[galangalalgol]

Keeping your house at 80F when its 115F outside would seem to use less energy than keeping your house at 60F when it is -1F out. Maybe humidity makes it closer to even? For me one bill was gas and one was electric, so harder to compare. I'll ask some coworkers with only a heat pump.

[bombcar]

Part of it is everything creates waste heat - so a well insulated house can take a looooong time to cool (my furnace died in the winter and I didn’t notice for over a week).

And you can survive “unaided” quite low (sleeping bags rated to -30°?) but there is a heat point where you die if you cannot escape it somehow.

[pdonis]

> Maybe humidity makes it closer to even?

If the humidity is high enough, it can take it past even. But you won't find that out by comparing summer and winter numbers in the same location, because there aren't a significant number of locations that have both summer and winter conditions severe enough to push the numbers. You would want to compare, say, Canada in winter with south Florida or south Texas in summer (or, for even more extreme, northern Scandinavia in winter with southeast Asia or equatorial Africa in summer).

[galangalalgol]

Scandinavia in winter won't usually be a heat pump to air though right? Don't they heatpump from geothermal?

Even just locally here the 25 degree F differential with ~50% relative humidity in summer would be interesting to compare to the 60 degree F differential in winter. Maybe those ultra efficient hygroscopic dehumidifiers will finally enter production.

And heat pumping to geothermal for summer might help too. I know some people locally do that. Big investment though.

[yesbabyyes]

Sweden can range from -25 to 35 °C. Heat pumps are common, both downhole heat exchangers (rock heat we call it) and air source heat pumps, among home owners.

Central heating is also common and often heated by garbage.

[dahfizz]

Yes, but a lot of that heat comes "for free" from cooking, your fridge/computer/apliances, hot water usage, body heat, etc.

I have a heat pump for heating and cooling, and my electric bills are only slightly higher in winter (5-10%).