Net Metering, Gross Metering & Net Billing: Which One Applies to You
The metering model your DISCOM offers decides how much your solar exports are actually worth. The three models, in plain language.
Under net metering, you are billed on your net units — import minus export — at your normal retail tariff. Every unit you send to the grid offsets a unit you draw, rupee for rupee. It is the most favourable model for a rooftop owner and, for residential systems within a state capacity cap, still the most common.
Gross metering treats generation and consumption as two separate accounts. All your solar output is exported and paid at a fixed feed-in tariff, while everything you consume is billed at retail. When the feed-in rate is lower than the retail tariff — which it usually is — gross metering pays you less for the same array than net metering would.
Net billing is the hybrid many states are shifting to for larger and C&I systems: the electricity you self-consume offsets your bill at retail value, and only the surplus you export is paid at a lower feed-in or average-power-purchase-cost rate. It rewards sizing the system to your own daytime load rather than over-building for export.
Your payback math depends entirely on which model — and which capacity cap — your DISCOM applies, and these vary by state and change over time. Ask your DISCOM which model and limit apply to your connection before you size the system, and confirm the current rules rather than relying on a vendor’s summary.