Across Canada, the number of days that buildings of all sorts require heating far outnumbers those that require cooling.
According to data gathered by James Cotton, professor in the Department of Mechanical Engineering at McMaster University and associate director of the McMaster Institute of Energy Studies, the ratio in Toronto, for example, is about seven to one. Heating requires energy, which in turns creates carbons. A number of projects and initiatives are seeking alternatives that capture, store and reuse what is called “waste heat.”
Cotton and fellow researchers from McMaster and Ottawa universities have developed what they call the Integrated Community Energy and Harvesting System, or ICE-Harvest, “a grid modernization solution for cold climates that incites a paradigm shift in virtual power plant design and operation.”
The ICE-Harvest strategy results in as much as 50 per cent of all building heating loads being met by energy that is currently rejected into the atmosphere and instead is stored as residual energy for later use, daily and seasonally.
Canada is not alone investigating this concept.
Australian studies suggest as much as 80 per cent of the heat lost through manufacturing processes can be recovered cost effectively.
“This means waste heat recovery is increasingly recognized as a key opportunity for businesses to improve their bottom line while reducing carbon emissions,” says the Australian Department of Climate Change, Energy, the Environment and Water.
Other reported initiatives in heat capture and recycling are quite innovative.
Three Pizza-Pizza outlets in the Toronto-Hamilton area have installed the POWER (Pizza Oven Waste Energy Recovery) system, developed through a five-year research partnership program with McMaster University. Repurposed waste heat from pizza ovens is used to offset heating needs within the restaurant.
An arts venue and dance club in Glasgow, Scotland, captures the body heat released on its dancefloor. The heat is converted into thermal energy and stored in specialized bore holes that funnel it back to the club when needed.
“If you’ve got a big DJ, absolutely slamming basslines and making everyone jump up and down, you could be generating 500-600W of thermal energy,” David Townsend, founder of geothermal energy consultancy TownRock Energy that designed the Bodyheat system, told the BBC.
One of Canada’s most ambitious projects for heat recovery, storage and reuse is in the False Creek area of Vancouver.
The Neighbourhood Energy Utility (NEU) has grown significantly since opening in 2010 and now supplies low carbon energy for heating and hot water to 6.4 million square feet of mixed-use buildings, including Science World and Emily Carr University.
“A significant portion of the NEU’s renewable energy supply comes from sewage heat recovery, where the latent heat from sewage is captured using a heat pump process at the False Creek Energy Centre, located under the Cambie Bridge,” says the City of Vancouver.
An additional 6.6 megawatts of sewage heat recovery equipment is set to be installed in the near future.
Across the river from Québec City in Sainte-Foy, the Albédo, a retrofitted 12-storey building that includes 128 senior housing units and a 150-space day care, will use the recovered thermal energy from the Intact Assurance Ice Centre located next door.
The ice facility has a large refrigeration system that keeps its five rinks frozen. However, much of the heat generated is lost to the outdoors. As a result of an agreement between the City of Québec and Action-Habitation, a geothermal system will capture that heat and provide heating and cooling for the Albédo. As reported by local media, the production of hot water using a heat pump will step in when there is heat recovery at the sports complex or when the Albédo is in air conditioning mode.
The harvesting of waste heat and thermal storage can be a cornerstone of any heating decarbonization strategy, write Cotton and his researchers.
“This local energy source can displace additional centralized electrical generation and the associated grid infrastructure investments.”
In turn, it can create what one Albédo project engineer calls “a virtuous circle.”
John Bleasby is a Coldwater, Ont.-based freelance writer. Send comments and Inside Innovation column ideas to firstname.lastname@example.org.