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CARTIS

STACK MIL01 Siziano Campus

Siziano / Milan market, Italy · 25Operating
Evidence
Planned critical IT
27 MW
Updated
Oct 28, 2026
Utility
Milan Internet Exchange (MIX) · Terna

STACK's current MIL01 campus in Siziano comprises three operating buildings totaling 27 MW. Older STACK and SUPERNAP releases describe broader Milan/Siziano scopes and expansion potential, so those figures are not added to the current MIL01 record.

Capacity

Campus capacity

Actual

27 MW

Source

Building capacity

Actual

12 MW

MIL01A · Phase

Phase scope; not a whole-site figure

Source

Building capacity

Actual

12 MW

MIL01B · Phase

Phase scope; not a whole-site figure

Source

Building capacity

Actual

3 MW

MIL01C · Phase

Phase scope; not a whole-site figure

Source

Operating IT capacity: Not established in published records

A missing figure does not mean zero. Planned, utility and generation figures are not operating IT capacity.

Development

MIL01AOperational

1 building

12 MW building within the current 27 MW MIL01 boundary.

MIL01BOperational

1 building

12 MW building within the current 27 MW MIL01 boundary.

MIL01COperational

1 building

3 MW building within the current 27 MW MIL01 boundary.

Legacy Siziano/Milan expansion contextChanged or cancelled

The 40 MW, 50+ MW, 75 MW, 80+ MW and 299 MW figures describe broader or later development scopes rather than current MIL01 capacity.

Milestones (4)
Sirti/Terna HV connection program announced

Jun 8, 2021 · Recorded actual event

Completed · Announced

Source not linked
Second facility on legacy Milan campus opened

Nov 23, 2021 · Recorded actual event

Completed · Commercial operation

Source not linked
Third data center on legacy Milan campus opened

Jul 27, 2022 · Recorded actual event

Completed · Commercial operation

Source not linked
USD 1.2b financing benefits Milan campuses

Apr 9, 2024 · Recorded actual event

Completed · Financing

Source not linked

Participants

IPI Partners

Investor

Sources by role
Investor (1)
STACK Infrastructure

Operator

Sources by role
Operator (1)
Other participants (5)
Comune di Siziano

Government authority

Sources by role
Government authority (1)
EPI

Contractor

Sources by role
Contractor (1)
Milan Internet Exchange (MIX)

Utility provider

Sources by role
Utility provider (1)
Sirti

Contractor

Sources by role
Contractor (1)
Terna

Utility provider

Sources by role
Utility provider (1)
Utility provider (1)

Capital & incentives

Financing records

Debt financing

$1.2bn

Apr 9, 2024

Benefits STACK Milan campuses; no MIL01-only allocation disclosed.

Parties & sources

STACK Infrastructure (Borrower)

Sources (1)

Site & development

Land area

Actual

25 acres

Source

Building count

Actual

3 buildings

Source

Technical specifications

Energy claim

Actual

100% Certified green energy

Source

Additional project facts

Operational status

Actual

Operating

Source

Dedicated high voltage substation

Actual

Present

Source

Infrastructure & permits

Technical details (5)
Electric grid

Operational

27 MW

Current MIL01 campus capacity across three buildings.

Electric grid

Operational

Dedicated high-voltage substation on the current MIL01 page.

Electric grid

Reported context

80 MW up to

On June 8, 2021, STACK and Sirti announced a partnership for Sirti to develop a high-voltage line and HV/MV substation connecting the campus to Terna, for up to 80 MW. This is the broader campus power scope, not proof of completed delivery or MIL01 IT capacity.

Fiber

Reported context

Historical broader campus proximity/connectivity to MIX.

Renewable energy supply

Operational

100 %

Operator claimed 100% certified green energy; certificate details not independently audited in this batch.

Public-source research. Plans may change. See Evidence for sources and qualifications.