STT GDC India publishes a Mumbai city headline of 133 MW. It is not an estimate — it is exactly the sum of six building cards the company also publishes: 4, 1, 9, 28, 49 and 42 MW. That precision is rare in this registry and worth crediting. It also shows what the number is made of: 89% of it is in Navi Mumbai, 14 MW is in Mumbai city, and one of those Mumbai buildings is a single megawatt. The 36 MW under construction at Navi Mumbai 4 is excluded, the 400 MW Palava campus is separate and three times larger, and the whole 133 MW contributes nothing to the Maharashtra total.
1At a glance
2The 133 is exactly six cards
Most portfolio headlines in this registry cannot be reconciled to anything. This one can, which makes it the best-behaved aggregate in the file.
| Building | MW | Cumulative | Stage stated |
|---|---|---|---|
| Mumbai 1 | 4 | 4 | unverified |
| Mumbai 2 | 1 | 5 | unverified |
| Mumbai 3 | 9 | 14 | unverified |
| Navi Mumbai 1 | 28 | 42 | unverified |
| Navi Mumbai 2 | 49 | 91 | unverified |
| Navi Mumbai 3 | 42 | 133 | unverified |
| Headline | 133 | exact match | — |
Six cards, one sum, no rounding. After four pages of CtrlS aggregates that do not reconcile and two parks that cannot be confirmed at all, this is the standard the rest of the file should be held to.
The cost of that honesty is visible too. Six cards reconcile, but not one of them states a stage. Every building is marked stage unverified in this registry because the operator page does not say which are live, which are filling and which are shells. A portfolio you can add up is not the same as a portfolio you can trust the status of.
3Eighty-nine per cent is Navi Mumbai
Called the Mumbai city portfolio, it is in practice a Navi Mumbai portfolio with a small city tail.
| Measure | Mumbai city | Navi Mumbai | Reads as |
|---|---|---|---|
| Buildings | 3 | 3 in the headline, 1 more building | a city tail and a suburban base |
| Capacity | 14 MW | 119 MW | 89% suburban |
| Average building | 4.7 MW | 39.7 MW | the city sites are legacy scale |
| Smallest | 1 MW | 28 MW | one building is a single suite |
| Largest | 9 MW | 49 MW | Navi Mumbai 2 is 3.5 times the whole city trio |
This split matters for anyone pricing Mumbai capacity, because Mumbai city and Navi Mumbai are different products. City sites are close to customer premises and legacy enterprise, low-density and small. Navi Mumbai is where hyperscale halls, fibre landings and the new builds sit.
Quoting a single "Mumbai 133 MW" hides that difference. Half a dozen market notes in this file quote it, and none of them say that 14 of those megawatts are three small city buildings.
4What is excluded
A portfolio headline is only as useful as its perimeter, and this one has a clear edge to it.
| Record | MW | Inside the headline? | Why |
|---|---|---|---|
| Mumbai 1, 2 and 3 | 14 | yes | published city cards |
| Navi Mumbai 1, 2 and 3 | 119 | yes | published city cards |
| Navi Mumbai 4 | 36 | no | listed as under development on the same page |
| Palava 1 | 50 | no | separate campus, tracked as PRJ-061 |
| Palava 4 and 5 | 121 | no | separate campus, tracked as PRJ-061 |
So the operator’s own disclosure set is 133 MW in the headline, 36 MW in development on the same page, and a separate Palava campus with 400 MW of design capacity. Total Maharashtra exposure: roughly 569 MW when the campus is included.
The distinction is not pedantry. A buyer sizing 2029 supply needs the 569, not the 133, and a state-level market number needs only the operating part, which is something less than 133 because the stage of each building is unstated.
5The next wave is bigger than the portfolio
Palava is the reason this portfolio page will look small in two years.
| Current portfolio | Palava campus | |
|---|---|---|
| Capacity | 133 MW | 400 MW design |
| Buildings | 6 | 3 cards published: 50, 60.5, 60.5 MW |
| Status | operating, stage unverified | groundbreaking March 2026, first 50 MW phase |
| Land | established sites | 46 acres inside a planned data centre park |
| Record | PRJ-108 | PRJ-061 |
Palava is three times the current portfolio at design capacity, and the first phase alone is 50 MW — bigger than Navi Mumbai 2, the largest building in the current estate. Full detail is on PRJ-061.
The consequence for this record: the 133 MW is a legacy portfolio being overtaken. Anything built on the current number for a 2028 supply forecast will be wrong by the size of the new campus.
6Who owns it now
The ownership changed in September 2026, and it changes the read on the numbers above.
| Item | Position |
|---|---|
| Parent | STT GDC, acquired by a KKR-led consortium with Singtel |
| Deal | About $5.2 billion for roughly 82%. KKR around 75%, Singtel around 25% |
| Completed | September 2026 |
| What it means | A financial owner with a five to seven year horizon, which usually accelerates buildout and then seeks an exit |
| Implication for capacity | buildout gets faster, not slower — Palava and Navi Mumbai 4 are the proof of intent |
| What it does not change | The disclosure. Nothing in the ownership change adds a rack count, a PUE or a per-building status |
Private equity ownership of Indian data centre platforms is now the norm rather than the exception, and it has a predictable effect on the public record: capital announcements get louder and technical disclosure stays thin. STT is a good example. A $5.2 billion transaction and still no rack count on any Indian building.
7Procurement
8Limits and open questions
- No stage per building. All six are marked unverified because the operator page does not date them.
- No basis. Not one card says IT load or gross capacity.
- No rack counts, no floor areas, no PUE. Density is not computable anywhere in this portfolio.
- Perimeter questions remain. Navi Mumbai 4 and the Palava cards are clearly outside the headline, but the operator does not state the rule.
- Company-level figure is separate. The over 400 MW in operation and development across 10 cities is not a Mumbai number and is not used here.
- What would close it. A per-building status table. The company clearly has one internally.
9Sources
Sources: STT GDC India Mumbai city page, STT GDC India corporate site, STT GDC facility pages for Mumbai and Navi Mumbai, Data Center Dynamics on the Palava groundbreaking and on the KKR and Singtel acquisition, and Indian market commentary on the Mumbai data centre market.