STT GDC Navi Mumbai 4 is 36 MW under development, and the operator page keeps it outside the 133 MW Mumbai headline. That exclusion is honest and it also hides the size of what is coming. Thirty-six megawatts is 2.6 times the entire three-building Mumbai city portfolio, and it takes the Navi Mumbai node from 119 MW to 155 MW — 1.17 times the whole published portfolio, in four buildings inside one node. No basis, rack count, PUE or delivery date is published, so the pipeline is large and undated at the same time.
1At a glance
2Why it sits outside the headline
The arithmetic is clean, which is rare enough in this file to be worth spelling out.
| Building | MW | In the 133? |
|---|---|---|
| Mumbai 1 | 4 | yes |
| Mumbai 2 | 1 | yes |
| Mumbai 3 | 9 | yes |
| Navi Mumbai 1 | 28 | yes |
| Navi Mumbai 2 | 49 | yes |
| Navi Mumbai 3 | 42 | yes |
| Subtotal | 133 | exact match |
| Navi Mumbai 4 | 36 | no — under development |
Because the six sum to the headline to the megawatt, this building is provably additional. That is the good news. The bad news is that the operator never states the rule — so a reader cannot know whether "133 MW in Mumbai" means operating capacity, contracted capacity, or a set of cards that happened to add up on the day the page was built.
It is worth crediting the disclosure anyway. Most aggregates in this registry cannot be reconciled at all. This one can, and the excluded building is clearly excluded.
3What 36 MW does to one node
A single building changes the shape of the whole market at this scale.
| Measure | Today | With Navi Mumbai 4 |
|---|---|---|
| Navi Mumbai buildings | 3 in the headline | 4 |
| Navi Mumbai capacity | 119 MW | 155 MW |
| Share of the Mumbai portfolio | 89% | 117% of the current headline |
| Largest single building in the market | 49 MW, Navi Mumbai 2 | 60.5 MW, a Palava building |
| Racks at 8 kW | — | about 4,500 |
| Floor area at 100 W a sq ft | — | about 360,000 sq ft |
One building, 36 MW, and the node’s capacity grows by 30%. That is the scale Indian data centres now operate at — a single construction project is a fifth of a national portfolio.
For a buyer the number that matters is not 36. It is the date, and there is not one. A building of this size landing in 2027 and landing in 2029 are completely different supply stories for the Mumbai market.
4Procurement
5Limits and open questions
- No date of any kind. The single most important missing fact about the largest building in the pipeline.
- No basis, racks, floor area or PUE. The standard STT gaps.
- No stage detail. Under development could mean site clearance or a topped-out shell.
- Perimeter stated by arithmetic, not by the operator. The exclusion is provable because the six cards sum exactly, not because the page says so.
- Single source for the 36 MW.
- What would close it. A delivery date. One date would make this the most valuable record in the Mumbai pipeline.
6Sources
Sources: STT GDC India Mumbai city page, STT GDC India corporate site, STT GDC facility pages for Navi Mumbai, and Indian market commentary on Navi Mumbai data centre supply.