Transparency Around Ontario Data Centre Development

An independent public resource.

An independent, sourced resource tracking publicly known data centre developments across Ontario, including approvals, infrastructure considerations, regulatory frameworks, and industry trends.

Rapid Expansion
$19B announced Canadian investment in AI and cloud infrastructure (Microsoft)
Growing Electricity Demand
Data centres are projected to account for 13% of Ontario's new electricity demand by 2035 (provincial estimate)
Limited Public Disclosure
Ontario does not require standardized public reporting for data centre operators
No Centralized Tracking
There is no single public database consolidating publicly available data centre developments, approvals, and locations
Bill 40 Public consultation on grid connection regulations closed November 4, 2025. Regulations defining approval criteria, community obligations, and reporting requirements have not been published yet — stay tuned for more updates.
01 — The Map

Data centres across Ontario

Operational, under construction, and publicly disclosed facilities. Each entry is based on publicly available sources including ERO filings, municipal planning documents where available, and corporate or government announcements.

Legend
Operational
Under construction
Approved
Proposed / announced
Loading… Database actively expanding.
Last updated May 2026.

Is something missing? If you know of a data centre in Ontario not listed here — proposed, approved, or operational — we want to hear from you.

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Not all data centres are the same

When a new data centre is announced in Ontario, the public conversation often treats all facilities as interchangeable. They are not. A carrier hotel in downtown Toronto, a colocation campus in Markham, and a hyperscale AI facility in Vaughan have fundamentally different footprints — in electricity consumed, water drawn, and noise produced for surrounding communities.

Type 01

Carrier Hotels

Buildings where dozens of telecom companies, ISPs, and internet exchanges physically connect to each other. The value is who else is in the building, not the facility itself. Multiple independent operators can share the same address.

Power draw is moderate (5–20 MW), distributed across many small tenants. Most are air-cooled. External noise impact is relatively low. 151 Front Street West was purpose-built in 1954 as a telecommunications hub — not a conversion from another use.

Ontario examples: 151 Front Street West, Toronto (operators including Equinix TR1, Cologix TOR1, Telehouse Canada, Amanah, 3Z Canada — all in the same building). TorIX operates at multiple locations including 151 Front, 45 Parliament Street, and 905 King Street West.
Type 02

Colocation Facilities

The operator provides the physical infrastructure — building, power, cooling, security — and tenants bring their own servers. The operator does not control or know what runs on tenant equipment. This is the most common model in Ontario.

Purpose-built campuses typically draw 10–50 MW. Newer facilities achieve better energy efficiency. Cooling varies: some use chilled water systems (higher water use), others are air-cooled. Generator testing noise affects neighbours weekly or monthly.

Ontario examples: Cologix TOR4 (Markham), Csquare YYZ1 & YYZ2, Digital Realty TOR1 (Vaughan), Halton Data Center (Milton)
Type 03

Hyperscale Facilities

Built by a single company exclusively for its own use — Microsoft, Amazon, Google, Meta. Not open to other tenants. These generate the most significant public infrastructure discussions in Ontario.

A single campus can draw 100–500+ MW (equivalent to tens of thousands of homes). AI workloads produce extreme heat, requiring liquid or evaporative cooling that can consume millions of litres of water annually. Largest noise footprint of any type.

Ontario examples: Microsoft YTO 11 (Vaughan, under construction). AWS, Google and others have confirmed Ontario presence but have not publicly identified specific facility locations.
Type 04

Data Centre-Ready Developments

Industrial or commercial properties built or retrofitted to the structural and electrical specifications a data centre requires, but not yet occupied by a data centre operator. A newer category emerging across the GTA.

The actual energy, water, and noise profile of these sites is entirely unknown until a tenant is confirmed and a facility type is known. “Data centre power procurement underway” is a signal that a tenant may already be committed.

Ontario examples: Prologis Meadowvale Hustler Park (Mississauga, available June 2027), Prologis Steeles Avenue Park (Brampton, available July 2027)

Environmental and community impact by type

Electricity consumption

Hyperscale (AI/cloud)Very High
Purpose-built colocationHigh
Carrier hotelModerate
DC-ready developmentUnknown

Measured by PUE (Power Usage Effectiveness). Modern hyperscale achieves 1.1–1.2; older facilities can reach 2.0+. Ontario does not require operators to report PUE publicly.

💧

Water consumption

Hyperscale (liquid-cooled)Very High
Chilled-water colocationModerate
Air-cooled colocationLow
Carrier hotelMinimal

Driven by cooling technology, not facility type alone. AI chip density is the key variable. Ontario does not require water consumption reporting. Microsoft's YTO 11 voluntary disclosure is the exception, not the norm.

🔊

Noise impact

Hyperscale (suburban)Very High
Purpose-built colocationHigh
Carrier hotel (urban)Low
DC-ready developmentUnknown

Sources: cooling towers (continuous), backup generators (weekly testing, 85–100 dB at source). Municipal noise by-laws apply but continuous low-frequency industrial noise is difficult to enforce.

What operators disclose — and what they don’t

Information Availability Notes
Power capacity (MW) Typically public Operators usually publish maximum capacity in marketing materials
PUE (energy efficiency) Sometimes public Published by some operators in sustainability reports, usually at company or regional level — rarely per building
Actual electricity consumption Not public No Ontario requirement to report. IESO tracks large customers but does not publish by facility name
WUE / water consumption Almost never public Microsoft's YTO 11 voluntary estimate is a rare exception. No Ontario reporting requirement exists
Cooling technology type Sometimes public Larger operators often reference air vs. water cooling in spec sheets or sustainability reports
Certifications (LEED, ISO, Uptime) Typically public Operators market certifications; independently verifiable through certifying bodies
Carbon emissions Rarely public Some large operators publish Scope 1/2/3 at corporate level. Per-facility figures are almost never disclosed in Ontario
Noise assessments Sometimes public May appear in municipal planning filings or environmental assessments if required. Not consistently available

This tracker cites figures where operators have voluntarily disclosed them, and clearly states when information is not publicly available. The goal is not to fill gaps with estimates but to make the gaps themselves visible. Residents, municipalities, and policymakers deserve to know what they are — and are not — being told. Read the full explainer in Updates →

03 — Regulatory Tracker

The regulatory landscape

What legislation exists, what it does and does not do, and where the accountability gaps are. Updated as regulations are published.

Pending Regulation

Bill 40 — Electricity Act Amendments

Bill 40 amends the Electricity Act, 1998 and related statutes to introduce new rules governing how large electricity load facilities, including data centres, connect to Ontario's electricity grid.

The legislation enables the Minister and the Ontario Energy Board, through regulation, to establish connection requirements and approval processes for specified load facilities above defined demand thresholds (including thresholds that may be set in regulation).

It also expands the objectives of Ontario's electricity system to explicitly include economic growth and allows those objectives to be considered in connection and transmission decisions.

The framework gives government and regulators discretion to define criteria for connection approval, including facility type, electricity demand, geographic factors, and required conditions for grid access.

This is a grid connection and system planning mechanism that operates alongside Ontario's existing regulatory framework. It does not, within the Act itself, introduce new reporting or disclosure obligations for data centre operators; however, further requirements may be established through regulation.

The consultation process for the proposed framework concluded in late 2025, and implementing regulations have not yet been published as of this update.

Source: Electricity Act, 1998 (as amended by Bill 40, SO 2025, c.22) · Ontario Legislative Assembly

Scope of the Consultation

What the Bill 40 consultation addressed

The Bill 40 consultation focused on matters related to electricity grid connection for large load facilities, including connection size thresholds, geographic considerations, system cost allocation, and criteria related to economic development and grid access.

These questions primarily relate to how and under what conditions facilities are permitted to connect to Ontario's electricity grid.

The consultation was not structured as a comprehensive review of long-term post-connection reporting, environmental disclosure frameworks, or ongoing operational transparency requirements.

At this stage, the legislation and accompanying framework do not include new mandatory reporting requirements for data centres once operational.

Current Regulatory Landscape

What exists and what is not standardized

Exists: Voluntary disclosures by some operators relating to energy use, cooling systems, and community investment. Where available, these are referenced in individual facility profiles and attributed to public statements or filings.

Not standardized province-wide:

  • A centralized public registry of approved or proposed data centre developments
  • Mandatory reporting of energy or water consumption by data centre operators
  • Uniform environmental or operational disclosure requirements across facilities
  • A single mechanism for public tracking of operator commitments after grid connection

Pending: Regulations under Bill 40 that will define the ministerial approval and grid connection framework for specified load facilities, including eligibility criteria, approval processes, and conditions for connection. These details have not yet been finalized.

Section 04 — Key Questions

Questions about Ontario's data centre and energy system

These questions identify areas where public information is incomplete or evolving. This section is updated as new information becomes available.

05 — Updates & Analysis

Latest updates

Regulatory developments, facility announcements, best practices from other jurisdictions, and community impact reporting. Updated as news develops.

06 — Plain Language Definitions

Plain Language Definitions

Simple explanations of key terms used in discussions about Ontario data centres, AI infrastructure, and electricity planning.

What is a Data Centre?
🖥️Data centre
A large building filled with computers that store data, run applications, and support services like cloud computing and artificial intelligence. They require significant electricity and cooling infrastructure.
🏗️Hyperscale data centre
A very large data centre built by a major technology company for its own use. These facilities operate at massive scale and require significant electricity, water, and infrastructure investment.
☁️Cloud computing
Using computing services like storage, software, and processing over the internet instead of on a personal device or local server. Data centres are the physical infrastructure that makes cloud computing possible.
🤖AI compute
The computing power needed to build and run artificial intelligence systems. AI applications place significant demand on data centre infrastructure, driving much of the current expansion in Ontario.
AI Basics
🏋️Training vs. inference
Training is when an AI system is built using large amounts of data — computationally intensive and high energy. Inference is when the trained AI responds to questions or performs tasks. Inference uses less energy per request but happens far more often, and at scale can exceed training demand.
Electricity System
🔌Electricity grid
The network that delivers electricity across Ontario from power plants to homes and businesses. Large data centres place significant new demand on the grid and may require infrastructure upgrades to connect.
📊Electricity demand (load)
The total amount of electricity being used at a given time. Large data centres can significantly increase local and provincial demand. Ontario projects data centres will represent 13% of new electricity demand by 2035.
🔗Grid connection
Approval required for a facility to connect to Ontario's electricity system and begin drawing power. Under Bill 40, large facilities may require ministerial approval before connecting.
Megawatt (MW)
A unit of electricity demand. One megawatt is roughly equivalent to the power used by about 1,000 homes. Large data centres can draw 50 to 100 megawatts or more.
🔀Transmission vs. distribution
Transmission refers to high-voltage lines that move electricity across long distances. Distribution refers to the local lines that deliver electricity to homes and businesses. Data centres typically connect at the transmission level.
Planning & Development
📍Zoning
Municipal rules that determine what types of buildings or uses are allowed on a piece of land. Data centres require appropriate zoning approval from the local municipality before construction can begin.
🏢Site plan approval
A municipal review process that determines how a building is designed and built on a site, including access, landscaping, and servicing. A step in local planning approval for data centre development.
🧭Infrastructure load
The total demand a development places on systems like electricity, water, and transportation. Data centres place concentrated infrastructure load that communities and utilities must plan for.
Water & Environment
💧Direct vs. indirect water use
Direct water use is what a data centre uses on-site for cooling. Indirect water use is consumed at the power plants generating the facility's electricity. Operators typically report direct consumption only. Researchers note indirect consumption can be significantly higher at scale.
🌿Environmental Registry of Ontario (ERO)
A public website where proposed government policies and regulations are posted for public comment. ERO postings are a primary source for tracking data centre-related regulatory activity in Ontario.
Policy & Regulation
📜Legislation vs. regulation
Legislation refers to laws passed by government, such as Bill 40. Regulations are the detailed rules that explain how those laws are applied in practice. Regulations are created after legislation passes and fill in the operational details.
🔑Ministerial approval
Under proposed Bill 40 amendments, the Minister of Energy and Mines would approve or reject grid connection requests from qualifying data centres. This is a grid access decision and does not impose ongoing reporting or conduct obligations once a facility is connected.
🌐Data sovereignty
The principle that data is subject to the laws of the country where it is stored. Building Canadian data centre capacity means Canadian data stays in Canada, subject to Canadian privacy law, rather than being stored on foreign infrastructure.

Submit a tip or correction

This tracker is only as accurate and complete as the information available to us. We actively welcome tips, corrections, source documents, and facility information from residents, municipal staff, journalists, and industry insiders.

All submissions are reviewed before being incorporated. Sources are attributed where permitted, or kept confidential on request.

A data centre not listed on the map
A factual error in a facility profile
A regulatory update or new ERO filing
A public commitment not reflected here
Community impact information we should know about

Submissions go directly to our editorial inbox at ontariodatacentres@gmail.com. We do not share your contact information. Anonymous submissions are welcome.