lsanderson: (Default)

Re: Gas vs Electicity

[personal profile] lsanderson 2019-03-14 03:40 pm (UTC)(link)
"To run" is the catch. And you have to go geothermal for the real high efficiency. Air-based heat pumps crap out around 0 C.
armiphlage: Ukraine (Default)

Re: Gas vs Electicity

[personal profile] armiphlage 2019-03-14 04:42 pm (UTC)(link)
The air-to-air heat pumps being put into condos in Toronto work down to about -15 C, although I expect efficiency suffers.
lsanderson: (Default)

Re: Gas vs Electicity

[personal profile] lsanderson 2019-03-14 05:34 pm (UTC)(link)

It seems they can go down a bit further to around -20 C, but at some point, they switch over to backup or straight electric resistance heat. This article from my exhaustive 30s Google research covers it better than me: https://www.nordicghp.com/2017/01/heat-pump-effective-temperature-range/

-20 C is a warm day in January around here so they're not much seen, although geothermal is inching forward here -- if nothing else you can see the above-ground part of the verticle field heat sinks.