- Net metering nets export against import in kWh — you pay only for the net units.
- Net billing pays export a separate, usually lower rate; import is at full retail.
- Gross metering sells all generation at a fixed feed-in tariff; you buy power separately.
- The model is set by the state SERC and the system size — not chosen by the customer.
- Net metering rewards daytime self-use; gross metering does not. Verify the threshold with your SERC.
Net metering, net billing and gross metering all let a solar system feed the grid — but they pay for that power in very different ways. For an EPC, the model decides the customer's savings, the right system size, and the promise you can honestly make. This guide compares the three for Indian rooftop solar.
The short answer
Net metering is the most generous of the three: it subtracts your export from your import unit for unit, so each exported kWh is worth a full retail kWh. Net billing pays export a separate, usually lower rate. Gross metering sells everything at a fixed feed-in tariff while you buy all your power at retail. The state SERC decides which model applies, usually based on system size.
Net metering, explained
Net metering nets the units you export against the units you import, and you pay only for the net. A bidirectional meter records both directions. If you import 800 units and export 300, you pay for 500. Each exported unit cancels an imported unit at the same retail value.
Why EPCs and customers like it
Net metering gives the best payback because the export is valued at the retail rate. It rewards self-consumption during the day and uses the grid as a free "battery" across the billing cycle. For the full mechanics, see our net metering process guide.
Net billing, explained
Net billing splits the two flows. You pay full retail for every unit you import, and you are paid a separate rate — usually lower than retail — for every unit you export. There is no unit-for-unit cancellation.
Where net billing shows up
Many states now apply net billing above a size threshold, moving larger systems off net metering. Because export earns less than it costs to import, net billing makes self-consumption even more valuable: the best unit is the one the customer uses themselves. The threshold and the export rate vary by state — verify the current figure with your SERC.
Gross metering, explained
Gross metering treats generation and consumption as two separate transactions. All the solar a system generates is sold to the grid at a fixed feed-in tariff. Separately, the consumer buys all their power at the retail rate. The customer does not "use their own" solar at all.
When gross metering makes sense
Gross metering suits pure-export or investor models where the feed-in tariff is set high enough to be attractive on its own. For a typical rooftop where the customer wants to cut their own bill, gross metering is usually the least attractive of the three.
Side-by-side comparison
The table below sets the three models against each other on the points that matter to an EPC quote and design.
Comparison based on the Rights of Consumers Rules 2020 and common SERC practice. Rates and thresholds vary by state — verify the current figure with your SERC or DISCOM.
Which model your project actually gets
An EPC rarely chooses the metering model. The state SERC sets it, almost always by system size. A common pattern is net metering for small systems and net billing above a threshold, but the cut-off differs widely and changes with each amendment.
Find the rule before you quote
Because the threshold moves, you must check the live rule for the state and DISCOM before you promise savings. Some states watch a threshold — for example a size at which a system flips from net to gross — covered in our net-to-gross threshold guide. Verify the current cut-off with your SERC.
How the model changes your sizing
The metering model should shape your system design, not just your quote.
- Net metering — size for the year's consumption; export carries full retail value, so a slightly larger system is still efficient.
- Net billing — size around daytime self-use, because export earns less than import costs.
- Gross metering — size for the feed-in tariff economics, since self-use plays no part.
In every model, the plant size is capped by the customer's sanctioned load. Going above it needs a load enhancement. Build the right model into the quote from the start so the customer's savings are honest.
How state rules decide the model
Each State Electricity Regulatory Commission sets the metering models, the thresholds and the rates for its state, and each DISCOM applies them. A system that gets net metering in one state may get net billing across the border at the same size.
Always read the live state rule. Our state pages carry the DISCOM-specific model and limits — for example Rajasthan (JVVNL/AVVNL), Kerala (KSEB) and Maharashtra (MSEDCL). For C&I and HT projects, compare net metering against open access in our C&I net metering vs open access guide.
How SuryaHub helps you quote the right model
The metering model decides what a customer saves, so getting it wrong in a quote is a credibility risk. SuryaHub stores the model, threshold and export rate for each DISCOM and pulls them into the quotation automatically, so the savings you show match the real model. Net-metering steps then run inside government workflows. SuryaHub is pre-revenue; the only real pilots are Suryantra Energy and RGESPL, and the figures here are policy facts, not guarantees.
Quote the right metering model every time
See how SuryaHub applies each DISCOM's model in your quotes.
Related guides
Frequently asked questions
What is the difference between net metering and gross metering?+
Net metering subtracts the units a solar system exports from the units it imports and bills only the net. Gross metering sells all generation to the grid at a fixed feed-in tariff while the consumer buys all their power at the retail rate. Net metering rewards self-use; gross metering does not.
What is net billing?+
Net billing is a model where the units a solar system exports are paid a separate rate, usually lower than retail, while imported units are billed at the full retail rate. Net billing sits between net metering and gross metering, and many states now apply it above a size threshold. Verify the rate with your SERC.
Which metering model is best for a rooftop solar project?+
Net metering is usually best for a rooftop project because export is valued unit for unit, but the model is decided by the state SERC and the system size, not by choice. Smaller systems often get net metering; larger ones may fall under net billing or gross metering. Verify the current rule with your DISCOM.
Why are some states moving from net metering to net billing?+
Some states are moving larger systems from net metering to net billing because netting export unit for unit reduces DISCOM revenue. Net billing pays export a lower rate, which the DISCOM argues better reflects its costs. The size threshold for the switch varies by state and changes often, so verify the current figure with your SERC.
Does the metering model change how I size a system?+
Yes. Under net metering or net billing, you size the system around daytime self-consumption so the customer uses the most valuable units first. Under gross metering, self-use does not matter because all generation is sold. Always size to the sanctioned load and the state cap, and verify the limit with your DISCOM.
How does SuryaHub help with metering models?+
SuryaHub stores the metering model and rate for each DISCOM and applies it in quotes, so savings shown to a customer match the real model. SuryaHub is pre-revenue; the only real pilots are Suryantra Energy and RGESPL.
Sources & references
The definitions and model rules below come from primary government sources. Metering models, thresholds and rates are set by each state SERC, so always confirm the current rule with your SERC or DISCOM.
- Ministry of Power — Rights of Consumers Rules 2020 ↗
Defines net metering, net billing and gross metering nationally.
- Ministry of New & Renewable Energy (MNRE) ↗
Rooftop solar scheme guidelines and metering policy.
- Central / State Electricity Regulatory Commissions ↗
Each SERC sets the model thresholds and rates for its state.
Written by the SuryaHub team · reviewed against MoP, MNRE & SERC sources · updated 19 June 2026.
Method: Model definitions are taken from the government sources above and re-checked every 30 days. Thresholds and rates are state-set and change with each SERC amendment — verify with your SERC. SuryaHub is pre-revenue; only Suryantra Energy and RGESPL are real pilots.
Change log: 19 Jun 2026 — first published.