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> What would air-source heat pumps look like up here?

Air heat pumps dont work in 0F, you need an alternative. My heat pump has resistive heating coils for when it gets cold. https://en.wikipedia.org/wiki/Air_source_heat_pump#Efficienc...

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This isn't true. I live in MN and have a mini-split heat pump and a whole home air source heat pump that runs dual duty with my natural gas furnace. I currently run the cut off to switch at 20F. However both units will heat down to -20F. The mini-split struggles at that temp but the large unit still kicks out enough heat for the entire home.

I also replaced two natural gas water heaters with one 80 gallon air source heat pump water heater. It can run fully heat pump but also has coils. A "high demand" mode can run both simultaneously, but 95% of the year I run it in "efficiency" mode which is purely heat pump operation. It costs about $80-90/annually so far.

Current models work down to -10F without going linear. They'll still technically work beneath that but are basically the same as resistive electric at that point.

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