What public transit is to moving people, district energy is to heating and cooling buildings.
Public Works looks at public space, urban design, and city-building innovations from around the world, and considers what Toronto might learn from them.
What do a public library, a YMCA, and a multi-tower condominium have in common?
All of these buildings are located in the City of Markham and share an innovative approach to local energy.
Markham is home to two district energy systems that meet the heating and cooling needs of buildings, such as the Markham Stouffville Hospital and the Markham Pan Am Centre. District energy is an energy distribution system that serves multiple buildings in a neighbourhood. Typically, hot and cold water are produced at a central location and pumped through nearby buildings. In Markham, 48.5 kilometers of piping service more than 800,000 square metres of commercial, residential, and recreational space.
In 2014, the energy saved by Markham’s district energy systems was equivalent to the natural gas consumption of 2,266 homes.
District energy also makes financial sense. It costs 15 per cent less than traditional systems and contributes to local economic development: money spent on utilities stays in the community to support the operation and maintenance of neighbourhood heating and cooling systems.
It is not yet a household name, like solar panels or wind turbines, but district energy has a long history in Toronto. The University of Toronto’s St. George campus has used district energy for more than 100 years. Off campus, Enwave Energy first started providing centralized heating services to buildings in downtown Toronto in the 1970s. In 2004, the company introduced new technology that uses lake water to provide cooling during the summer months.
Fernando Carou, a senior engineer at the City of Toronto who oversees community energy planning and new district energy systems, explains that there are five large district energy systems in the city. They serve areas such as Exhibition Place and York University’s Keele Campus, as well as several smaller systems at places like Ryerson University and the Centre for Addiction and Mental Health.
“The opportunity for district energy in the city is very significant,” Carou says. He estimates that Toronto has the density to support about 30 district energy systems.
The next challenge, however, for district energy is expanding beyond health and educational campuses into commercial contexts and tapping into Toronto’s hot real estate market.
The installation of district energy in Regent Park hints at the future of community energy in Toronto. District energy has been built into the revitalization of Regent Park since the outset. Although you can’t notice it from the sidewalk, the central energy plant for the neighbourhood is located in the basement of 252 Sackville Street, and has been in operation since 2009.
District energy works well in the context of a multiphase project like Regent Park because, in Carou’s words, “the value of district energy is in the network.” As construction continues, more buildings are connected to the central heating and cooling facilities. Eventually, more than 50 buildings spread over 69 acres will share the same system.
The gradual growth of a network of buildings allows for improved sustainability over time. “You can bring in more costly technology as the network grows,” Carou explains. District energy systems typically start with a conventional natural gas boiler and electric chiller, but, as more buildings receive online savings, economies of scale enable investment in renewable sources such as geothermal or solar energy.
Natural Resources Canada estimates that in Regent Park, the use of district energy in the first phase alone reduced greenhouse gas emissions by 8,000 tonnes per year. Over a 30-year period, energy savings are expected to be the equivalent of taking 66,000 cars off the road for a year.
In fact, there are other similarities between district energy and public transportation. While both require substantial upfront investment, they offer long-term cost savings and emissions reductions. According to the City of Toronto’s 2013 Greenhouse Gas Inventory [PDF], transportation is the source of 41 per cent of emissions in Toronto; another 48 per cent of emissions come from buildings.
A sustainable city requires dense networks of both public transit routes and district energy systems. Markham boasts the first residential condominium connected to a district energy system in Canada and Regent Park proves that the model is transferrable to Toronto. Now it’s up to other developers in the residential and commercial sectors to collaborate, connect buildings, and realize the cost savings offered by district energy.