If you're planning a solar installation in Tamil Nadu — residential, commercial, or industrial — TANGEDCO's policies govern how your system connects to the grid, what you're paid for the electricity you export, and how your bills are calculated. The regulations have evolved significantly over the past two years. This guide covers the current framework as of 2026, including net metering procedures, feed-in tariffs, recent regulatory changes, and how to handle common approvals delays.

TANGEDCO's Net Metering Policy: The Core Framework

Tamil Nadu's net metering framework is governed by the Tamil Nadu Electricity Regulatory Commission (TNERC) Net Metering Regulations, which TANGEDCO implements as the state distribution licensee. The current regulations permit eligible consumers to:

Install rooftop solar systems and connect them to the TANGEDCO distribution network
Offset their electricity consumption with self-generated solar power
Export surplus generation to the grid and receive credit against future consumption
Settle excess export credits annually

Net metering in Tamil Nadu operates on a monthly netting basis — at the end of each billing cycle, your import units and export units are offset. If you import more than you export, you pay the net difference at your standard TANGEDCO tariff. If you export more than you import, the excess export is carried forward as a credit to the next month. Annual settlement of remaining credit is made at the avoided cost rate (the utility's cost of procuring power), which is significantly lower than retail tariff.

Eligible System Sizes

Consumer Category	Maximum Eligible Capacity
LT Residential (LT2A, LT2B)	1 kWp to sanctioned contract demand (max 10 kWp typical residential)
LT Commercial (LT3)	Up to 1,000 kWp (1 MWp)
LT Industrial (LT4/LT5)	Up to 1,000 kWp (1 MWp)
HT consumers (HT1, HT2, HT3)	Up to 2,000 kWp (2 MWp) via separate HT net metering process

Capacity limit rule: The solar system capacity cannot exceed the consumer's sanctioned load (contract demand). For a home with a 5 kW sanctioned load, the maximum net metering eligible capacity is 5 kWp. Oversized systems are not approved.

Net Metering vs Gross Metering

Understanding the distinction is critical for financial planning:

Net Metering (current standard for LT consumers):

Your solar generation first offsets your own consumption
Only the net surplus (after self-consumption) is exported to the grid
You are billed only for net imports
Most financially favourable arrangement for self-consumers

Gross Metering:

All solar generation is exported to the grid at a feed-in tariff
You pay for all your consumption at retail rate
Only suitable when export tariffs are significantly higher than retail (currently not the case in Tamil Nadu)

TANGEDCO's current policy for LT consumers defaults to net metering. HT consumers above certain thresholds may be offered gross metering or power purchase agreement (PPA) structures.

Current Feed-In Tariff Rates (2026)

TNERC determines feed-in tariffs for solar prosumers through periodic orders. Current applicable rates for annual settlement of excess export credits:

Consumer Category	Avoided Cost / Settlement Rate
LT Residential	₹2.25–₹2.75 per kWh
LT Commercial	₹2.50–₹3.00 per kWh
LT/HT Industrial	₹2.75–₹3.50 per kWh

These rates reflect TANGEDCO's avoided cost of power purchase — the rate at which the utility buys power from the open market or generators. They are notably lower than the retail tariff consumers pay (₹4.50–₹8.00+ per unit depending on slab), which is why maximising self-consumption (using your own solar power before exporting) gives you the best financial return.

Key insight: Every unit you self-consume is worth your full retail tariff (₹4.50–₹8.00/unit). Every unit you export is worth only the settlement rate (₹2.25–₹3.50/unit). Design your system and consumption patterns to maximise self-consumption.

TANGEDCO Solar PPA Tariff 2026

For large commercial and industrial consumers — particularly HT (High Tension) consumers with high contracted demand — TANGEDCO also facilitates solar energy procurement through Power Purchase Agreements (PPAs) as an alternative to conventional net metering.

What Is a Solar PPA in the TANGEDCO Context?

Under a solar PPA, a third-party solar developer installs and owns the solar generation system (either on your premises or at a remote site). You agree to purchase the solar power generated at a pre-agreed PPA tariff rate for the contract duration, typically 15–25 years. Capital outlay is zero — the developer recovers their investment through the energy payments over the contract period.

TANGEDCO's role is as the distribution licensee that facilitates the open access framework through which the solar power is wheeled to your facility, or as the offtaker in utility-scale solar PPAs for its own procurement.

TANGEDCO Solar PPA Tariff Rates 2026

TNERC determines benchmark solar tariffs through periodic tariff orders. Applicable rates for FY 2025–26:

Procurement / Consumer Category	PPA Tariff Rate
TANGEDCO utility-scale procurement (>1 MW)	₹2.60–₹2.90 per kWh
Group captive solar projects (HT industrial)	₹2.80–₹3.20 per kWh
Third-party open access (HT consumers)	₹3.00–₹3.50 per kWh

These PPA rates are significantly lower than the HT industrial retail tariff of ₹6.50–₹8.00/kWh, delivering typical bill savings of 40–60% for large consumers.

Additional charges apply to open access solar PPA arrangements: wheeling charges, cross-subsidy surcharge (CSS), and transmission charges. Net savings after these charges typically range from 25–45% depending on the consumer category and voltage level.

Solar PPA vs Net Metering: Which Is Right for You?

Factor	Net Metering	Solar PPA
System ownership	Consumer owns	Developer owns
Upfront capital	Yes (with subsidy for residential)	Zero capex
Applicable to	LT consumers up to 1 MWp	HT industrial & large commercial
Savings potential	Up to 90% bill reduction	25–45% after open access charges
PM Surya Ghar subsidy	Eligible (residential LT)	Not applicable
Contract lock-in	None	15–25 year PPA
Who manages TANGEDCO approvals	Consumer / Installer	Developer handles

For most residential and small commercial LT consumers in Tamil Nadu, net metering with system ownership delivers a better long-term return on investment — typically 4–5 year payback and free energy for 20+ years. Solar PPAs are primarily suited to large HT industrial consumers (factories, data centres, large hospitals, textile mills) where capital constraints or accounting preferences make a zero-capex structure attractive despite lower long-term savings.

Bidirectional Meter Installation

When your net metering application is approved, TANGEDCO replaces your existing single-direction meter with a bidirectional (net) meter. This meter independently records:

R1 register: Units imported from TANGEDCO grid
R2 register: Units exported to TANGEDCO grid

The difference (R1 minus R2) determines your net consumption for billing. If R2 exceeds R1 in a month, the excess export credit is rolled forward. Always photograph your meter registers monthly to maintain your own records — this protects you in case of a meter reading dispute.

Meter type: TANGEDCO installs Secure or L&T make smart meters in most recent net metering connections. Older installations may have conventional bidirectional meters. Smart meters transmit readings automatically and reduce estimated billing errors.

Application Procedure: Form NM and the Approval Process

Step 1: Submit Form NM Online

Access the net metering application (Form NM) through the TANGEDCO website (tneb.in → Solar → Net Metering). Required details:

Consumer number and category
Proposed system capacity (kWp)
Inverter make and capacity
Panel make, model, and total count
Single-line diagram (signed by a licensed electrical supervisor or contractor)

Step 2: Technical Scrutiny

TANGEDCO's EE (Electrical Engineer) or AE (Assistant Engineer) at your area distribution office reviews the application for:

Compliance with maximum capacity limits
Equipment specifications (inverter and panel standards)
Single-line diagram correctness
Anti-islanding and protection relay compliance

Step 3: Technical Sanction Letter

On approval, TANGEDCO issues a Technical Sanction Letter authorising the installation. You can now proceed with system installation. Do not begin installation before receiving technical sanction — post-hoc approvals are not guaranteed and may delay net meter installation by months.

Step 4: Installation and Inspection

After installation is complete:

Notify TANGEDCO and request a site inspection
A Junior Engineer (JE) visits to verify the installation matches the approved design
The JE checks earthing, anti-islanding settings, panel labelling, and cable management

Step 5: Agreement Execution and Meter Installation

Upon satisfactory inspection:

Sign the Net Metering Agreement with TANGEDCO
Pay the applicable metering charges (bidirectional meter deposit, typically ₹3,000–₹8,000 depending on consumer category)
TANGEDCO schedules and installs the bidirectional meter

TANGEDCO Charges Summary

Charge	Typical Amount
Application processing fee	₹500–₹2,000 (category dependent)
Bidirectional meter security deposit	₹3,000–₹8,000
Inspection charge	Nil to ₹500

Timeline for TANGEDCO Approvals

Realistic timelines based on current processing speeds:

Stage	Typical Duration
Form NM submission to Technical Sanction	15–45 days
Technical Sanction to installation	As per your schedule
Installation to inspection	7–21 days
Inspection to net meter installation	15–45 days
Total end-to-end	45–120 days

Approval timelines vary significantly by zone. Coimbatore and Chennai zones have generally faster processing than smaller district headquarters. Applications that are incomplete or have minor discrepancies in the single-line diagram are routinely returned for correction, adding weeks to the process.

Handling Delays and Escalation

If your application has been pending beyond the standard timeline:

First step: Contact the section office JE or AE with your application reference number for a status update
If no response within 7 days: Submit a written escalation to the Divisional Engineer (DE) at the area office
Formal grievance: File through the TANGEDCO online grievance portal (tneb.in → Consumer Services → Grievance) for a trackable complaint reference
TNERC grievance: If TANGEDCO does not resolve within the regulatory timeline, lodge a complaint with TNERC's Consumer Grievance Redressal Forum (CGRF) — contact details below

Important: TNERC regulations specify that TANGEDCO must process net metering applications within 30 days of receiving a complete application. Delays beyond this are a regulatory violation and CGRF complaints are effective.

Banking of Energy: Annual Settlement Policy

Tamil Nadu follows an annual energy banking model:

Monthly import/export netting happens every billing cycle
Cumulative excess export credits at year-end are settled at the avoided cost rate (₹2.25–₹3.50/unit)
The banking year runs April 1 to March 31
Remaining credit at end of banking year is paid out — no carry-forward beyond one year

This makes system sizing important. Significantly oversizing your system leads to large annual settlements at the low avoided cost rate, reducing your effective return. The optimal strategy is to size your system to offset approximately 85–95% of your annual consumption through self-consumption and net metering, with minimal annual surplus.

Recent Regulatory Changes and Updates (2026)

Renewable Purchase Obligation (RPO) Targets

TNERC has increased RPO targets for HT consumers, requiring a specified percentage of consumption to come from renewable sources. This has accelerated solar adoption among large industrial consumers in Tamil Nadu's manufacturing belt — Tirupur, Coimbatore, and SIPCOT zones — who are now mandated to procure renewable energy.

Prosumer Regulation Framework

TNERC's updated prosumer regulations (2025–26) formalise the rights and obligations of solar prosumers, including:

Right to access energy generation and export data
Obligation to maintain inverter anti-islanding certification
Conditions for grid disconnection and reconnection
Provisions for aggregated net metering for apartment complexes (RWAs) — a growing segment in Chennai and Coimbatore

Smart Meter Rollout

TANGEDCO's ongoing smart meter deployment program is progressively replacing conventional meters across Tamil Nadu. Smart meters automatically transmit bidirectional readings, reducing estimated billing and eliminating meter reading disputes for net metering consumers.

TANGEDCO Zone-Wise Contact Details for Solar / Net Metering

Chennai Zone (South): TANGEDCO Chief Engineer (Distribution) — Southern Region, Anna Salai, Chennai — 600 002 Helpline: 1912 | tneb.in

Coimbatore Zone: TANGEDCO Superintending Engineer (O&M), Coimbatore Circle, Race Course Road, Coimbatore — 641 018 Local section offices handle Form NM submissions

Madurai Zone: TANGEDCO Superintending Engineer (O&M), Madurai Circle, Madurai — 625 020

TNERC Consumer Grievance Redressal Forum (CGRF): TNERC, No. 19A, Rukmini Lakshmipathi Road, Egmore, Chennai — 600 008 Website: tnerc.gov.in | For escalating unresolved TANGEDCO complaints

Tristar Green Energy Solutions in Coimbatore has completed TANGEDCO net metering approvals for over 500 installations across Tamil Nadu — from 1 kWp home systems to multi-hundred kWp commercial projects. We manage the entire approval process, from Form NM submission to meter installation follow-up, so your project reaches energisation without unnecessary delays. Contact us for a consultation on your solar project and a clear roadmap through the TANGEDCO approval process.

TANGEDCO Solar Policy 2026 | Net Metering & Approval