AirTrunk MAA1 at Ambattur is 128 MW of facility capacity on 6.6 hectares, with a 230 kV substation and a declared design PUE below 1.4. The land is real: Lumina reportedly acquired a 16-acre parcel in Ambattur in 2026, and AirTrunk’s card describes 6.6 hectares, which is 16.3 acres. The two figures agree. If built, MAA1 would be the largest single data centre in Chennai — bigger than CtrlS’s 72 MW park, Iron Mountain’s 42 MW campus, NTT’s 34.8 MW Chennai 2 and CapitaLand’s 34 MW, in a suburb that already publishes more than 300 MW across five operators. That is the interesting fact about this site. It is not a frontier location. It is one of the most contested industrial estates in India, and 128 MW is being added to a corridor that has been building since 2020 on the same 230 kV and 400 kV grid. Stage unverified, as with every card in the pipeline.
1At a glance
2300 MW in one suburb
AirTrunk is not entering an empty market here. Ambattur is the most built-up data centre estate in Tamil Nadu.
| Operator | Capacity | Status | Note |
|---|---|---|---|
| AirTrunk MAA1 | 128 MW | unverified | 6.6 ha, 230 kV |
| CtrlS Chennai park | 72 MW | operational and building | two buildings, 1 million sq ft |
| Iron Mountain CHN-1 and 2 | 42 MW | CHN-1 topped out | 23.2 MW in the first building |
| NTT Chennai 2 | 34.8 MW | 17.4 MW live | two 9-storey buildings |
| CapitaLand, Clint | 34 MW | opened October 2026 | 13 data halls |
| Total published | 310.8 MW | — | in one industrial suburb |
Three hundred and ten megawatts in one suburb. For scale, that is 12.8% of everything this registry counts across all 242 records and every state in India, sitting inside a few square kilometres of Ambattur.
Four of those five operators have dated, physical evidence — a topping out, an opening, a commissioning. AirTrunk is the only one whose stage is unknown.
The commercial read is straightforward. Ambattur is proven, has grid capacity at 230 kV, and has 300 MW of neighbours, which matters to tenants buying interconnect. It is also the reason Chennai’s published capacity in this registry is 296.6 MW while the suburb alone publishes 310.8 — the state’s own records and the operators’ marketing are measuring different things.
When a single industrial estate publishes more capacity than an entire state’s counted total, the market’s numbers are not describing the same thing.
The registry counts 296.6 MW for Tamil Nadu because it counts buildings with a stated basis. Ambattur’s 310.8 MW is mostly plans and headlines.
3230 kV, and what a corridor can carry
The substation is the only part of this record with an independent check, and it is consistent.
| Measure | Value | Basis |
|---|---|---|
| Facility capacity | 128 MW | operator card, at least |
| Site area | 6.6 ha / 16.31 acres | operator card |
| MW per acre | 7.85 | 128 divided by 16.31 |
| Power | 230 kV substation | operator card |
| Design PUE | below 1.4 | operator card |
| Compare NTT Chennai 2 | 34.8 MW on 6 acres | 5.8 MW per acre |
| Compare Keppel / CapitaLand Ambattur | 34 MW in 13 data halls | 600,000 sq ft on four acres |
At 7.85 MW an acre, MAA1 is denser than NTT’s Chennai 2 (5.8) and less dense than the AirTrunk Mumbai sites (9.0 to 12.9). That is the Chennai land market showing: Ambattur is expensive but not Chandivali-expensive, so the building can spread out a little.
Two hundred and thirty kilovolts in a corridor that already carries CtrlS, Iron Mountain, NTT and CapitaLand is the real constraint. Every one of those operators is drawing from the same state transmission network, and Tamil Nadu has been one of the more active states in adding capacity for data centres — but 310 MW becoming 440 MW in one suburb is a grid question before it is a construction question.
Which is the honest assessment of this record: the land exists, the substation voltage is published, the efficiency target is declared, and the only thing standing between the card and a building is power and demand.
4Procurement
5Limits and open questions
- Stage is unverified. No operating or construction status is published on the operator card.
- 128 MW is facility capacity, at least — not IT load.
- The 16-acre parcel acquisition is reported, not confirmed by AirTrunk as the MAA1 site. The acreage is consistent with the card’s 6.6 ha, which supports the link without proving it.
- Design PUE below 1.4 is a specification, not an operating measurement.
- No floor area, rack count, tenant list or occupancy.
- The Ambattur total of 310.8 MW mixes dated operator statements with an unverified card and is indicative only.
- What would close it. A construction start and a power allocation. Two facts would turn this from the largest card in Chennai into the largest building.
6Sources
Sources: AirTrunk location page for MAA1, AirTrunk’s announcement of the Lumina CloudInfra acquisition, Data Center Dynamics coverage of the acquisition and of the reported Ambattur land purchase, Data Center Dynamics reporting on the CtrlS Chennai park, Iron Mountain’s Chennai campus material, NTT’s Chennai 2 record in this registry, and CapitaLand India Trust’s October 2026 Chennai launch coverage.