Tamil Nadu electricity rates
TNEB Tariff Rates 2026-27
The exact TANGEDCO slab rates our solar calculator uses — domestic and commercial, bi-monthly billing, with the 100 free units subsidy. No guessed numbers.
Domestic (LT-I A) — homes
Billed once every two months. The first 100 units per cycle are free when the total stays within 500 units.
| Bi-monthly consumption | Rate per unit |
|---|---|
| 0 – 100 units | ₹4.95 |
| 101 – 200 units | ₹4.95 |
| 201 – 400 units | ₹4.95 |
| 401 – 500 units | ₹6.65 |
| 501 – 600 units | ₹8.80 |
| 601 – 800 units | ₹9.95 |
| 801 – 1,000 units | ₹11.05 |
| Above 1,000 units | ₹12.15 |
Above 500 units per cycle the free-units subsidy no longer applies and every unit is billed at the slab rates — which is why high-usage homes benefit the most from rooftop solar.
Commercial (LT-V) — shops & businesses
Flat energy rate plus a fixed charge per kW of contracted load and electricity duty.
| Charge | Rate |
|---|---|
| Bi-monthly bill up to 200 units | ₹6.65 / unit |
| Bi-monthly bill above 200 units | ₹10.45 / unit (all units) |
| Fixed charge | ₹110 / kW / month |
| Electricity duty | 5% on energy + fixed charges |
Network charges — the extra line solar consumers see
Once a rooftop solar system is grid-connected, TNERC's GISS Order No. 8 of 2021 levies a network charge on the total generation recorded in the solar meter (it replaced the old parallel operation charge). It keeps the grid available for your power to flow in and out.
| Consumer / mechanism | Network charge |
|---|---|
| Domestic net metering — system up to 10 kW | 20% of ₹1.53 ≈ ₹0.31 / kWh of total generation |
| Domestic net metering — above 10 kW | 75% of ₹1.53 ≈ ₹1.15 / kWh of total generation |
| Other LT categories (net feed-in) | ₹1.53 / kWh of total generation |
| HT consumers (net feed-in) | ₹0.96 / kWh of total generation |
| MSME rooftop solar (50% waiver) | ₹0.765 / kWh of total generation |
| Gross metering | Nil |
Real example: a 5 kW domestic rooftop system generates roughly 1,350 units per bi-monthly cycle. At the 20% rate (₹0.306/unit) the network charge is about ₹410 per cycle — a small fraction of the ₹10,000+ TNEB bill the same system replaces, so solar savings stay far ahead of this charge.
In December 2023 TNERC also approved a 50% network-charge waiver for rooftop solar MSMEs (₹1.53 → ₹0.765 per kWh), with the state government bearing the balance.
What this means for your solar savings
Solar offsets your most expensive units first. A home using 600 units per cycle pays up to ₹12.15 for the top units, so every solar unit saves far more than the average rate. Our calculator applies these exact slabs to your usage — try it with your last TNEB bill.
Calculate my savingsCommon questions on TNEB billing
How many units are free in TNEB domestic tariff?
The first 100 units per bi-monthly billing cycle are free for domestic consumers whose total consumption stays within 500 units per cycle.
What is the TNEB commercial rate per unit in Tamil Nadu?
Commercial (LT-V) connections pay ₹6.65 per unit when the bi-monthly bill stays within 200 units, and ₹10.45 per unit for all units above that, plus a fixed charge of ₹110 per kW per month and 5% electricity duty.
Why does solar save more for high-usage homes?
TNEB domestic tariffs are telescopic: units above 500 per bi-monthly cycle cost ₹8.80 to ₹12.15 each. Solar offsets the most expensive units first, so homes with higher bills see the fastest payback.
What are TNEB network charges for rooftop solar consumers?
Per TNERC's GISS Order No. 8 of 2021, LT rooftop solar consumers pay a network charge of ₹1.53 per kWh on total solar generation (₹0.96 per kWh for HT net feed-in). Domestic net-metering homes pay only a part of it — 20% (about ₹0.31 per kWh) for systems up to 10 kW and 75% (about ₹1.15 per kWh) above 10 kW. Gross-metering consumers pay no network charges.
How much network charge does a typical Trichy home pay on rooftop solar?
A 5 kW domestic rooftop system generating about 1,350 units per bi-monthly cycle pays roughly ₹410 in network charges at the 20% rate — a small fraction of the ₹10,000+ TNEB bill it replaces, so solar savings stay far higher than this charge.
Rates per the latest TNERC tariff order for 2026-27 and TNERC GISS Order No. 8 of 2021. TANGEDCO may revise tariffs; we update this page and the calculator together when they do.
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