹1,500 off the bill. The subscriber pays the solar company ₹1,350 for the share. The saving is ₹150 a month. (These figures are only illustrations.)
The company needs the subscriber's bill data, which it reads through a utility data API where one is available. It bills each subscriber monthly with subscription billing software. The plant is built from solar panels on leased land, managed with tools similar to land management software for oil and gas. Community solar is a way to share the benefits of rooftop solar with homes that have no roof of their own.