More than 180 buildings in the core use an innovative system to deal with summer heat.
During the soupy summer months, one of the joys of being downtown is being able to duck into a building for some respite from the heat. The cool thing is, you have the depths of Lake Ontario to thank for that.
Much of the downtown core gets its chill on using a deep lake water cooling (DLWC) system that’s the largest in North America and is a critical part of the city’s goal to be net-zero by 2040.
More than 180 buildings in downtown Toronto—including parts of the University Health Network, City Hall, Scotiabank Arena, and Steam Whistle Brewery—are cooled by water from the cold temperatures of Lake Ontario.
Launched in 2004, the Deep Lake Water Cooling System, which is operated by Enwave Energy Corporation and the City of Toronto, has been using 4°C water from deep within the lake to do the job. The DLWC system works by pulling summertime heat out of buildings using a series of loops of mostly water that run under the downtown, and depositing that heat into the incoming cold water using heat exchangers.
According to Enwave’s website, the system can reduce electricity use by around 80 percent in the buildings it cools compared to a standard chiller plant. Since buildings generate over half of Toronto’s Greenhouse Gas (GHG) emissions, the City of Toronto says Enwave’s low-carbon cooling system is a crucial part of its net-zero plans. (And there’s more savings to come: Enwave is now going to be providing sustainable heat to downtown Toronto, too. Enwave broke ground this past May on a new low-carbon heating facility at their Pearl Street Energy Centre.)
So, the next time you seek relief from the heat in a downtown building, remember that chill is coming to you from 85 metres below the surface of Lake Ontario.