In-Depth
These heat pumps may “invert” your thinking

September 4, 2024 – Heat pumps are increasingly popular because they offer significant energy savings compared to traditional home heating systems, such as an oil furnace or electric baseboard heat. Consider this energy efficiency comparison:

• Wood heating – 50%
• Heating oil systems – 60% to 85%
• Natural gas systems – 62% to 90%
• Electric heating systems (baseboards) – 100%
• Electric heating systems (heat pumps) – 190%

The latest advancements in HVAC technology are elevating heat pumps’ energy efficiency to even greater heights.

Halifax testbed

Halifax is located in HSPF (Heating Seasonal Performance Factor) Region IV. Its climate zone is characterized as “cold-humid”, which suggests cold, damp winters. This climatic region typically sees winter temperatures ranging from around -10 C to 0 C, but extremes do occur. Summer temperatures can vary, but they generally stay within 10 C to 28 C.

A test site in Halifax is trialling two heat pumps across two similar, occupied homes located on the same street. Both 5-bedroom, 4500-sf homes were built in 1991 using a combination of brick and vinyl siding for the building envelope—common materials that provide decent insulation against cold weather, but can vary in energy efficiency depending on the age and condition of the materials.

That is where the similarities end.

One home is testing a single-stage Daikin heat pump, while the other is trialling an advanced inverter Daikin FIT heat pump (photo). Both ducted systems boast a 16 SEER (Seasonal Energy Efficiency Rating), yet the inverter model is displaying notable energy savings.

The operational comparison conducted between these systems reveals that the inverter heat pump provides a 52% energy savings compared to the single-stage model. According to Daikin, inverter heat pumps generally offer 30-40% savings over non-inverter systems. The savings between the two test houses vary, depending on usage by each family. As a rule, factors such as home layout, age, and location can impact actual energy costs and savings.

Inverter heat pumps save energy

Inverter technology in heat pumps is often compared to cruise control in a car, designed to use power more efficiently and evenly while maintaining precise control.

An inverter is an intelligent compressor drive module that provides variable-speed operation. A single-stage unit operates at full capacity, turning on/off continuously to meet the temperature setpoint.

A two-stage unit using inverter technology, however, offers two levels of power to reduce the frequency of those on/off cycles. This minimizes energy spikes and temperature fluctuations, leading to faster achievement of set temperatures and, by extension, reduced energy use.

In fact, one of the most compelling advantages to inverter heat pumps is their reduced electricity consumption compared to traditional systems. In a typical operational scenario, a single-stage heat pump might consume around 12-15 kWh per day, while an inverter heat pump may only use 8-10 kWh for the same heating or cooling load.

Over a month, this difference of 30-40% can translate into substantial savings on your electricity bill.

Where inverter heat pumps thrive

Inverter heat pumps are not limited to single-family homes, as their versatility and use of ductwork makes them suitable for a range of applications, including managing the heating and cooling needs of multi-unit residences. Outdoor heat pump unit design is advancing alongside drive compressor technology, allowing for a slim build (36 x 31 x 13 in.) that fits well on decks and terraces.

And the solution is scalable, able to provide heating and cooling across multiple units.

Many facilities in the hospitality industry, including hotels, villas, and lodges, use these types of heat pumps to ensure consistent (and quieter) comfort for their guests. Whereas a traditional box-style outdoor condenser unit has a 78 dBA (e.g. vacuum cleaner), modern inverter heat pumps have a 56 dBA (e.g. household refrigerator).

Restaurants face unique challenges maintaining comfort, trying to balance the kitchen against varying occupancy levels in the dining area. An inverter heat pump can dynamically adjust to these disparities, ensuring that both locations are kept at optimal setpoints.

Inverter heat pumps integrate with existing ductwork to ensure consistent air quality and comfort throughout a home. Pairing these systems with smart thermostats to enable scheduling and location-based temperature control further enhances efficiency.

Is inverted the right choice?

Whether you’re thinking of getting your first heat pump, or upgrading your existing system, consider the upfront costs, long-term savings, and potential rebates or incentives. The cost will vary, based on factors such as home layout, age, and location.

Due to their advanced energy efficiency, inverter heat pumps typically have a higher upfront cost compared to single-stage systems, but the extra energy savings offset the higher price tag.

Additionally, rebates from various governments and utilities help reduce the initial installation cost.

The federal Oil to Heat Pump Affordability Program (O2HPAP) program, for example, provides financial incentives to help homeowners transition from oil-based heating systems to electric heat pumps. The rebates can significantly lower the upfront installation costs.

Heat pumps have already shown they provide significant energy savings compared to other heating systems, with advanced inverter units showing they can “ratchet up” those savings even more.

For more advice, contact your trusted HVAC professional to discuss the best heat pump solution for your home or business.

Kelsey Young serves as sales manager with EMCO HVAC. Founded as the Empire Manufacturing Co. Ltd. in London, Ont., in 1906, EMCO Corp. is one of Canada’s largest integrated distributors of plumbing, waterworks, industrial, and HVAC products for the construction industry.