Japan / Facility

AirTrunk OSK1 Osaka West

Unknown MWTotal facility power not establishedSee capacity evidence for reported claims.

OSK1 · OSK1 西大阪 · ATOSK1 Project

Under Construction

AirTrunk hyperscale facility marketed as Osaka West, identified by municipal and property reporting at Nagasunishidori 1-chome, Amagasaki, Hyogo. Construction began in February 2024. The operator advertises 20+ MW total capacity without defining the power basis and still lists OSK1 as coming soon; actual opening is unconfirmed.

Last researched 2026-10-09Last verified Not independently verifiedPublished revision 1

No approved site photo yet. Photos and their source dates are published after evidence review.

Site profile

Operator: AirTrunk
Ownership: Unknown / not established
Business model / scale: Colocation / Hyperscale
Region / metro: Hyogo Prefecture / Osaka / Kansai
City / locality: Amagasaki
Address: 兵庫県尼崎市長洲西通一丁目35番 (parcel address)
Location: Parcel address corroborated by Amagasaki municipal disclosure and local property reporting; no independently sourced facility coordinates established.
Precision: unknown
Parent: Not assigned

Capacity evidence

Statements retain their dates, definitions and development scope. Do not add these rows together.

Claim / measurement	Scope and status	As of	Evidence and accounting
>20 MW Unspecified power	OSK1 ultimate scalable facility capacity Planned · cumulative	2023-10-17	Reported claim ↗ Excluded from capacity totals. Announcement date; says scalable to over 20 MW, without specifying IT, facility or grid basis. Establishes reported >5 MW scale, not live IT capacity.
20 MW Unspecified power	OSK1 facility under construction Under Construction · cumulative	2024-02-28	Reported claim ↗ Excluded from capacity totals. Groundbreaking announcement date. Body reports 20 MW; headline says 20+ MW. Power basis and phase allocation are unstated; overlaps other OSK1 claims.
20 MW Unspecified power	Existing OSK1 West Osaka facility Unknown · cumulative	2025-12-17	Reported claim ↗ Excluded from capacity totals. OSK2 announcement date; parenthetical OSK1 capacity is 20 MW. Existing does not explicitly mean operational. OSK2's explicit IT definition cannot be transferred to OSK1.
≥20 MW Unspecified power	OSK1 advertised total capacity Planned · cumulative	2026-10-09	Reported claim ↗ Excluded from capacity totals. Retrieval date of undated facility page, not publication or commissioning date. Literal 20+ MW represented conservatively as at least 20 MW; power basis remains unknown and timeline says coming soon.

Development timeline

2023-10-17 · announcement
OSK1 development announced
AirTrunk announced its first Osaka development and third Japan facility.
Supporting source ↗
2024-02-01 · actual_reported
Construction start reported
Local property report gives this construction-start date; operator separately confirmed commencement later that month.
Supporting source ↗
2024-02-28 · announcement_actual
Groundbreaking and construction commencement confirmed
Operator announced construction following a jichinsai ceremony.
Supporting source ↗
2024-12-23 · announcement_actual
AirTrunk corporate acquisition completed
Blackstone-led consortium and CPP Investments completed acquisition of AirTrunk; individual property ownership was not established.
Supporting source ↗
2026-02-02 · planned
Originally reported planned building completion
Date stated by March 2024 property reporting; no evidence found confirming completion or operational opening on this date.
Supporting source ↗

Disclosed specifications

Gross floor area

Approximately 16,500 m²

Operator marketing figure; local report gives 16,385.79 m², retained separately.

Source ↗

Technical data hall area

Over 5,400 m²

Operator-disclosed area.

Source ↗

Land area

5,324.05 m²

Local property reporting, not independently surveyed.

Source ↗

Building footprint

3,184.70 m²

Local property reporting.

Source ↗

Reported building floor area

16,385.79 m²

More precise local report differs slightly from operator's approximate gross floor area.

Source ↗

Building dimensions

6 above-ground floors; 41.2 m height

Local property reporting.

Source ↗

Power infrastructure

77 kV diverse high-voltage feeds

Voltage is not MW capacity or proof of energized service.

Source ↗

Substation

Dedicated onsite 77 kV substation

Disclosed as planned infrastructure in original announcement.

Source ↗

Connectivity

Carrier neutral; multiple entry paths

Named carriers and routes not disclosed in reviewed evidence.

Source ↗

Availability commitment

100% availability backed by SLAs

Advertised contractual commitment, not measured uptime.

Source ↗

Efficiency

Industry-low design PUE claimed

No numeric site PUE provided.

Source ↗

Renewable energy

Renewable sourcing options for customers

Design-stage offering; no OSK1 renewable share or executed supply arrangement established.

Source ↗

CASBEE disclosure

A; BEE 1.5

Applicant self-assessment published by municipality, explicitly not municipal certification.

Source ↗

Development applicant

OSK1特定目的会社

Municipal applicant identity does not by itself establish current property ownership.

Source ↗

Design and construction

Nikken Sekkei; Nishimatsu Construction, West Japan branch

Roles reported by local property source; both companies also appear in operator groundbreaking attendees.

Source ↗

Sources and references

Source attribution does not imply independent verification or permission to reuse images.

OSK1 Osaka West | AirTrunk ↗

Published Date unavailable · Retrieved 2026-10-09

Operator facility page identifies Osaka West, 20+ MW total capacity, approximately 16,500 m² gross floor area, over 5,400 m² technical halls, carrier neutrality and 77 kV diverse feeds.

AirTrunk expands in Japan with new data centre development in Osaka ↗

Published 2023-10-17 · Retrieved 2026-10-09

Announcement identifies OSK1 as AirTrunk's first Osaka development, scalable beyond 20 MW for large technology customers, with a dedicated onsite 77 kV substation and renewable sourcing options. Page also displays a later date of 19 December 2024.

AirTrunk breaks ground in Osaka ↗

Published 2024-02-28 · Retrieved 2026-10-09

Operator confirms construction commencement for OSK1; headline says 20+ MW while body says 20 MW. Facility serves large technology customers and complements Tokyo facilities.

令和5年度CASBEE届出建築物評価結果の公表 | 尼崎市 ↗

Published Date unavailable · Retrieved 2026-10-09

Municipal table lists ATOSK1 Project (data center), applicant OSK1特定目的会社, address 尼崎市長洲西通一丁目35番, and self-assessed CASBEE A, BEE 1.5. Page updated 26 November 2025; municipality explicitly says disclosure is not municipal certification.

【尼崎市】AirTrunk OSK1 データセンターの建設状況 2024年2月 | URBAN NOTES ↗

Published 2024-03-21 · Retrieved 2026-10-09

Local property report connects AirTrunk OSK1 to the same Amagasaki parcel and former Toyo Press site; reports six floors, 41.2 m height, 5,324.05 m² land, 16,385.79 m² floor area, construction starting 1 February 2024 and planned completion 2 February 2026.

Profile field evidence

Name: OSK1 Osaka West | AirTrunk; AirTrunk expands in Japan with new data centre development in Osaka

Aliases: AirTrunk expands in Japan with new data centre development in Osaka; 令和5年度CASBEE届出建築物評価結果の公表 | 尼崎市; 【尼崎市】AirTrunk OSK1 データセンターの建設状況 2024年2月 | URBAN NOTES

Kind: OSK1 Osaka West | AirTrunk; AirTrunk breaks ground in Osaka

Country: AirTrunk expands in Japan with new data centre development in Osaka; AirTrunk breaks ground in Osaka

Region: 【尼崎市】AirTrunk OSK1 データセンターの建設状況 2024年2月 | URBAN NOTES

City: 令和5年度CASBEE届出建築物評価結果の公表 | 尼崎市; 【尼崎市】AirTrunk OSK1 データセンターの建設状況 2024年2月 | URBAN NOTES

Metro: AirTrunk expands in Japan with new data centre development in Osaka; AirTrunk to build second Osaka hyperscale data centre to support AI growth

Address: 令和5年度CASBEE届出建築物評価結果の公表 | 尼崎市; 【尼崎市】AirTrunk OSK1 データセンターの建設状況 2024年2月 | URBAN NOTES

Operator: AirTrunk expands in Japan with new data centre development in Osaka; AirTrunk breaks ground in Osaka

Business Model: OSK1 Osaka West | AirTrunk; AirTrunk expands in Japan with new data centre development in Osaka

Scale: AirTrunk expands in Japan with new data centre development in Osaka; AirTrunk breaks ground in Osaka