Does Tamil Nadu offer net metering for factories and commercial consumers?
No. In Tamil Nadu, net metering is available only to domestic (residential) consumers. Factories and commercial consumers connect rooftop solar under net billing (net feed-in), where exports are credited at a TNERC feed-in tariff of ₹3.10 to ₹3.61 per kWh (by plant size) and imports are billed at your normal retail tariff.
TL;DR: The TNERC Grid Interactive Solar PV Regulations and Generic Tariff Order No. 8 of 2021 remain the operative framework. Homes get net metering up to sanctioned load. All other consumers (except hut and agriculture) get net billing up to sanctioned load or contracted demand, capped at 999 kW, with network charges of ₹1.27 per kWh (LT) or ₹0.83 per kWh (HT) on total generation. Gross metering starts at 151 kWp and is not open to LT consumers.
Last verified: 15 November 2026
- The three metering routes
- Feed-in tariffs and network charges
- Which route pays more for a factory
- Application process, fees and timelines
- Plants above 1 MW: the open access route
- What changed
- Frequently Asked Questions
The three metering routes
Tamil Nadu's solar metering framework comes from the TNERC Grid Interactive Solar PV Energy Generating System Regulations, 2021 (notified 20 October 2021) and Generic Tariff Order No. 8 of 2021 dated 22 October 2021. The utility (TANGEDCO, now TNEB Limited) circulated its implementation guidelines in December 2021, and its rooftop solar salient-features document summarises them.
| Route | Who is eligible | Capacity limit | How energy is credited | Network charge |
|---|---|---|---|---|
| Net metering | Domestic consumers only | Up to sanctioned load | Exported units offset imported units; surplus carried forward to 31 March, then lapses | Levied, with domestic discounts (see below) |
| Net billing / net feed-in | All categories except hut and agriculture, LT and HT | Sanctioned load or contracted demand, up to 999 kW, whichever is lower | Imports billed at retail tariff; exports credited at the feed-in tariff; net credit paid or carried forward at 31 March | LT: ₹1.27 per kWh; HT: ₹0.83 per kWh, on total generation |
| Gross metering | All categories except domestic (LT consumers not eligible) | 151 kWp to 999 kWp | All output sold to the licensee at the feed-in tariff; your own supply is billed separately | Not applicable |
Source: TANGEDCO salient features of TNERC Order No. 8 of 2021.
Two details matter for planning. First, gross metering needs a separate service line to the nearest HT feeder, laid and maintained at the owner's cost. Second, under both net-metering and net-billing routes, the network charge is levied on total generation recorded by the generation meter, not only on exported units. Our net metering vs gross metering vs net billing guide compares how these routes work across India.
Feed-in tariffs and network charges
The feed-in tariff is tiered by plant size, with a 20 per cent higher rate for evening-peak supply (6 pm to 9 pm) under the time-of-day provision:
| Plant size | Levelised feed-in tariff |
|---|---|
| 1 kW to 10 kW | ₹3.61 per kWh |
| 11 kW to 150 kW | ₹3.37 per kWh |
| 151 kW to 999 kW | ₹3.10 per kWh |
Network charges, as fixed in Order No. 8 of 2021, are ₹1.27 per kWh for LT prosumers and ₹0.83 per kWh for HT prosumers, charged on every unit the plant generates. Domestic prosumers pay a reduced rate (20 per cent of the charge up to 10 kW, 75 per cent above 10 kW), while all other categories pay the full charge.
Check the current orders. These are the 2021 baseline figures. TNERC revises tariffs and charges in its regular tariff orders, so confirm the prevailing feed-in tariff and network charge with the utility or the latest TNERC order before you build your financial model. Our Tamil Nadu open access charges guide tracks the corresponding open-access charges for larger plants.
Which route pays more for a factory
For most factories the value of solar comes from self-consumption, not exports. Every solar unit your plant uses on site replaces a unit bought at your retail HT tariff, which is worth far more than the export credit. Under net billing, each unit you do export earns the feed-in tariff minus the network charge.
Worked example for an HT consumer with a 500 kW plant in the 151-999 kW band, per exported unit:
- Feed-in tariff credited: ₹3.10 per kWh
- Network charge on generation: ₹0.83 per kWh
- Net export value: ₹3.10 minus ₹0.83 = ₹2.27 per kWh exported
The same unit consumed on site instead of exported avoids a purchase at your retail tariff, which is several times ₹2.27. That is why plant sizing should follow your daytime load, not the 999 kW cap. Our guide on sizing a solar plant for a factory walks through the load-matching method, and our roof structural load assessment guide covers the check that comes before any sizing decision.
Application process, fees and timelines
LT consumers apply online through the utility's rooftop solar portal at tnebltd.gov.in/usrp, choosing "Apply Online - CFA" (with central subsidy, for domestic systems) or "Apply Online - Non-CFA" (without subsidy). HT consumers apply to the Chief Engineer/NCES at NPKRR Maaligai, Chennai, with the latest HT bill, a project report with layout and single-line diagram, a completion timeline, proof of premises ownership, a no-due certificate and GST particulars.
Registration fees fixed in the regulation:
| Consumer category | Registration fee |
|---|---|
| LT, up to 20 kW | ₹500 |
| LT, above 20 kW up to 150 kW | ₹500 up to 20 kW, plus ₹100 for every 20 kW or part thereafter |
| HT, above 150 kW up to 500 kW | ₹5,000 |
| HT, above 500 kW up to 1 MW (999 kW) | ₹10,000 |
The regulation sets the utility's clock (salient features document):
- Registration acknowledged within 3 working days
- Technical feasibility report within 15 working days of registration
- Approval within 5 working days of a positive feasibility study; if not feasible, the reasons within 20 working days
- Approval valid for 6 months
- Testing and commissioning within 20 working days of your completion report
- Bidirectional meter installed and synchronised within 10 days after that
A safety certificate from the Chief Electrical Inspector to Government (CEIG) is part of the completion report where applicable; our CEIG approval guide explains what the inspection covers. Real durations run longer when a transformer needs upgrading or documents are incomplete, so build that slack into your project plan. After commissioning, the net export credit is settled in your bill each cycle, with any cumulative credit payable or carried forward at 31 March.
For what to check before signing the EPC contract that produces all these documents, see our solar EPC quote checklist and guide to choosing a solar EPC company.
Plants above 1 MW: the open access route
The net-billing cap of 999 kW is per consumer connection. If your load and roof or land can support a larger plant, Tamil Nadu's green energy open access framework lets consumers above the threshold contract for third-party or group-captive supply instead, under separate banking and surcharge rules. Our green energy open access rules guide explains the national framework, and the CapEx vs OpEx vs open access comparison shows when each route wins.
What changed
- 20 October 2021: TNERC notified the Grid Interactive Solar PV Energy Generating System Regulations, 2021.
- 22 October 2021: TNERC issued Generic Tariff Order No. 8 of 2021, fixing the feed-in tiers and network charges summarised above; TANGEDCO circulated implementation guidelines in December 2021.
- Since then: TNERC's periodic tariff orders have revised some charges, while the 2021 solar regulations remain the final solar-specific regulations listed by the Commission. Verify current figures against the latest order before finalising your model.
Frequently Asked Questions
Is net metering available for commercial consumers in Tamil Nadu?
No. Under TNERC Order No. 8 of 2021, net metering is only for domestic consumers. Commercial and industrial consumers use the net billing or net feed-in route, where imports are billed at the retail tariff and exports are credited at the feed-in tariff, or gross metering for HT consumers from 151 kWp.
What is the solar feed-in tariff in Tamil Nadu?
The 2021 baseline levelised feed-in tariff is ₹3.61 per kWh for 1-10 kW plants, ₹3.37 per kWh for 11-150 kW and ₹3.10 per kWh for 151-999 kW, with a 20 per cent higher rate for evening-peak supply between 6 pm and 9 pm. Confirm the prevailing rate in the latest TNERC tariff order.
What is the maximum system size under net billing?
Up to your sanctioned load or contracted demand, capped at 999 kW, whichever is lower. Domestic consumers can size up to their sanctioned load under net metering. Plants above these limits need the open access route or a different contracting structure.
What are network charges and how much do they cost?
Network charges compensate the distribution wires for hosting your plant. In the 2021 order they are ₹1.27 per kWh for LT prosumers and ₹0.83 per kWh for HT prosumers, charged on total generation, not only exports. Domestic prosumers pay a discounted rate; gross-metering plants pay none.
How long does TANGEDCO approval take?
The regulation sets: acknowledgement in 3 working days, feasibility in 15 working days, approval within 5 working days of a positive study, and commissioning within 20 working days of the completion report, with meter installation within 10 days after. Approvals are valid for 6 months. Practical timelines stretch when transformer upgrades or incomplete documents are involved.
Can LT consumers opt for gross metering in Tamil Nadu?
No. Gross metering is open to consumers of all categories except domestic, but LT consumers are not eligible. An LT factory's realistic option is net billing, with self-consumption doing the heavy lifting.
Ready to Go Solar?
Get a free consultation and custom quote for your industrial or commercial facility. Start saving on energy costs today.
Get Free Quote