• batmaniam@lemmy.world
    link
    fedilink
    English
    arrow-up
    12
    ·
    1 year ago

    As others have said yes, thats an air conditioner, but to expand: that’s why the outside of an air conditioner (either one of the big ground mounted ones outside or the window ones) gets hot while it’s operating. You could technically just mount your window AC backwards.

    To expand further, that’s part of why heat-pumps weren’t in expanded use for a while. In the summer you’re extracting hot from the room and putting the hot outside, so your heat exchanger is hot. But in the winter when you’re extracting heat from outside and putting it inside, you make the heat exchanger outside more cold. So cold, infact, that icing becomes an issue, and when it ices over it’s less good at extracting heat. There are some neat tricks modern heat-pumps use to avoid icing over their outside heat exchanger (including running backwards to extract heat from inside and heat up the coils for a bit).

    It’s also why you saw early adoption of heat-pumps in areas where people might need both heating and cooling, but it didn’t get bitter cold.

    Another way this is avoided in some cases is to simply bury the heat exchanger to a depth below the frost line, where it can’t freeze. Then you can add/extract as much heat as you want. That’s geothermal heating/cooling. In some cases geothermal may be passive (ie: you’re just circulating a fluid and temperature you get is what you get), but it’s real strength is as a heat exchanger.

    In fact, with the ground being able to accept/source as much heat as you want, you could actually place the “topside” exchanger in an area where you weren’t trying to control the temp, and take advantage of the temperature difference to create power. Thats geothermal power. However, the efficiency and payback of that is based on the difference in temperature, which is why you only see it in instances where there’s some natural source of higher temp heat underground. I suppose geothermal power would work just as well with a natural source of low temp cold (like the opposite of lava), but I’m hard pressed to imagine what that would be.