Ottawa is home to a growing number of data centres — and a McMaster University professor says the enormous heat they generate could be captured and redirected to warm homes and businesses, rather than being released as waste into the atmosphere.
As communities across Ontario, including Hamilton, grapple with a surge in data centre development, Prof. James Cotton of McMaster University is drawing attention to an underutilized opportunity: waste heat recovery.
What Is Waste Heat Recovery?
Data centres consume massive amounts of electricity to power and cool their servers. That cooling process generates significant heat — heat that is typically expelled into the surrounding environment with no secondary use.
Cotton argues that if properly managed, this thermal energy could be captured through district heating systems and piped into nearby residential and commercial buildings. The concept isn't new — it's been deployed with success in cities across Scandinavia and parts of Europe — but uptake in Canada has been slow.
"Heat is a resource," Cotton has said. "We shouldn't be thinking of it as a byproduct to get rid of."
Why Ottawa Should Be Paying Attention
Ottawa's tech sector has expanded steadily over the past decade, and with that growth has come increased demand for data infrastructure. Federal government facilities, cloud providers, and private enterprises all operate server infrastructure in and around the city.
At the same time, Ottawa residents face rising home heating costs, and the city has committed to ambitious climate targets as part of its official plan. District energy systems powered by recovered heat could help address both concerns simultaneously.
The City of Ottawa already operates a district energy network in parts of the downtown core and has explored expanded geothermal and low-carbon heating options. Integrating waste heat from data centres into that grid is a logical next step — one that cities like Stockholm and Paris have already embraced.
The Challenges Ahead
Cotton acknowledges that implementation is complex. Data centres and residential areas aren't always geographically close, and building the necessary heat exchange infrastructure requires upfront capital investment and coordination between private operators and municipal governments.
Regulatory frameworks also haven't kept pace with the technology. In Ontario, there's currently no requirement for data centre developers to consider waste heat as part of their environmental assessments or building approvals — something Cotton and other researchers believe should change.
Hamilton is among the Ontario cities actively wrestling with how to manage a wave of proposed data centre projects, raising community concerns about energy consumption, noise, and land use. The waste heat conversation is emerging as one potential lever to make these facilities more palatable — and more useful — to host communities.
A Timely Conversation for Ottawa
As Ottawa continues to attract tech investment and federal digital infrastructure, city planners and councillors would do well to examine what a local waste heat recovery strategy could look like. The technology exists. The need is clear. What's missing is policy will and public pressure.
Professor Cotton's work is a reminder that with the right framework, a liability — industrial heat — can become a community asset.
Source: CBC News Hamilton
