A right-sized electric heat pump—and a good installation—will not only keep homeowners warm at night, but deliver many years of reliable service, comfort, and energy and cost savings, while reducing carbon emissions.

Toward that outcome, Pacific Northwest National Laboratory (PNNL) has developed an online decision tool, recently made publicly available by the Department of Energy (DOE), for cold climate heat pumps (CCHPs). The tool helps home contractors and installers achieve proper sizing and installation.

High-efficiency CCHPs are an emerging technology that enable consumers in colder locales, who perhaps worry that conventional heat pump models might not perform well in their climates, to reap the benefits of heat pump technology when they replace their heating and cooling systems.

“The CCHP units employ inverter-driven compressor operation. This means they can perform more effectively in cold climates, maintain homeowner comfort, and reduce heating costs,” said PNNL’s Vrushali Mendon, who led the team that designed the CCHP Decision Tool.

“The key to consumer satisfaction 

and broader deployment of this newer technology is proper installation of a unit that will efficiently and effectively meet heating and cooling needs,” Mendon added. “Homeowner, contractor, and installer endorsements of CCHPs are critical if we want to get these units into more homes and make progress on national climate mitigation efforts.”

DOE has also recently released a tool with similar aims, but for heat pump water heaters (HPWHs). The HPWH Installation Tool was made publicly available on July 24.

CCHPs: A key ingredient in the decarbonization formula

DOE has set ambitious goals to substantially reduce carbon emissions and mitigate climate change by 2050. DOE's decarbonization blueprint goal of 100 million heat pump conversions in existing homes by 2050 would require roughly five million conversions every year for the next 20 years. Such a transition away from oil- and gas-fired heating would expand use of electricity produced by clean sources, such as wind and solar power.

CCHPs offer advanced variable-speed compressors and controls that are designed to provide efficiency and comfort at the coldest outdoor air temperatures, reducing or eliminating the need for supplemental heating in nearly all climates.

One of the challenges for the broader purchase and installation of CCHPs involves reassuring consumers that the units, which can be more expensive than traditional heat pumps, will fully meet needs for comfort and cost. An improper size or installation can negate those benefits—along with homeowner satisfaction.

Because the CCHP is a newer technology, contractors and installers may not be adequately informed to answer consumer questions, select the properly sized unit, and make installation decisions that provide for seamless CCHP operation.

Decision tool delivers the latest information and guidance—at no cost

PNNL started working on the CCHP Decision Tool, a project funded under DOE’s Building Technologies Office, in 2022. Researchers tapped experts at PNNL, as well as heating, ventilation, and air conditioning contractors, implementers, other national laboratories, and regional energy-efficiency organizations, to provide insights and inform tool development. After several iterations—further honed by installer feedback—the tool was released for use on August ___.

Although the decision tool is publicly available, it was designed specifically for contractors and installers. Upon accessing the tool, the user responds to a series of questions, such as the square footage of the home and existing equipment (ducts, heating source type, existing cooling output capacity, etc.). Users also provide information about residential load calculations and the electrical panel.

After submitting requested information, users receive recommendations on the type of unit that’s needed and installation guidance.

“We believe the decision tool is very useful, but we want to make it even better. We are hoping that users will continue to provide feedback on their experiences so that we can fine-tune this resource and improve its usability and value," said Alek Parsons, a mechanical engineer at PNNL.

Along with Mendon and Parsons, developers included Trisha Watson and Yekaterina Pomiak.

Read DOE's announcement.