Canada has an opportunity to produce 76 TWh of dispatchable renewable energy and decrease GHG emissions by 13 Mt every year, if it installs ground-source heat pumps in the 3.5 million new homes it has committed to build.
Canada's 15 million households have total floorspace of 2,190 million m2, an average 1,580 ft2 per household, according to NRCan data for 2020.
Each of these households consumes 26,500 kWh of energy every year, of which 21,700 kWh (82%) is thermal energy for space heating, water heating and space cooling; the balance is for lights and appliances.
These thermal end-use applications emit 3,300 kg of GHG per household each year, or 23 kg per square metre of floorspace, which is a national total of 49 billion kg (49 Mt) of GHG each year.
There is no question that a ground-source heat pump is the best option for producing thermal energy. Air-source heat pumps are more popular because they are less expensive to install and well-suited to renovations, but they are not as good as a ground-coupled unit in terms of performance, operating cost and environmental sustainability.
Most of the cost of a ground-source heat pump is the need to bury heat transfer loops in the ground which, in existing buildings, means heavy equipment must be brought onto site and mess the property. This major cost factor can be eliminated if the loops (horizontal or vertical) are installed at the same time as the house is constructed, when the grounds are messy and digging equipment is already on site.
Canada wants to build 3.5 million new homes, and if these new units were built with ground-coupled heat pumps as their source of thermal energy, they collectively would decrease GHG emissions by 13 billion kg and would produce 76 billion kWh of dispatchable renewable energy from the ground every year.
This solution requires government to commit to building new homes with the smallest impact on the environment and the lowest operating cost for future occupants.