Community-scale geothermal networks could play a big role in Ontario’s transition to low-carbon energy

MaRS Discovery District unveils a road map to tap into the heat beneath our feet.

TORONTO, June 16, 2025 – As Ontario races to decarbonize its aging building stock while also meeting surging energy demands, MaRS Discovery District is unveiling a road map to 2050, which outlines an approach that could make our neighbourhoods less dependent on fossil fuels.

MaRS established the Road-Mapping Initiative for Networked Geothermal (RING) to bring together key stakeholders to explore the potential of decarbonizing heating and cooling in high-density Ontario cities through utility deployment of thermal energy networks (TENs).

TENs are shared networks of underground pipes that transfer heat in and out of buildings equipped with heat pumps. These systems could be installed at the neighbourhood level to provide an efficient, clean and resilient form of building heating and cooling, while also taking some of the pressure off the electric grid. The decarbonization of buildings will be essential for Ontario to achieve a low-carbon future.  Buildings are the third largest emitter of greenhouse gases (GHG) in Canada; it’s estimated that buildings account for approximately 18 percent of the country’s GHG  emissions, coming mostly from the use of gas for space and water heating. 

MaRS convened an 18-person working group of industry experts, who brought their expertise and diverse perspectives, drawing from the energy utility, construction, housing, government and non-governmental organization (NGO) communities. 

Based on insights and discussions, over the course of seven sessions from September 2024 to February 2025, the multi-stakeholder industry working group and MaRS identified six core recommendations that could enable strategic, coordinated and scaled implementation of utility TENs across Ontario. They include: 

1. Develop the ecosystem for utility TENs
2. Lead research and data collection
3. Enact policies and regulations 
4. Develop long-term utility TENs business model
5. Facilitate integrated planning 
6. Advance TENs technology 

“Ontario needs bold, systems-level solutions to meet its goals, and utility-scale TENs are an underexplored but highly promising tool. Our road map offers a pragmatic, collaborative pathway for unlocking this potential at scale.”
– Tyler Hamilton, Senior Director, Climate, MaRS

“As Canada undergoes a historic energy transition, the foresight to designate thermal energy networks (TENs) as critical energy infrastructure — with streamlined permitting and access to public financing — will be key to scaling this solution across Ontario. Informed by cross-sector input from nonprofit, public and private partners, this report offers the innovation and shared perspective needed to meet our collective sustainability challenges, while providing tools for organizations like ours to move toward decarbonizing the homes we steward in perpetuity. By planning today, we create the runway to embed utility-scale TENs as a core part of the energy transition and demonstrate what’s possible at the neighbourhood level.”
– Alia Abaya, CEO, Circle Community LandTrust

“Local governments — especially those with utility experience — have an outsized role to play in the energy transition. Utility-scale thermal energy networks must be planned hand-in-hand with community growth.”
– Matthew Day, Executive Director, WR Community Energy

“Thermal Energy Networks are a promising part of our decarbonization toolkit, with the potential to contribute to efficient, resilient energy systems at the neighbourhood scale, and to create good jobs in the process. The RING project is a model for how we might move these projects forward, using deeper collaboration with provincial decision-makers to support more effective planning, regulations and public investment.”
– Bryan Flannigan, Executive Director, Building Decarbonization Alliance 

The RING Report draws heavily from real-world precedents, such as the work of HEET, a U.S.–based, non-profit organization that works to cut carbon emissions through systems change and Eversource Energy’s networked geothermal pilot project in Framingham, Mass. The RING Report contextualizes the approach and solutions for Ontario and explains the urgency for work on utility-deployed TENs in the province. 

MaRS would like to thank the Grantham Foundation for the Protection of the Environment for its generous support of this work. We are also deeply grateful for the facilitation and in-depth advisory support of Audrey Schulman, executive director of the nonprofit climate-solutions incubator HEETlabs (a spin-off of the climate non-profit HEET). The RING Report was developed by the MaRS Climate team, as part of its Better Buildings program, which supports the scale-up of clean technologies for Canada’s built environment. 

Read the report
The full RING road map is available for download on the MaRS site: LINK

For more information or to schedule an interview, please contact:
media@marsdd.com

About MaRS
MaRS Discovery District is a charitable organization and North America’s largest urban innovation hub, dedicated to helping Canadian technology companies succeed. With a focus on climate, health sciences and other emerging technologies, MaRS supports startups tackling some of the world’s most pressing issues. MaRS spans more than 1.5 million square feet of cutting-edge office, lab, meeting and event space in downtown Toronto across two locations — the MaRS Centre and MaRS Waterfront. Since 2010, MaRS has helped ventures generate $11.5 billion in cumulative revenue, raise $19 billion in funding, and create and maintain more than 33,000 jobs. The MaRS platform also includes MaRS IAF, one of Canada’s top seed-stage venture funds. Through its world-class facilities, strategic programs and partnerships, MaRS accelerates the adoption of groundbreaking Canadian technology and bolsters a globally competitive innovation ecosystem.