Rabale, Sify’s Mumbai 03 campus, is the operator’s largest site: five operational towers holding 96.94 MW of built IT power as of 30 June 2025, seven more towers designed, and a full-build figure of 377+ MW. The current portfolio card headlines it at 100 MW — which is 96.94 rounded, not a new number. A September 2024 brochure put the campus at 200 MW with a ten-tower plan; both the number and the tower count have since changed. This record is a campus aggregate and counts zero megawatts: the towers are counted on their own records, and adding the headline to them would double-count the same steel.
1At a glance
2One campus, five published figures
| Figure | Source and date | MW | Scope and notes |
|---|---|---|---|
| Design, full build | Current pages | 377+ | Twelve towers. Superseded the 200 MW brochure without explanation |
| Brochure | Sep 2024 | 200 | Ten-tower plan, 15,000+ racks, Tower 5 at 38.8 MW |
| Portfolio card | Oct 2026 | 100 | Current headline; equals 96.94 rounded |
| Built | 30 Jun 2025 | 96.94 | Five towers, per Sify Infinit Spaces |
| Factsheet | 2022 | 85 | Five towers, 10,000+ racks, plus 100 MW from three more |
| This registry | — | 0 | Campus aggregate; towers counted individually |
The headline is not a forward claim. 100 MW is 96.94 MW rounded up by 3.2%, and it describes five buildings that already exist. That makes Rabale unusual in this registry: most operators lead with a design number and bury the built one. Sify leads with the built one and buries the design number at 377 MW.
Which raises the more useful question. If 100 MW is the five-tower total, then 277 MW of the design figure sits in seven towers that do not yet exist — and Sify has been describing those towers since at least 2022, when a factsheet said three additional towers would add 100 MW of IT capacity.
In 2022 Sify said three more towers would add 100 MW. In 2026 the campus has five towers and the next four (6, 7, 11 and 12) are still described as becoming operational in 2026 — the same year, with no tower of that batch apparently live.
A 2022 brochure also said towers 6 and 7 would be operational in early 2025. They are still listed as upcoming.
Two schedule slips on the same two towers, four years apart. The design figure of 377 MW is credible as a site capability. It is not a schedule, and nothing in the public record supports treating it as one.
3The 200 MW that disappeared
The September 2024 Rabale brochure is the most detailed public document Sify has issued on this campus, and it contains a figure that appears nowhere in the 2026 record: 200 MW of IT capacity, on a ten-tower campus, with 15,000+ racks, 99 MW of solar and wind, and Tower 5 at 38.8 MW over 2,500+ racks. It also states that each tower is designed for up to 40 MW and 2,000+ racks.
| Item | September 2024 brochure | October 2026 pages |
|---|---|---|
| Campus IT capacity | 200 MW | 100 MW headline, 377+ MW design |
| Towers | 10 | 12 |
| Racks | 15,000+ | Not published on the campus card |
| Tower 5 IT power | 38.8 MW | 43.2 to 43.3 MW |
| Renewable share | Up to 79% | Up to 70% |
| Towers 6 and 7 | Operational early 2025 | Operational by 2026 |
None of these are errors in themselves — a plan can be revised. What they establish is that no single public figure for Rabale has survived four years unchanged, including the tower count and the renewable share, which both moved down.
The renewable share is the least-noticed item and the one with the largest commercial consequence. 79% to 70% is a 9-point drop in a claim that hyperscale tenants audit. Sify’s contracted green portfolio is 300+ MW nationally, so the direction is right; the campus-level percentage simply no longer matches the brochure that was used to sell it.
Ask for three numbers, not one: built, designed, and site ceiling. Rabale answers all three — 96.94, 377 and 12 towers. Most Indian campus announcements answer only the second.
Then check whether the headline equals the built figure. At Rabale it does, and that is a good sign: 100 MW is a statement about steel on the ground, not about a permit.
The weakness is entirely in the schedule, where the record shows two slips on the same towers. Capacity claims here are conservative. Delivery claims are not.
4Towers, substations and the twelve-tower plan
| Towers | State | Power and substation |
|---|---|---|
| Towers 1 to 3 | Operational | 110 kV on-premise substation |
| Tower 4 | Operational | 220 kV GIS substation |
| Tower 5 | Operational, G+8 | 220 kV GIS; designed for 43.3 MW |
| Towers 6, 7, 11, 12 | Stated operational by 2026 | 220 kV GIS serves towers 4 to 6 |
| Towers 8, 9, 10 | In planning | Each tower designed for up to 40 MW and 2,000+ racks |
The substation schedule is the most concrete evidence in the whole record and it deserves to be read closely. An operator does not build a 220 kV GIS switchyard for five towers. The 2022 factsheet described the 220 kV GIS as covering towers 4 to 10; the current page says towers 4 to 6. Either way, the switchyard was sized for a campus roughly three times the built capacity, and that is the strongest argument that the 377 MW design figure is a real engineering intent rather than a marketing ceiling.
It also sets the physical limit. At 40 MW a tower, ten towers is 400 MW and twelve is 480 MW — so 377 MW across twelve towers implies an average of 31.4 MW a tower, slightly below the stated per-tower design. The figures are coherent.
| Test | Result | Reading |
|---|---|---|
| Racks at 15 kW per rack | 25,133 | The 15,000+ rack brochure count covers built towers only |
| Racks at the 10 to 13 kW stated for towers 7 to 10 | 29,000 to 37,700 | Consistent with a twelve-tower campus |
| Built-to-design ratio | 26% | 96.94 of 377 MW — roughly one tower in four |
| Towers delivered of plan | 5 of 12 | 42%, over a plan that dates to at least 2022 |
Rabale is about a quarter built against its own design figure. That single ratio is the most useful thing on this page for anybody modelling Sify’s capacity: the campus can absorb roughly 280 MW of further investment, at the replacement band of ₹51.4 to 60.1 crore per MW, which is between ₹14,400 crore and ₹16,800 crore of future capex on one Navi Mumbai address. Both are arithmetic on published figures, not forecasts.
5Ninety-nine megawatts of green power
Rabale contracts 99 MW of solar and wind, described as delivering up to 70% renewable share. Against 96.94 MW of built IT power that is roughly 1.02 MW of green generation per MW of IT — a ratio worth understanding, because it is not what it looks like.
A data centre drawing 96.94 MW of IT load at a power usage effectiveness of 1.5 draws about 145 MW from the grid. Ninety-nine megawatts of contracted renewable energy covers roughly 68% of that total draw — which is almost exactly the 70% claim, and means the renewable percentage is measured against total facility draw, not IT load. The two numbers corroborate each other.
| Item | Value | Basis |
|---|---|---|
| IT power built | 96.94 MW | Sify Infinit Spaces, 30 June 2025 |
| Estimated total draw at PUE 1.5 | 145 MW | Estimate; Sify does not publish a PUE for Rabale |
| Contracted solar and wind | 99 MW | Operator, campus page |
| Renewable share implied | 68% | 99 of 145 MW — matches the stated up-to-70% claim |
| Stated share | Up to 70% | Brochure said 79%, current page says 70% |
This is the one place in the Rabale record where the numbers close. The renewable claim is arithmetically consistent with the built capacity and a standard PUE. Given how much of the rest of the record has moved, that consistency is worth recording.
It is also the number that will decide whether Rabale wins hyperscale tenants in the second half of this decade. India’s large buyers increasingly procure on renewable share and hourly matching, not on megawatts. A campus at 70% contracted renewable is competitive; a campus that must add 280 MW of future load against the same 99 MW of green supply will need a new power purchase agreement for every tower.
6Procurement
7Limits and open questions
- Five published capacities — 85, 96.94, 100, 200 and 377 MW. The registry counts zero because the towers are counted individually and this is an aggregate.
- 96.94 MW is dated 30 June 2025 and is the only measured figure. The 100 MW headline is undated and equals it rounded.
- The 200 MW figure is withdrawn without explanation. The tower count also moved from ten to twelve, and the renewable share from 79% to 70%.
- Towers 6 and 7 have slipped at least once — promised for early 2025 in a 2024 brochure, still upcoming in 2026.
- No PUE is published for Rabale. The 1.5 used in the energy arithmetic is an estimate and is labelled as one.
- 96.94 MW may include Tower 5 at design rather than installed power. It is addressed on PRJ-222 and is the most consequential open item in the Sify family.
- What would close it. A tower-by-tower schedule with megawatts, energisation dates and installed load.
8Sources
Sources: the Sify Rabale data centre page and its 96.94 MW, 43.2 MW and 377-plus MW specifications; the Sify data centre portfolio page; Sify Infinit Spaces Mumbai data centre page dated 30 June 2025; the Sify Europe data centre pages; the Rabale brochure of September 2024 and the MUM03 factsheet of 2022; the Tower 5 to Tower 10 factsheet; and third-party specifications from DataCenters.com, Baxtel and ArusGrid.