And despite the handwringing, air source heat pumps can work fine in pretty cold places (eg Norway).
You can, right now, buy air source heat pumps rated to -28C (-14F). While not enough for record lows in, say, Chicago or Toronto, it's plenty for places like New York, Seattle, and Vancouver.
Rated to -14F doesn’t really bring a lot of comfort. NYC has reached that temperature; NJ has reached -34. In a typical winter you might stay above zero every minute of every day. But when that big arctic blast comes through and your heat pump efficiency tanks, right at the same time your house is bleeding its heat faster than ever, that could be pretty dangerous. So, every heat pump installer recommends a having a backup (at least the dozen I’ve talked to in the Northeast US). it’s hard to convince regular people that heat pumps are the future when you’re also told to have a backup.
This year I installed a heat pump with a 10kW auxiliary heater for my home in southern Ontario. With an appropriate air handler, both the heat pump and auxiliary heater can run at the same time. The setup seems fine to me.
If anything having a backup heat source makes me feel secure. A lot of things can go wrong with a gas furnace; some things can go wrong with a heat pump; but 10kW of electric restive heat is dead simple and just by itself it can provide 34000 BTU/h, which is 60% of the output of my old gas furnace. I don't think the duty cycle of my gas furnace ever exceeded 60% running time.
The auxiliary heater consists of two 5kW heaters, so even if one fails, there is still the other.
True, but you could always have a battery back up for the blower and such.
Do you have a wood burning back up? At my house in Massachusetts, we had a wood-burning stove that we could always fire up in a pinch. It never came to that, but it felt good knowing that we can always just burn a super hot fire and not freeze to death.
While I could have had a battery backup for the blower, I never did, so I guess I'm not missing out. :)
I live in an urban environment, so I'm not too worried about losing power for an extended period of time, and if I do I would probably just leave temporarily.
In my rural living fantasy I have a Ford F150 Lightning which I use as a "portable" backup battery that can be recharged by driving it to a Level 3 charging station. That and either a pellet stove and/or a Masonry Heater fireplace that sits opposite to a large equator (south) facing window.
It sounds like you're suffering from the typical grift where contractors over-charge because they don't want to do the work you're asking for. This is common but its a problem with contractors. The standard way to build in the US involves illegal immigrants doing poor quality work.
If there is a heat pump rated to -14F and an area has historic lows of -34F it sounds like a bit more than just grifting going on. These people are setting up a system where, if everything works to spec, the customer may well freeze to death one winter.
I don't know much about how heat pump performance degrades, but going in to a life-and-death situation where the main heat system is operating outside rated performance seems like poor planning.
No one is going to install a system that puts you in a life or death situation. Worst case is it uses resistive heating to deal with extreme cold. Systems like that are widespread and still save people money.
Despite being effective at low temperatures when properly sized, and with traditional heating when needed, they aren't efficient during the coldest days when you have a leaky house. That's where ground source systems clean up.
My main issue with GS is the complexity. gas furnaces are pretty bulletproof; in my experience they are really reliable and east to fix (or just replace in a one-day job) if there are issues. Air source is a little more complicated to fix but not too bad. Ground source though, part of the system is literally buried underground!
