For a full year I have lived in a house that has one of these.

It’s a hot summer and I’m delighted that it can not only heat but also keep my place cool!

Now I got an email from my electricity provider that during the last weeks (I was at home most of the time) my electricity consumption was roughly twice of what it usually is.

Hence my question: compared to its heating capabilities, does a heat pump use much more electricity for cooling?

I’m not looking for a scientific breakdown.

edit:

Thanks for all replies so far. Cooling seems to be trickier than heating and I should keep my windows closed, which just feels wrong during summer… but apart from that cooling does not use more energy than heating.

  • A_norny_mousse@feddit.orgOP
    0·
    15 days ago

    it uses the same amount as when it’s heating

    Thanks, I’ll take your word for it. So - if it cools the place from, say, 29 degrees outside to 22 degrees inside, that’s the same as warming it from 15 degrees outside to 22 inside?

    And yeah, it’s been running a lot. I guess there’s no mystery here. Only the next bill will tell (the email sneakily did not tell me any amounts, just some colorful graph. They want me to use their app).

    • cecilkorik@lemmy.caEnglish
      0·
      15 days ago

      So - if it cools the place from, say, 29 degrees outside to 22 degrees inside, that’s the same as warming it from 15 degrees outside to 22 inside?

      Oh my, not at all. If it runs for 1 hour continuously in cooling mode that’s going to be electrically largely equivalent to running for 1 hour continuously in heating mode (again, provided it’s not variable speed). Even then the electrical load will vary slightly according to various conditions. The actual temperatures achieved though, depend entirely on the thermodynamics of the system (both inside the pump itself and your whole house and the environment it’s in) which are extremely dynamic and complicated. There are almost no simple, linear relationships you can use to approximate what is actually going on. Even the approximate calculations that HVAC installers do called “Manual J” are hugely idealized and oversimplified. You’ve got things going on like solar heat gain through windows, heat losses through insulation, and heat transfer through gaps in the insulation, air losses through vents and doors and windows and gaps that are specific to your individual home and that you can’t even really measure accurately. It’s a very difficult thing to even attempt to compute or simulate no matter how much we try to develop models that accurately estimate things. On a larger scale, this is why we still struggle to accurately predict the weather.

      Only the next bill will tell

      That’s a reasonable position. You can make all the estimates you want but at the end of the day the only thing that really matters is what you get billed for and that will tell you the truth about what’s actually happening in your house, environment, climate, and situation. I would be confident that given the same temperature conditions you really won’t see much practical difference in electrical usage between a heat pump in cooling mode and an air conditioner (if anything they tend to be somewhat more efficient just due to better design and higher build quality). But you won’t know the true situation until all the measurements are actually done and posted to your bill, and even then you won’t be able to directly compare them because there are so many other variables that are always changing.