Their heat pumps incorporate back-up heaters. Into a single unit, that's rarely if ever used. It's sometimes called an auxiliary heater. In most climates backup

Their heat pumps incorporate back-up heaters. Into a single unit, that's rarely if ever used. It's sometimes called an auxiliary heater. In most climates backups are not required. > The good news is that, in most climates, modern cold weather heat pumps no longer need this type of backup heat source to supplement the heat being produced by the heat pump itself. If the power remains on, the better types of heat pumps can operate succesfully at temperatures as low as -15°F (or -25°C)... > Many modern high efficiency heat pump systems come with an integrated electric resistance heating system that functions as a back-up system at low temperatures. You do see them in the cold because they work fine. 60% of Norwegian homes have heat pumps. Sweden and Finland are around 40%. I believe that's the highest rate in all of Europe. [3] [1] https://www.ecohome.net/guides/3785/do-heat-pumps-need-a-backup-heat-source/ https://www.ecohome.net/guides/3785/do-heat-pumps-need-a-bac... [2] https://www.betterhomesbc.ca/products/do-i-need-a-backup-heat-source-for-my-heat-pump https://www.betterhomesbc.ca/products/do-i-need-a-backup-hea... [3] https://reasonstobecheerful.world/heat-pumps-norway-efficiency-emissions/ https://reasonstobecheerful.world/heat-pumps-norway-efficien...