The Colt DCS and RMZ joint venture committed US$1.7 billion in November 2024 to build 250 MW of data centre capacity across Mumbai and Chennai. That is US$6.8 million per megawatt — ₹60.1 crore — the highest disclosed programme rate in this registry. At the Navi Mumbai campus, Mumbai 1 and Mumbai 2 run 22 MW. Mumbai 3 adds 64 MW of AI-ready capacity with a 220 kV GIS substation on site, taking the campus to 86 MW against a potential 148 MW. Construction began on 15 October 2026, and the building was fully pre-let before it started — the first hyperscale customer signed and not named.
1At a glance
2US$6.8 million per megawatt, the top of the market
| Programme | Rate per MW of IT | ₹ crore per MW | Basis |
|---|---|---|---|
| Colt DCS–RMZ | US$1.7bn for 250 MW | ₹60.1 crore | Two cities, multiple buildings |
| CapitaLand Chennai 01 | ₹1,940 cr for 34 MW | ₹57.1 crore | Single building, four acres |
| AirTrunk India | US$6.0m per MW | ₹53.0 crore | Five sites, 601 MW |
| NTT NAV2 phase one | ₹5,500 cr for 107 MW | ₹51.4 crore | Four data centres, 54 acres |
| NTT Bengaluru 4 | ₹2,400 cr for 67.2 MW | ₹35.7 crore | Three buildings, 8.5 acres |
| Market band | — | ₹51.4 to ₹60.1 crore | A 17% spread |
Being at the top of a 17% band is not a red flag. It is a description of what this programme buys: urban infill land in Navi Mumbai and Ambattur, 220 kV power, and a fully pre-let building in an AI-ready configuration. All three of those cost more than a greenfield campus in Devanahalli.
The comparison that matters commercially is NTT Bengaluru 4 at ₹35.7 crore per megawatt — 41% cheaper. That is not an efficiency gain by NTT. It is the difference between three buildings on 8.5 acres of Devanahalli land and two buildings on constrained parcels in the two most contested data centre corridors in India.
A 41% spread between the cheapest and most expensive disclosed Indian build is a land and power spread, not a construction spread. Contractors charge similar rates in both cities.
That means the per-megawatt cost of Indian data centre capacity is a function of where far more than how. Which is why the land-efficiency ratio, megawatts per acre, is the single most predictive number in this registry.
A tenant paying rent in Navi Mumbai is paying for a substation and a fibre route that Devanahalli does not have. That is the whole premium.
3Twenty-two, then eighty-six, then one hundred and forty-eight
| Stage | MW | Evidence |
|---|---|---|
| Mumbai 1 and Mumbai 2 | 22 | Live since September 2023 |
| Mumbai 3 at completion | 64 | Construction began 15 October 2026; fully pre-let |
| Campus at Mumbai 3 completion | 86 | Company statement |
| Remaining campus potential | 62 | Undated, unbuilt, undesigned |
| Campus at full development | 148 | Company statement |
| JV programme across Mumbai and Chennai | 250 | US$1.7 billion commitment |
| Implied Chennai and third-site allocation | 102 | Derived: 250 − 148 |
Only 15% of the programme is running. One building — Mumbai 3 at 64 MW — takes the campus from 22 MW to 86 MW, a 2.9-fold increase, and it is the only facility in the programme with a construction date attached.
The remaining 62 MW of campus potential and the 102 MW implied for Chennai and a third site have no buildings, no dates and no designs. For a JV that has been running since November 2024, two years with one building under construction is a slow start — and it is a more useful fact than the US$1.7 billion headline.
4Fully pre-let before construction
This is the most commercially significant sentence in the announcement, and it is easy to read past: Mumbai 3 was fully pre-let before construction started.
| Implication | Holds | Why it matters |
|---|---|---|
| Revenue is contracted before capital is spent | Yes | The JV is not building speculatively |
| The customer is a hyperscaler | Yes | Named by neither party |
| 64 MW is described as secured contracted power | Yes | The megawatts are sold, not available |
| The building is AI-configured | Yes | Hybrid air plus direct liquid-to-chip cooling |
| Which means a specific rack density | not disclosed | Liquid cooling implies above 30 kW per rack |
| Commercial terms and term length | not disclosed | The number that would price this asset |
| Identity of the tenant | not disclosed | Concentration risk cannot be assessed |
A fully pre-let building is a different asset class from a speculative one. It is financeable at construction cost, it carries a named counterparty for the term, and its value is set by the lease rather than by the market.
The absence of the tenant name and the lease term is the whole gap. Sixty-four megawatts of AI-ready capacity in Navi Mumbai is pre-sold, and the market does not know to whom or for how long.
The engineering is also more specific than most. A 220 kV GIS substation on campus is the same voltage class as NTT’s Mumbai builds and AirTrunk’s Airoli and Mahape sites, and it is what 64 MW requires. The closed-loop cooling design with near-zero wastewater is a real differentiator in a city where water for cooling is contested.
5The Ambattur overlap
| Record | MW | Basis |
|---|---|---|
| AirTrunk MAA1 (PRJ-183) | 128 | Facility, at least; stage not stated |
| Colt DCS–RMZ Chennai allocation | up to 102 | Derived; not separately disclosed |
| CtrlS Chennai park | 72 | Published capacity |
| Iron Mountain Chennai | 42 | Announced, two buildings |
| NTT Chennai 2 (PRJ-167) | 34.8 | IT, live |
| CapitaLand Chennai 01 (PRJ-198) | 34 | IT, tenant-ready end-2026 |
| Published in the corridor today | 310.8 | Excluding Colt DCS–RMZ |
| With this JV’s Chennai share | up to 412.8 | Upper bound |
| Tamil Nadu counted in this registry | 296.6 | IT load, additive rows |
Up to 412.8 MW published in one industrial suburb, against 296.6 MW counted across the whole of Tamil Nadu. Ambattur is, on published numbers, larger than the state that contains it.
Six operators on one corridor is a different competitive dynamic from a market with one dominant park. It means the interconnection fabric and the local substations are shared infrastructure, and it means a tenant has real choice without leaving the district — which compresses rent.
It also means the corridor’s published figure is composed almost entirely of facility capacity and unverified stages. The only IT-load figures in the list are NTT's 34.8 MW and CapitaLand's 34 MW — 68.8 MW of the 310.8. Everyone else is quoting a bigger number on a looser basis.
When six operators stack into one corridor, the published number becomes a marketing equilibrium rather than a measurement. Each one has to be at least as large as the last announcement.
The two operators that publish IT load are the two that look smallest. They are not smaller; they are measured.
That single effect is worth more to a buyer than any individual capacity figure in this file.
6Procurement
7Limits and open questions
- US$1.7 billion is a programme commitment, not a facility cost. No capex is disclosed for Mumbai 3.
- No completion date is given for Mumbai 3 by either party.
- The tenant is not named, and no lease term is published, so concentration risk cannot be assessed.
- 22 MW is derived by subtracting Mumbai 3’s 64 MW from the stated 86 MW campus figure. It is not separately disclosed.
- The Chennai and third-site allocation of up to 102 MW is derived from 250 minus 148 and is not a disclosed figure.
- Vizag is reported, not confirmed, and is not in the 250 MW programme as announced.
- Appendix: the 250 MW is a target across all phases in two cities and is never additive to a state or national total in this registry.
- What would close it. A tenant name, a lease term and a completion date.
8Sources
Sources: the Colt DCS and RMZ joint venture release of 19 November 2024; the Mumbai 3 construction announcement of 15 October 2026; PR Newswire, Yahoo Finance and ET Datacenters coverage of both; Datacenter Magazine on the pre-let; VCCircle on the joint venture structure; and the Colt DCS ownership and investment page.