Heat pumps were on my list of potential topics and the recent announcement of a Clean Home Heating Initiative by the Minister of Energy Todd Smith prompted me to write about them now.
A heat pump both heats and cools your home (or business) using electricity to transfer energy between your home and another location. These locations can either be the ambient air outside your home (air sourced heat pumps) or the ground (geothermal heat pumps). For the purposes of this blog, I will focus on air-sourced heat pumps but the same principles work for geothermal or ground sourced heat pumps.
During the winter, the heat pump takes energy from the outside air and pumps it into your home thereby heating it. Even on very cold Canadian winter nights there is still energy in the outside air to allow for this to happen. However, to be safe a back-up electric heater is not a bad idea. Likewise, during the summer the energy in air in your home is extracted and pumped outside; cooling your home. For a comprehensive explanation of how heat pumps work please see this website: https://www.nrcan.gc.ca/energy-efficiency/energy-star-canada/about/energy-star-announcements/publications/heating-and-cooling-heat-pump/6817
Advantages of heat pumps include:
- A heat pump both heats your home in the winter and cools it in the summer. You therefore do not need to have both an air conditioner and a furnace; the heat pump replaces both. One less device is always a good thing.
- A heat pump is much more energy efficient than a furnace and has about the same efficiency as an air-conditioner. Estimates are that a heat pump is as much as three times more efficient than a furnace.
- A heat pump does not require carbon-based fuels to operate (more below).
- A heat pump is not as dry as heat from a furnace. It is circulating the outside air which is naturally more humid. This may reduce the need for a dehumidifier.
Disadvantages of heat pumps include:
- They are more expensive to install than a furnace and air conditioner. I cannot really put a number on this as the costs of all the units will vary by house and location.
- The do not last as long as a furnace and air-conditioner. A heat unit lasts 10-15 years compared to 20-30 years for furnaces and air-conditioners. In both cases this naturally depends on the quality of the units installed and their use. My builder-supplied furnace at my previous house only lasted 10 years.
The question that is hard to answer is which is more cost effective. This will depend on the particulars of your residence and the estimates for the relative costs of fuels and electricity going forward. Right now, fuels are rather expensive (thanks Putin) and electricity is subsidized (thanks Doug) so heat pumps might seem attractive. As for installation, whether a new build or not, the ease of retrofitting and the age and condition of the existing furnace and air-conditioner will all be a factor. Cost effectiveness may not be the only reason for one to consider using heat pumps over conventional heating systems.
The primary reason for this Clean Home Heating Initiative and previous federal government programs is to provide an upfront rebate to move the needle on this cost/benefit analysis in favour of heat pumps in an effort to reduce greenhouse gas production.
Heating and industrial use accounted for 38% of energy use in Ontario in 2016 according to the Environmental Commissioner of Ontario. This is equivalent to transportation which accounts for 39%. The remaining 23% is electricity which is now 90% carbon free. The electrification of transportation currently dominates the news in this regard due to the enormous investments and amazing developments in electric vehicles of all sorts. The electrification of heating will be equally important if we are to meet climate reduction goals. Heat pumps are viewed as key product for this to happen.
I do have some personal experience with heat pumps. I had them installed in a new building I was erecting further north in 2021. This would be further north where they have real winter; not the banana belt weather of Niagara. The heat pumps have been in place over a year and work very well. Once I back out the exorbitant Hydro One delivery charges, the costs are not that bad.
I did have an unplanned demonstration of how well they work. With their “smart” technology I am able to monitor and program the thermostat remotely. Last winter was unusually cold and one rather cold morning I noticed the actual temperature was well below the setting. As the day progressed the building did heat up again. The contractor checked it out and it turned out the back-up electric heater had not been installed properly so never turned on. The heat pump worked well enough so nothing froze but still needs some support in very cold weather. There is also the issue of whether a back-up generator will be needed in case the power goes out; this would apply to conventional heating systems as well.
According to the Government of Canada, over 700,000 heat pumps have been installed in Canada. I have also seen heat pumps promoted by a number of conservation and climate concern organizations. I would say that they are not yet mainstream, and the technology is still a little too uncertain for many, but heat pumps do have the potential as part of the long-term solution to decarbonize heating in Canada.
1 thought on “Heat Pump Blog”
Thanks for sharing, air source heat pumps are a popular and effective way to heat and cool a home because they use less energy, flexible, and easy to install and keep up. But when choosing an ASHP system for a certain application, it’s important to think about things like the climate, the size of the building, and the budget.