> 1) I would like to point out that Oslo does not have harsh winters. If you wish to publish an article regarding heat pumps and harsh winters travel a lot fart

> 1) I would like to point out that Oslo does not have harsh winters. If you wish to publish an article regarding heat pumps and harsh winters travel a lot farther north. Get into the -30C to -60 territory. What is the proportion of population that lives in IECC Zone 7 and above (or equivalent in each country): * https://basc.pnnl.gov/images/iecc-climate-zone-map https://basc.pnnl.gov/images/iecc-climate-zone-map There are folks in Climate Zone 7 in the northern tip of Maine (Caribou) that use heat pumps: * https://www.youtube.com/watch?v=OcwIz6heDss&t=43m21s https://www.youtube.com/watch?v=OcwIz6heDss&t=43m21s Folks running stuff in Alaska: * https://cchrc.org/air-source-heat-pumps/ https://cchrc.org/air-source-heat-pumps/ The design standards are that your system should be able to handle things for 99% of the days (on average), so during maybe up to 4 days your system would be running 100% of the time and still keeping up. The rest of time it's not running as hard. Look up ASHRAE's "design days": * https://www.airequipmentcompany.com/2021/what-does-design-day-really-mean/ https://www.airequipmentcompany.com/2021/what-does-design-da... * https://www.ashrae.org/technical-resources/bookstore/weather-data-center https://www.ashrae.org/technical-resources/bookstore/weather... Are there some portions of the population where a ccASHP won't make sense? Sure: but what population percentage, especially if you invest in some good air sealing and insulation first.