Can a heat pump replace an air conditioner and furnace in Alberta?
A “fantastic technology” that might need a little help on the prairies
Air conditioners were one of the hottest renovation requests in the summer of 2021, largely thanks to temperatures in western Canada hitting what CTV Edmonton’s chief meteorologist did Josh Classen (Radio und Fernsehen ’96) called “historic” heights.
The recent device shortage undoubtedly struck many sweaty customers as completely uncool.
It could also have led them to explore alternatives other than kiddy pools and cold drinks. The Canadian government wants energy-efficient heat pumps to be high on the list of long-term cooling solutions – and that we also use them for heating. To that end, she has qualified them for discounts under her Canada Greener Homes Grant program.
When it comes to air conditioning, heat pumps are undoubtedly the greener and lower carbon option. But if recommended for dual service to replace conventional heating systems as well, some parts of Canada could get them cold. Do you have a place in the prairies and northern Canada where the thought of a broken stove is a midwinter nightmare?
We asked Adam Budde (Sheet Metal Worker ’09, Refrigeration and Air Conditioning Mechanic ’15) – a project appraiser with Edmonton HVAC specialist, Vets Group – to clear the air on this hot topic.
This is how heat pumps work
Heat pumps cool or heat with an indoor and an outdoor unit as required. “In cooling mode, it extracts heat from the room air and transfers it to the outdoor unit,” explains Budde. “In heating mode, it reverses and extracts heat from the outside air and releases it inside.”
Air temperatures change the physical phase of a refrigerant in the equipment (from vapor to liquid or vice versa), thereby releasing or consuming energy. This gain or loss of energy then changes the temperature of a medium that travels through pipes to heat or cool a room.
What they cost
Compared to a conventional air conditioning system, you have to pay two to three times more for the installation, says Budde. You’ll save on the cost of natural gas that heat pumps don’t use, but you’ll instead pay attention to the price of electricity, which tends to be the more expensive option in Alberta.
Why heat pumps consume less electricity than air conditioning
Air conditioners use a lot of electricity. In fact, due to climate change, some researchers are directly linking the need for expanded power grids in the US to the need for cooling.
With heat pumps, the relative efficiency comes from a so-called power control, says Budde. An air conditioner or stove is instructed by a thermostat to either turn itself on or off – an all-or-nothing binary. A heat pump, on the other hand, runs on a slope and increases its energy requirement in stages, just enough to meet the demand.
“They only work as much as necessary,” says Budde, “so that they use less energy when demand is lower.”
How they perform in Alberta
Heat pumps cool a room just like air conditioning. However, the further north you go, and the more consecutive days you can bring below -20 ° C, can test your ability to comfortably heat a house.
Heat can be obtained from -20 ° C air, explains Budde, but getting enough means getting more air through the heat pump. In addition, he adds, cold air is denser and puts a heavier load on the machine. In the best case scenario, the pump will use more energy and become less efficient. In the worst case, it will be difficult for him to keep up.
There are hybrid models that combine a heat pump with natural gas-powered heating technology, emphasizes Budde. Otherwise, he admits that his professional background urges him to couple a heat pump with a gas-powered backup oven – “to be on the safe side”.
How to improve your carbon footprint
When looking at the environmental impact of heat pumps in Alberta, Budde looks at what he calls “personal carbon footprint”.
On site, they help to reduce the energy required for cooling. However, Budde points out that most places in the province are linked, albeit indirectly, to greenhouse gas emissions, as 91% of Alberta’s electricity is generated from fossil fuel burning. Given our infrastructure, it takes a lot of footprints to march towards sustainability while enjoying the luxury of a cool home on our hottest summer days.
Even so, Budde doesn’t rule out heat pumps as part of a healthy energy-saving mix at home, even in a city as cool as Edmonton. Although it is not one of the warmest cities in Canada, it is one of the sunniest with an average of 325 bright days per year.
“Heat pumps are a fantastic technology,” he says. “If you can provide your house with solar energy and operate your own electricity grid, that’s child’s play for me.”
AAAAND … there is the record. With temperatures climbing over 30 this afternoon, Edmonton is breaking the 1961 mark and this is now officially the longest stretch of 30-degree days the city has ever seen. #yeg #yegwx pic.twitter.com/yTwtXs7YkV
– Josh Classen (@joshclassenCTV) July 2, 2021
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