Power Before Land: Securing Utility Capacity for an Ontario Data Centre
The site is the connection
A data centre is a load first and a building second. The parcel that looks right on a map, with good highway access and county land prices, is worthless for this use if the local distribution company cannot deliver the megawatts on a timeline the project can survive. So the site search starts at the substation, not at the listing.
The question to put to the utility before anything else is simple: how much firm capacity is available at this location today, how much more could be made available, by when, and at whose cost. The answer sorts candidate sites faster than any other factor.
Distribution or transmission
Smaller facilities connect to the local distribution system, which is the network that serves the surrounding industrial park. Capacity there is finite and often already allocated to other customers, so a modest facility can still exhaust what is available. Larger facilities connect at transmission voltage, which usually means a dedicated substation or a customer-owned transformer station and a direct relationship with the transmission operator as well as the local utility.
The threshold between the two is not a fixed number. It depends on what the local feeders can carry and what is already committed. The utility will tell you which side of the line a proposed load falls on, and that determines the approvals path, the equipment the owner has to fund, and the schedule.
How the assessment runs
A formal connection request triggers an engineering assessment of what the proposed load does to the network: whether existing feeders and stations can carry it, what upgrades are needed and how the cost of those upgrades is shared. The assessment is not a formality. Its findings decide the connection cost and the earliest date the load can be energised, and both belong in the feasibility model before land is committed.
Large loads may also require a system-level study by the provincial system operator, because a new load of that size affects the regional supply picture, not just the local wires.
What sets the timeline
The building is rarely the long item. Where the connection needs a new feeder, a station expansion or a new transformer station, the utility work is measured in years, and long-lead electrical equipment such as large transformers has its own procurement timeline that the owner does not control. The utility timeline, not the construction timeline, is the critical path on most Ontario data centre projects, and it should be treated as such from the first schedule.
On-site generation
Generators are part of every tier topology as backup, and some owners look to on-site generation to bridge or replace an inadequate grid connection. It can do the first. It rarely does the second economically at scale, and it changes the approvals: air emissions approvals, fuel storage, noise and the environmental compliance approval process all come into play, and the neighbours notice. Generation can buy time on the utility schedule. It seldom removes the need for the connection.
Fibre and water
Two further checks belong at site selection. Fibre: at least two physically diverse routes to the parcel, from more than one carrier, entering the building at separate points. Water: whether the cooling design needs a municipal supply and what the municipality can allocate, or whether the design should assume closed-loop or air-cooled plant from the start. Both are easier to settle before the land is bought than after.
Our sequence
We put the utility conversation first, then fibre and water, then zoning and servicing, and only then the offer on the land. On the sites we have taken from raw land through servicing, the same discipline applied: confirm what can be delivered to the parcel before committing to it, carry the utility and municipal approvals as one track with milestones, and design the yard, the generator positions and the service entrances with the utility so the building is not redrawn when the connection design lands.
Talk to the Terrahills Team
Ready to apply these principles to your next Ontario project? Our team has direct experience across commercial, industrial, infrastructure, and multi-residential construction.
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