In short
- What you pay now: HT III commercial buildings pay ₹9.40 a unit (₹11.75 at 6–10 am and 6–10 pm) plus ₹608 per kVA a month and 5% electricity tax. A unit that solar replaces costs you about ₹10.24.
- Rooftop and car-park solar: usually the cheapest unit you can get. With our zero-investment model you put in no capital and pay only for the units you use.
- Open access: for HT connections of 63 kVA or more. At an assumed ₹4.00 solar price, power lands at about ₹7.57 through third-party and about ₹5.66 through group captive.
- Battery storage: can cut air-conditioning demand spikes and back up critical loads.
- Our offer: send your last three EB bills. You get a one-page cost sheet within two working days.
Rates are from TNERC Tariff Order No. 6 of 2025 and were still in force on 11 October 2026. The order allows an inflation-linked rise of up to 6% from 1 July each year; the 2026 rise has not been ordered. Illustrative default values — request a site-specific quotation.
Find your type of building
Daytime load, holiday months
Solar matches class hours. We size it to term time so the summer holidays don't waste it.
Solar for schools and colleges HospitalsRound-the-clock load, backup
Solar for the day, open access or wind for more, and a battery to cut diesel running.
Solar for hospitals IT parks & corporate officesBig daytime load, green reporting
Large, steady daytime demand and a need to show renewable power in annual reports.
Solar for IT parksHighest tariff, AC spikes
HT III rates, a 5% lighting add-on for many, and big afternoon air-conditioning peaks. Read on below.
What each kind of building pays TNEB
| TNEB category | Who | Energy charge | Unit solar replaces |
|---|---|---|---|
| HT III | Malls, hotels, offices (government and private), private hospitals, banks, cinemas | ₹9.40 | ₹10.24 |
| HT IIB | Private schools and colleges that are not government-aided | ₹8.25 | ₹8.99 |
| HT IIA | Government and government-aided schools and colleges, government hospitals, trust hospitals that treat everyone free, NABH hospitals in village or town panchayat areas | ₹7.75 | ₹8.04* / ₹8.44 |
| HT I | Companies doing IT services, such as software, BPO and data centres (and factories) | ₹7.50 | ₹8.17 |
Three ways to cut the bill
1. Solar on your roof or car park. Power made and used on your own premises skips transmission, wheeling, the surcharges and line losses, so it is usually the cheapest unit you can get. Grid-connected rooftop plants can still carry network charges set by TNERC; we put whatever applies into your numbers. Malls and offices with big car parks can add solar car-park sheds. With our zero-investment model, we fund, build and run the plant, and you pay an agreed rate per unit. The agreement usually runs many years, so read the exit terms first (what to check).
2. Open access or group captive. If your HT connection is 63 kVA or more, you can buy solar or wind power from a plant elsewhere. Because the HT III rate is high, both routes save well for commercial buildings: at an assumed ₹4.00 solar price, about ₹7.57 a unit through third-party and about ₹5.66 through group captive, against ₹10.24 from TNEB. See every charge worked out →
3. Battery storage. Air-conditioning pushes up your demand, and TNEB bills the higher of your highest 15-minute demand or 90% of your contracted demand, so a battery only saves money on demand above that floor. It can also back up critical loads. When a battery pays →
Illustrative default values — request a site-specific quotation. Open access figures assume a 33 kV solar plant supplying an 11 kV connection, with line losses, wheeling, transmission, scheduling, cross-subsidy surcharge and electricity tax counted. They leave out the additional surcharge (none ordered for power used after 30 September 2025; TNPDCL has proposed ₹0.63 a unit on third-party power from October 2026, which would make HT III about ₹8.20 and HT IIB about ₹8.12), Aran's facilitation fee, and, for group captive, the cost of your equity.
Malls, hotels and offices: what to watch
- The 5% lighting add-on. Many commercial establishments, marriage halls and convention centres pay 5% more on energy unless their lighting is on a separate connection. That makes each solar unit worth more.
- Daytime and evening load. Office air-conditioning load rises with the sun. Malls and hotels also have a large evening load that rooftop solar can't cover.
- Roof space. Mall and office roofs are often crowded with chillers and water tanks. Car-park sheds and open access cover what the roof can't.
How we work
- You send your last three EB bills on WhatsApp, and tell us your roof and car-park space.
- Within two working days you get a one-page sheet: your cost today, with rooftop solar, open access and group captive, for your tariff and voltage.
- We visit, confirm the roof and the load, and give you a firm proposal.
- We build or arrange the supply and handle the TNPDCL approvals.
How we're paid for open access deals: a small facilitation fee on each unit delivered, shared by the generator and the buyer and agreed in writing before anyone signs. We never buy or resell the power.
Common questions
Can a commercial building get solar with zero investment?
Yes. With our zero-investment model we fund, build and run the solar plant on your roof or car park, and you pay an agreed rate for each unit you use. You own nothing and put in no capital. The agreement usually runs many years, so read the exit terms first.
Can a mall or office take open access in Tamil Nadu?
Yes, if it is on an HT connection with a contracted demand of 63 kVA or more. Commercial buildings on HT III usually save more per unit than factories, because their TNEB rate is higher.
What does a commercial building pay TNEB per unit?
HT III commercial buildings pay ₹9.40 a unit, 25% more from 6–10 am and 6–10 pm, plus ₹608 per kVA a month and 5% electricity tax (TNERC Tariff Order No. 6 of 2025). A unit that solar replaces costs about ₹10.24. Illustrative default values — request a site-specific quotation.
Is our building on HT or LT?
It is printed on your EB bill. Larger buildings are usually HT. LT buildings can still have rooftop solar, but cannot take open access in Tamil Nadu.
Get a free check for your building
Tell us about your building. The quickest way is to WhatsApp your last three EB bills; we come back within two working days. No obligation.
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