A lot of these issues "house will be uncomfortable cold" are because the way houses have been built previously (and still are in a lot of places) is horribly inefficient. In my country (it's -5c outside now, so not exactly warm) the building standards dictate new houses must consume no more than 15W/m2/year of heat energy for heating.
To convert that to US units, that means a 3000sqft house somewhere were electricity is $0.15c/kWh would cost $600/year to heat from electric baseboard heaters. If you have a heat pump you could bring that down to $200/year - and that's before you even consider solar.
I live in a 5 year old apartment, and haven't even turned on the heating this season, but it's still a comfortable 20c/68F inside.
To convert that to US units, that means a 3000sqft house somewhere were electricity is $0.15c/kWh would cost $600/year to heat from electric baseboard heaters. If you have a heat pump you could bring that down to $200/year - and that's before you even consider solar.
I live in a 5 year old apartment, and haven't even turned on the heating this season, but it's still a comfortable 20c/68F inside.