Net Metering

What Is Net Metering?

Net metering is a regulatory and billing mechanism that allows rooftop solar consumers in India to send surplus electricity into the utility grid and receive a 1:1 kWh credit against the electricity they draw from the grid. The consumer is billed only for the net energy: total grid import minus total solar export, over each billing cycle.

In formal regulatory language used by State Electricity Regulatory Commissions (SERCs), net metering is defined as “an arrangement under which a consumer who is also a generator of electricity from a renewable energy source is connected to the distribution network of a Distribution Licensee, and the difference between the energy supplied by the licensee and the energy generated by the consumer is the chargeable quantity.”

In the solar industry, net metering is the single most important policy lever that makes rooftop solar economically viable for self-consumption. Without it, every unit of solar generated during peak production hours, when the building may not be using power, would be wasted. With net metering, that surplus becomes a stored credit on your electricity bill.

In the Indian context, net metering is regulated by individual SERCs under the framework provided by MNRE’s Grid Connected Rooftop Solar Programme. Each state maintains slightly different rules around capacity caps, settlement periods, and applicable consumer categories. The Central Electricity Authority (CEA) Connectivity Regulations 2019 set the broader technical interconnection standards that all net-metered systems must follow.

Key insight: Net metering effectively turns the DISCOM grid into a zero-cost, infinite-capacity battery. You “deposit” solar surplus during the day and “withdraw” grid power at night, paying only the difference.

Why Net Metering Matters

Net metering is the policy backbone of rooftop solar adoption in India. Its impact spans financial, technical, and strategic dimensions.

Financial Impact

• Shortens payback period by 3–5 years. Without net metering, a residential solar system would have to be perfectly sized to daytime consumption to be economical. With net metering, you can size to your full annual consumption and bank surplus credits.
• Eliminates the need for batteries in most residential installations. Batteries add ₹40,000–₹80,000 per kWh of storage capacity. Net metering replaces that with a near-zero-cost grid credit mechanism.
• Locks in protection against tariff hikes. Every export unit credited at today’s retail tariff becomes a hedge against future DISCOM rate increases, which have historically risen 3–5% annually.
• Enables system sizing based on roof area rather than instantaneous load matching. This maximises generation and long-term savings.

Technical Importance

• Allows oversizing up to sanctioned load, capturing more annual generation without wasting daytime surplus.
• Removes the engineering complexity of managing real-time surplus on-site through load shifting or storage.
• Simplifies inverter selection, standard grid-tied inverters suffice without requiring a hybrid inverter or storage-capable unit.

Business & Commercial Impact

• For C&I consumers, net metering makes a CAPEX rooftop solar project competitive with grid power on a per-unit basis.
• Reduces dependence on diesel gensets during daytime outages when paired with a hybrid inverter.
• Improves ESG and Scope 2 emissions reporting, exported solar units count toward renewable energy claims and carbon reduction targets.

Compliance Impact

• Net metering systems are mandatorily compliant with CEA Connectivity Regulations, IEC 61727, and IEEE 1547 for grid-interactive inverters, including anti-islanding protection in solar inverters.
• Establishes a legal, auditable record of green energy exported, important for Renewable Energy Certificates (RECs) in some configurations.

How Net Metering Works

Here is the end-to-end flow of how a kilowatt-hour generated on your roof becomes a credit on your bill:

1. Solar generation. Your rooftop PV array converts sunlight into DC electricity throughout the day.
2. DC to AC conversion. A grid-tied string inverter or microinverter converts DC to AC, synchronised to the grid’s voltage (230V / 400V) and frequency (50 Hz).
3. Priority self-consumption. The inverter feeds your home’s loads first. Any electricity you are actively consuming is supplied by solar before drawing from the grid.
4. Surplus export. When solar generation exceeds real-time consumption, the excess flows back through your service line into the DISCOM grid.
5. Bidirectional metering. The DISCOM-installed net meter records imported units (grid to you) and exported units (you to grid) in separate registers.
6. Monthly netting. At billing, the DISCOM subtracts your exported kWh from imported kWh.
   • If import > export: you pay for the difference at your normal retail tariff.
   • If export > import: the surplus is carried forward as a kWh credit to the next month.
7. Annual settlement. At the end of the financial year (typically 31 March), unused export credits are settled, either paid out at the state-notified Average Power Purchase Cost (APPC) or lapsed, depending on state policy.

The Net Metering Formula

Net Billable Energy (kWh) = Grid Import (kWh) − Solar Export (kWh)
Monthly Bill = Net Billable Energy × Retail Tariff (₹/kWh) + Fixed Charges + Taxes

Where:

• Grid Import = total energy drawn from DISCOM (recorded by import register)
• Solar Export = total energy fed into grid (recorded by export register)
• Retail Tariff = your applicable slab tariff (varies by consumer category and state)
• Fixed Charges = sanctioned-load-based charge that is not offset by solar export

Visual Explanation

Real-World Example

Residential, 5 kW System, Ahmedabad

A homeowner in Ahmedabad installs a 5 kW rooftop solar system with Heaven Green Energy under the PM Surya Ghar scheme.

• Annual generation: 7,500 kWh
• Annual household consumption: 9,000 kWh
• Annual grid import: 3,500 kWh
• Annual solar export: 2,000 kWh
• Net billable: 1,500 kWh
• Annual electricity cost: ~₹13,000 versus ₹78,000 before solar
• Payback: ~3.8 years with PM Surya Ghar subsidy

Commercial, 100 kW System, Surat Textile Showroom

• Annual generation: 150,000 kWh
• Annual consumption: 180,000 kWh (high daytime use)
• Solar offsets ~83% of total bill
• Payback: ~4.2 years with accelerated depreciation benefit

Industrial, 500 kW System, Vadodara Packaging Plant

Single-shift operation with heavy daytime load. Almost zero surplus export, direct self-consumption dominates. Net metering still useful for weekend and holiday surplus banking.

• Payback: ~3.5 years with AD + GST input credit

Institutional, 200 kW System, School in Gandhinagar

Generation during school hours is fully self-consumed. Vacation periods (summer, Diwali) generate large surplus that covers October through March consumption through net-metered credits.

Technical Specifications / Benchmarks

Benefits / Advantages

• Maximises ROI on rooftop solar by valuing every exported unit at the full retail rate.
• Eliminates need for batteries in most use cases, the grid acts as free storage.
• Hedges against future grid tariff hikes by locking in credit value at current retail rates.
• Allows oversizing up to sanctioned load for higher annual generation.
• Enables seasonal load balancing: banking surplus from summer for winter use.
• Reduces grid stress during daytime peak by injecting solar power locally.
• Simplifies bill accounting: one combined bill, no separate solar revenue tracking.
• Improves property value: net-metered solar systems are bankable, transferable assets.
• Supports India’s renewable energy targets without direct subsidy burden on DISCOMs.
• Enables PM Surya Ghar subsidy: net metering is mandatory for residential CFA claims.

Limitations / Drawbacks

• Capacity caps: Most states limit net metering to 500 kW–1 MW. Larger systems must use net billing or open access.
• Sanctioned load coupling: You cannot install more solar than your sanctioned load, a constraint for energy-hungry homes with undersized connections.
• No backup during outages: Standard grid-tied systems shut off during grid failure unless paired with hybrid inverter and battery.
• DISCOM resistance: Some DISCOMs delay application timelines because rooftop solar erodes their highest-paying customer base.
• Settlement risk: In some states, end-of-year surplus lapses instead of being paid out at APPC.
• Voltage rise issues in high-penetration zones may require additional inverter tuning or reactive power control.
• Annual settlement only: you cannot carry credits beyond the financial year in most states.
• Application fees and meter costs add ₹10,000–₹25,000 to project cost.
• Misconception alert: Many users assume net metering means “solar runs during power cuts.” It does not. That requires a hybrid system with battery backup.

Comparison Section

For most rooftop solar customers in India, net metering remains the most economically favourable option, which is why nearly all residential systems and most small C&I systems target it.

Applications

• Residential: Single-family homes, villas, apartments with common area solar. PM Surya Ghar subsidy makes this the fastest-growing segment.
• Commercial: Shops, offices, malls, hotels with daytime loads. Net metering offsets peak consumption.
• Industrial: Factories, warehouses, processing units. High self-consumption ratios maximise value.
• Institutional: Schools, colleges, hospitals, government buildings. Seasonal load patterns benefit from annual banking.
• Agricultural: Farmhouses, cold storage, dairy units. Component C of PM KUSUM uses net metering for solarised pumps.

Industry Standards & Regulations

Net-metered rooftop solar in India must comply with:

• MNRE Rooftop Solar Programme Phase-II Guidelines: sizing, eligibility, subsidy norms
• CEA Connectivity Regulations, 2019: technical interconnection standards
• CEA (Measures relating to Safety and Electric Supply) Regulations, 2010: safety requirements
• State SERC Net Metering Regulations: state-specific rules, caps, settlement periods
• IEC 61215 / IEC 61730: solar module certification
• IEC 62109: inverter safety standards
• IEC 61727 / IEEE 1547: grid interconnection and anti-islanding
• IS 16444: smart bidirectional meter standard
• ALMM: Approved List of Models and Manufacturers for modules
• BIS certification: all electrical components
• IS 732 / IS 3043: electrical installation and earthing

India-Specific Context

Net metering in India operates under a three-tier governance structure:

Central Framework (MNRE & CEA)

The Ministry of New and Renewable Energy (MNRE) issues the overarching Grid Connected Rooftop Solar Programme guidelines. The current Phase-II programme, extended under the PM Surya Ghar Muft Bijli Yojana, targets 40 GW of rooftop solar by FY 2027.

The Central Electricity Authority (CEA) sets technical interconnection norms under the CEA (Technical Standards for Connectivity of the Distributed Generation Resources) Regulations, 2013 and the CEA Connectivity Regulations, 2019.

State Regulations (SERCs)

Every state has its own Net Metering for Rooftop Solar PV Regulations, and the DISCOM net metering process varies state by state. Key state highlights as of 2026:

DISCOM Implementation

The actual rollout, application, feasibility study, meter installation, agreement signing, is done by your local DISCOM (UGVCL, MGVCL, DGVCL, PGVCL in Gujarat; BESCOM in Karnataka; MSEDCL in Maharashtra; TPDDL in Delhi). Most DISCOMs now have online portals: Gujarat’s Suryagujarat.guvnl.in, Karnataka’s Akshay Surya, and MNRE’s National Portal for Rooftop Solar.

Market Adoption

As of early 2026, India has crossed 15 GW of installed rooftop solar capacity, with PM Surya Ghar driving residential adoption. Gujarat alone accounts for over 3.2 GW of rooftop installations, most of them net-metered. Heaven Green Energy, Gujarat’s #1 ranked PM Suryaghar installer, has commissioned thousands of net-metered systems across all four Gujarat DISCOMs.

Future Trends

• Gradual shift to net billing for large consumers: The government has indicated that consumers above certain thresholds (varies by state, typically >10 kW or >500 kW) may transition to net billing while residential systems retain net metering.
• Smart meter integration: DISCOMs are rolling out AMI (Advanced Metering Infrastructure) that enables real-time net metering reconciliation, time-of-day export credits, and dynamic tariff adjustment.
• Virtual net metering: Some states are piloting arrangements where a solar plant at one location credits consumers at another location, enabling apartment dwellers and tenants to benefit.
• Battery-integrated net metering: As battery costs fall, hybrid systems with export optimisation will become common, allowing consumers to export during peak tariff hours rather than midday.
• Peer-to-peer energy trading: Blockchain-based platforms for direct solar trading between prosumers are in pilot stages in India, potentially disrupting traditional net metering over the next decade.

Common Mistakes & Misconceptions

1. Oversizing beyond sanctioned load. Application gets rejected; you have already bought the panels.

   • Avoid by: Verifying sanctioned load on your latest bill before sizing.

2. Using an unauthorised inverter. Inverters must be MNRE-listed and ALMM-compliant.

   • Avoid by: Working with an EPC that maintains an updated approved equipment list.

3. Submitting incomplete DISCOM application. Missing single-line diagram or technical data sheets causes weeks of delay.

   • Avoid by: Letting your EPC handle the entire DISCOM coordination.

4. Ignoring shading at design stage. A net-metered system that under-performs will erode ROI even if the meter works perfectly.

   • Avoid by: Running a proper shading analysis pre-installation.

5. Mismatching meter phase. A 3-phase consumer with a 1-phase inverter creates unbalanced export.

   • Avoid by: Matching inverter topology to your service connection.

6. Not understanding the settlement period. Customers who oversize hoping to “build credits” lose surplus at year-end in some states.

   • Avoid by: Sizing to ~95–105% of annual consumption, not 150%.

7. Filing wrong consumer category. Filing under domestic when actual use is commercial can void the agreement later.

8. Skipping load enhancement. If your sanctioned load is too low, enhance it before applying for solar.

9. Forgetting CEIG clearance. Many states require Electrical Inspector approval for systems >10 kW.

10. Assuming net metering = backup power. It is not. Outage backup requires a hybrid system with battery.

Key Takeaways

• Net metering is a billing arrangement where solar exports offset grid imports on a 1:1 kWh basis at retail tariff.
• It is the most economically favourable policy for rooftop solar self-consumers in India.
• Eligibility, caps (typically 500 kW–1 MW), and settlement rules are set by each state’s SERC.
• It requires a DISCOM-installed bidirectional meter and a grid-tied, anti-islanding-compliant inverter.
• A correctly sized net-metered system in India delivers payback in 3–5 years and ROI of 3–5× over 25 years.
• It does not provide backup during outages, for that, you need a hybrid battery system.
• Net metering is gradually being supplemented by net billing for larger consumers but remains the default for residential rooftop solar in 2026.
• Always verify sanctioned load, use ALMM-listed modules, and work with an MNRE-empanelled EPC for subsidy eligibility.
• Heaven Green Energy handles complete DISCOM coordination, net metering applications, and commissioning across all Gujarat DISCOMs.

Related Glossary Terms

• Gross Metering
• Feed-in Tariff (FiT)
• DISCOM
• PM Surya Ghar Muft Bijli Yojana
• Grid-Tied Inverter
• Anti-Islanding Protection
• Sanctioned Load
• Contract Demand
• Open Access Solar
• Banking in Electricity
• Renewable Energy Certificate (REC)
• PM KUSUM
• ALMM

Related Resources

• Residential Solar Services
• Commercial & Industrial Solar
• Turnkey Solar EPC
• DREBP & PM-KUSUM
• Solar Calculator, Estimate Your Savings
• Complete Guide to Solar Installation in Gujarat
• Net Metering in India
• PM Surya Ghar Complete Guide
• OPEX vs CAPEX Solar
• Solar Payback Period
• How to Choose a Solar Contractor

Sources & References

• MNRE Grid Connected Rooftop Solar Programme Phase-II Guidelines
• CEA Connectivity Regulations, 2019
• GERC Net Metering Regulations
• MERC Net Metering and Net Billing Regulations
• KERC Solar Rooftop Regulations
• TNERC Net Metering Regulations
• DERC Net Metering Regulations
• UPERC Net Metering Regulations
• RERC Net Metering Regulations
• IEEE 1547 / IEC 61727 Grid Interconnection Standards
• IEC 62116 Anti-Islanding Standard
• IS 16444 Smart Meter Standard
• IS 13779 AC Static Watthour Meters