A commercial rooftop proposal can look attractive because its annual generation is high. The harder question is what happens to electricity the business does not use when it is generated. Net metering, net billing and gross metering put that surplus into different accounts. The arrangement allowed for a given consumer and state can change both export value and the practical size of the plant.
Direct answer. Net metering offsets eligible imports with exported units under a defined settlement rule. Net billing first serves the site’s load and credits surplus exports at the approved purchase rate under the amended Maharashtra and published Gujarat frameworks. Gross metering accounts for all generation separately. Check the current amendment, effective date, account and export limit before comparing the routes.
What do net metering, net billing and gross metering mean?
Under net metering, a bidirectional meter records electricity imported from the grid and exported to it. The regulator specifies how those quantities are set off within a billing period and what happens to any remaining credit. A daytime self-consumed solar unit never crosses the revenue meter as an export. It reduces the import that would otherwise occur at that hour. The net-metering glossary gives the basic meter vocabulary.
Net billing must use the regulator’s amended definition. Maharashtra’s 2023 First Amendment replaces Regulation 2.1(n): surplus energy injected into the grid is purchased by the licensee, while grid imports are billed at the approved retail tariff after the purchase credit. New Regulation 11(A) states that generation is first used for self-consumption. Selling the entire output is the separate gross-metering concept.
Gross metering accounts for total plant generation for sale and grid consumption separately. MP’s 2024 rooftop regulation provides that route; Maharashtra’s 2023 amendment and Gujarat’s published 2026 DRES regulation also distinguish gross metering. Each has its own capacity, tariff and approval conditions.
Before valuing exports, confirm the approved arrangement, the set-off period, the treatment of excess units and the charges on remaining imports. Only after answering those should an EPC turn annual generation into a bill forecast. The feed-in tariff glossary explains why a purchase rate can differ from the retail import tariff.
| Arrangement | Solar account | Grid account | First business question |
|---|---|---|---|
| Net metering | Exports offset eligible imports under the regulation | Remaining net import billed under tariff | What is the set-off period and treatment of surplus? |
| Maharashtra-style net billing | Entire generation sold under the agreement | Consumption billed at retail, purchase credited | What is the agreed purchase tariff? |
| MP-style gross metering | Entire generation purchased under the regulation | Total consumption billed at retail, purchase credited | Does the category and capacity qualify? |
These definitions explain the mechanisms, not their profitability. A factory with steady daytime load often values self-consumption differently from a plant that exports much of its output. The next step is to read the state rule and the licensee’s approved offer.
How does Gujarat’s published settlement framework work?
Gujarat rule update, 30 October 2026. GERC has published DRES Regulations, Notification 11 of 2026, signed on 30 October 2026. Clause 1.2 makes commencement depend on notification in the Official Gazette. Confirm that commencement and the rules applicable to this application with the DISCOM before committing to a size or export value. Do not assume an existing agreement has automatically changed. The 2022 Third Amendment had already replaced the older 50% capacity screen and the 2020 settlement clauses.
The published 2026 DRES regulation, clause 9.1.5, allows non-residential net-metering export set-off only up to 30% of grid imports in the billing cycle, with applicable banking charges; exports beyond that limit lapse. Residential consumers have full billing-cycle set-off without banking charges, and remaining surplus is purchased at ₹2.25/kWh or a later rate specified by GERC. Clause 9.1.7 limits off-peak exports to off-peak imports, while peak exports can offset either slot. Verify commencement and the account’s applicable agreement before using these terms.
Published net billing under clause 9.2 first uses generation for self-consumption, then applies the specified purchase formula to exported energy. Gross metering separately accounts for all generation. Check the complete clause, account terms and effective date before selecting a mechanism.
For an older installation, obtain the approved agreement, commissioning date and applicable regulation. The 2022 Third Amendment had already replaced the 2020 Regulation 9 provisions, so a new model should not rely on a 2020 manufacturing-MSME ratio alone.
How does Maharashtra distinguish the arrangements?
The 2023 MERC First Amendment limits net metering to the lower of 5 MW and contract demand/sanctioned load. For other arrangements, contract demand/sanctioned load remains the stated capacity ceiling. Use the 2019 principal regulation with this amendment and the 2024 Second Amendment.
For net metering, eligible excess credits carry under Regulation 11 and remaining credits are settled at the financial-year boundary under the applicable purchase rule. ToD consumers must follow the relevant slot accounting. Fixed, demand and other applicable charges remain separate.
For net billing, amended Regulation 2.1(n) and inserted Regulation 11(A) first allocate generation to self-consumption. The grid bill then charges imported units at the retail tariff and credits exported surplus at the approved purchase tariff. It does not require all generated energy to be sold. Gross metering is the separate total-generation arrangement.
Illustrative energy balance: a site uses 1,000 kWh and generates 600 kWh in a period, of which 400 kWh is consumed directly. It imports 600 kWh and exports 200 kWh. Under the amended net-billing model, the energy calculation charges the 600 imported units and credits the 200 exported units at their respective rates. The 400 directly used units are not sold. Rates, dates, other charges and actual interval settlement must be added for a real bill.
What does MP allow for net and gross rooftop arrangements?
The MPERC RG-39(II) regulation notified 14 March 2024 covers net metering, gross metering, group net metering and virtual net metering. Eligible consumers in all categories may use net metering up to 500 kW, subject to the regulation’s load or contract-demand cap and other conditions. Gross metering is permitted up to 1 MW under its own conditions. Existing qualifying net-metered plants above the new 500 kW limit have a transitional provision. These are distinct routes, not two names for the same bill.
Net metering offsets eligible imports with the rooftop system’s export under the regulation’s billing-period accounting. Gross metering purchases total generated energy at the specified discovered tariff mechanism while the consumer pays the retail supply tariff for its total grid consumption, with a credit for the purchased generation. A business should ask the DISCOM to show which meter arrangement it has approved and how the credit appears on the bill. The gross route does not allow a buyer to count self-consumption of the same solar unit as a second benefit.
The MPERC first amendment notified 18 June 2026 changes application-process provisions. It should be read with the 2024 regulation rather than assumed to replace its category and settlement structure. The MPERC FY 2026-27 retail tariff order dated 26 March 2026 expressly sends net, group, gross and virtual settlement back to that rooftop regulation as amended. This is a useful cross-check when a proposal quotes only the retail tariff.
A hypothetical MP factory with a strong daytime load may prefer to test net metering first because direct use of solar can offset its own imports. A business with a different ownership or sale objective may examine gross metering. That is a decision framework, not a recommendation for every site. The approved consumer category, capacity and network conditions determine whether either route is available. The industrial solar installation guide covers the broader HT design work.
MP’s regulation also restricts combining certain rooftop arrangements with open access on the same qualifying consumer route. If a factory already uses open access, the EPC should review that restriction before proposing a rooftop net-metered plant. The open-access glossary explains the separate off-site procurement mechanism. A sales model that assumes both benefits without regulatory approval is not ready for signature.
- ✓ Regulation and consumer category are documented.
- ✗ Export is valued at retail without checking the route.
How do the three states compare for a commercial buyer?
The table below captures the route, not a universal export tariff. Rates can be fixed by a commissioning document, generic tariff, discovered tariff or later regulator order. A business should not use a rupee figure from an older article as if it applied to every new plant. The named sources are current regulatory starting points as reviewed on 30 October 2026.
| State and official source | Business rooftop options described | Export and settlement question |
|---|---|---|
| Gujarat, 2026 DRES publication | Net metering, net billing, gross, group and virtual arrangements | Confirm Gazette commencement, non-residential export-setoff limit, banking and account terms |
| Maharashtra, 2023 amendment with 2024 amendment | Net metering up to lower of 5 MW and approved demand/load; surplus-based net billing | Separate directly used, imported and exported energy |
| Madhya Pradesh, 2024 regulation with June 2026 amendment | Net metering up to 500 kW; gross metering up to 1 MW | Own load, category, purchase tariff and approved arrangement |
The 2023 MERC amendment is essential when reading the 2019 definitions. It changes net billing to a surplus-injection mechanism and adds a separate gross-metering route. A comparison based only on the original 2019 wording would misstate the customer’s bill.
This table does not imply that every new business can choose freely between all mechanisms. Technical feasibility, sanctioned load, plant size, premises rights and open-access status can narrow the choice. The net-metering in India guide provides the broad background, while this article addresses the business category and export decision that home-focused guides often leave unresolved.
Verdict. Compare the annual value of self-consumed and exported units under the arrangement actually available to the site. The name of the meter is less important than the written set-off, purchase and settlement terms.
How does export value change the right rooftop size?
Every extra kilowatt of rooftop capacity adds generation at particular hours, not evenly across the day. When that output is consumed behind the meter, it may avoid retail energy imports. Once it exceeds the business’s load, the additional output follows the approved export settlement. If that route has a different value, the marginal benefit of later panels can differ from the first panels. Roof area is therefore a physical upper bound, not a financial sizing target.
Imagine a hypothetical office that uses 70 kW at noon on weekdays and 10 kW on holidays. A 60 kW plant may be mostly self-consumed on weekdays but export more on holidays. A 100 kW plant adds substantial weekday midday exports as well. The actual monthly balance depends on solar output, operating hours and meter rules. The numbers are a teaching profile, not a case study or yield forecast. An EPC should show annual self-consumed, imported and exported units for each candidate size.
Across the three states, the model must separate direct use, import, export and any credited energy. Use Gujarat’s applicable instrument and commencement date, Maharashtra’s amended surplus-net-billing definition, or MP’s selected net/gross mechanism. Do not price every generated unit at the retail rate. The solar ROI guide explains the broader calculation.
The checklist should be repeated for a smaller, middle and larger plant. For each, estimate monthly generation, hourly self-consumption, export and remaining grid import. Apply the current purchase or credit rule to export, and retain fixed, demand, PF or kVAh lines that remain. The preferred size may be the point where extra generation begins to earn much less, or it may be limited first by roof, load or network approval. There is no universal percentage at which to stop.
Mid-article action
Take twelve bills, daytime load data and the approved tariff category to the commercial solar proposal page. Ask for an export-aware model of at least two plant sizes.
How Heaven Green Energy helps check Settlement
The proposal should name the state regulation, amendment and exact clause for the chosen arrangement. It should identify the consumer category, renewable-attribute treatment, sanctioned load or contract demand, and any open-access arrangement already on the meter. The single-line diagram should show the revenue meter, generation meter and proposed interconnection. The financial sheet should separate self-consumption, imports, exports, purchase credits and other bill components.
Ask for treatment at each billing-cycle and financial-year boundary. For Gujarat, confirm the applicable regulation, commencement and any export-setoff cap. For Maharashtra, distinguish net-metered credits, surplus-based net billing and gross metering. For MP, obtain the selected mechanism and its purchase tariff in writing.
- Confirm the licensee, tariff code and rooftop regulatory route.
- Check system-size limits against sanctioned load or contract demand.
- Ask for a month-by-month import, self-consumption and export table.
- Read the settlement period and purchase-rate clause in writing.
- Keep demand, fixed, PF or kVAh and tax lines separate.
- Compare at least two feasible plant sizes on the same assumptions.
The commercial solar page is the proposal route for most business premises. The industrial solar page is relevant for factory connections and larger electrical interfaces. A reader can send the bills, meter data and roof plan, then ask Heaven Green Energy to use the same documented route test as any competing EPC. The company should not be evaluated on a claim that every generated unit has retail value.
- Regulation clause and tariff code
- Approved meter scheme
- Monthly export forecast
- Settlement and purchase terms
- Every export priced at retail
- MSME status assumed
- Open access ignored
- One annual number replacing the bill model
The service routes for a site-specific review are:
- Commercial solar for a business bill and rooftop proposal.
- Industrial solar for a larger factory connection and protection review.
How can a business verify the first solar bill?
Keep the approved application, meter-test report and signed agreement beside the first three bills. Confirm that the bill names the expected arrangement and that the import and export registers match the installed meter. Compare the opening and closing readings, billing dates and any carried credit. If the plant is in a monthly set-off category, reconcile that month before assuming the next month’s credit. If it is in a financial-year settlement route, track the balance through the year.
For a Gujarat business, first establish which regulation and agreement apply to the commissioning date and any later revision. Obtain interval import/export records and the applicable banking or surplus-purchase clause. The 2020 manufacturing-MSME ratio is not a current substitute for that evidence.
For a Maharashtra net-metered business, compare monthly credited units with the MERC 2019 rooftop regulation and watch the financial-year settlement. For a Maharashtra net-billing business, look for the generation purchase credit and the retail grid bill as separate streams. A mismatch can arise if the generation meter and consumer meter cover different dates, so note both reading periods before raising a dispute.
For an MP gross-metered business, the generation purchase and retail consumption should be visible as distinct accounts under the MPERC 2024 regulation. A net-metered MP business should instead see the regulation’s offset and carried-credit treatment. The MPERC FY 2026-27 tariff order dated 26 March 2026 directs these settlements back to the rooftop regulation. Do not resolve a difference by applying a generic retail unit rate to every exported kWh.
Finally, check charges that remain: fixed or demand amounts, PF or kVAh treatment, taxes and any meter-related line. The first bill may cover an unusual number of days after commissioning, so normalize comparisons by dates and production. Save the reconciliation and ask the EPC to explain any variance between its proposal and the actual approved meter arrangement.
Frequently asked questions
Does Gujarat permit business rooftop arrangements?
The published framework provides routes for commercial and industrial consumers. GERC’s DRES instrument signed 30 October 2026 includes net, net-billing, gross, group and virtual arrangements; Gazette commencement and account applicability require confirmation.
Is Maharashtra net billing the sale of all solar generation?
Under the 2023 amendment, no. Generation is first used for self-consumption and exported surplus is purchased at the approved rate, while imports are billed at retail. Gross metering accounts for total generation separately.
What is Maharashtra’s net-metering capacity limit?
The 2023 amendment sets the lower of 5 MW and the consumer’s contract demand/sanctioned load, subject to other applicable conditions.
Can an MP business use gross metering?
The 2024 regulation permits eligible consumers in all categories up to 1 MW under its gross-metering conditions. Check the actual load, selected mechanism, tariff and DISCOM approval.
Can unused credits carry indefinitely?
No general rule allows that. Settlement periods, caps, lapse and purchase provisions depend on the state, applicable regulation and account agreement. Ask for a worked bill using the correct period.
Will the whole bill disappear after solar?
Fixed, demand, duty and other applicable charges may remain. Power factor, kVAh and ToD require their own model. Compare individual bill components rather than using one blended price for every generated unit.