Colder climate is exactly where you want to use heat pumps. The numbers for Norway in 2022 (https://www.novap.no/om-varmepumper https://www.novap.no/om-varmepum

Colder climate is exactly where you want to use heat pumps. The numbers for Norway in 2022 (https://www.novap.no/om-varmepumper https://www.novap.no/om-varmepumper) is 58% of Norwegian homes (houses) have a heat pump installed, 34% in service industries, 8% in other industries. For homes air-to-air dominates (more than 90%). And since then this has just increased even more (and older heat pumps are being replaced with newer and better ones as well). As an aside, many have commented on the claim that heat pumps make more sense with a well insulated building, arguing that it should be the other way around. The reason that you do want a well insulated building is simply that air-to-air heat pumps are limited to typically less than around 8kW heating capacity, and with a well insulated house you can heat a large area with that, with bad insulation you can't, and you would need a much more expensive type - typically not those sold to home owners (or buy several pumps, exploding the costs). In addition to that, a heat pump is more efficient when it doesn't have to run at maximum capacity. The heat pumps sold in the Nordic countries are typically around $3000 including installation. And they're highly efficient.