Heat (thelemmy.club)
submitted 5 months ago by to c/science_memes@mander.xyz
 
you are viewing a single comment's thread
view the rest of the comments
[–] 277 points 5 months ago (40 children)

Resistive heaters still suck though because Heat pumps give you 200-400% efficiency. So heating wise, “100%” still less than maximally efficient.

(Not a violation of thermodynamics btw. Heat pumps use electricity to move heat energy that already exists, so the electric power in is often significantly smaller than the heat coming out of the device)

  • source
  • hideshow 40 child comments
  • [–] 420 points 5 months ago (28 children)
  • [–] 168 points 5 months ago (19 children)

    I'm so happy this man nerded out about heat pumps for a few hours.

    But now, all I see is inferior heaters.

  • source
  • parent
  • hideshow 19 child comments
  • [–] 70 points 5 months ago (2 children)
  • [–] 10 points 5 months ago (1 child)

    Having been on long term sick leave for 15 years means you have to do something with your time and I spend a lot of it learning new things to various depths. I now understand why some (though not all) older people are angry: when you know a lot about a lot you see how bad many things are. There's so much inefficiency, shit design, shit quality, shit shit everywhere. It hard to not let it get to you.

  • source
  • parent
  • hideshow 1 child comment
  • [–] 24 points 5 months ago (7 children)

    Who is that? I love heat pumps too and would happily listen to someone talk about them for hours

  • source
  • parent
  • hideshow 7 child comments
  • [–] 35 points 5 months ago (2 children)

    Search YouTube or revanced or whatever other free service for Technology connections, also the alt channel Technology Connextras.

  • source
  • parent
  • hideshow 2 child comments
  • [–] 13 points 5 months ago (5 children)
  • [–] 44 points 5 months ago (2 children)

    Bro's got multiple, hour+ long, videos about various types of heat pumps.

  • source
  • parent
  • hideshow 2 child comments
  • [–] 15 points 5 months ago (2 children)

    Hey that's the guy I see once a year at Christmas time!

  • source
  • parent
  • hideshow 2 child comments
  • [–] 15 points 5 months ago

    His videos are why I got a heat pump water heater instead of a standard one when mine died. I figure in summer I can hook the exhaust duct up to my hvac and get a bit of free air conditioning out of it, since I don't have AC yet. Tiny extra bonus piped straight to my bedroom.

  • source
  • parent
  • [–] 71 points 5 months ago* (last edited 5 months ago) (2 children)

    Resistive heaters still suck though

    • Resistive heaters are much more portable and flexible. (edit: and quiet)
    • Resistive heaters are a viable backup when heat pumps fail in extremely cold weather.
    • Resistive heaters are less money upfront for if you only have to use them occasionally.

    One is not directly beneath the other. Both have their place.

  • source
  • parent
  • hideshow 2 child comments
  • [–] 17 points 5 months ago (5 children)

    They're not 100% either, they make noises and emit light. That's loss

  • source
  • parent
  • hideshow 5 child comments
  • [–] 3 points 5 months ago (2 children)
  • [–] 7 points 5 months ago* (1 child)

    No, but you can use some forms of "light" to heat things

    If you want confusing specifics, light has negative absolute temperature

  • source
  • parent
  • hideshow 1 child comment
  • [–] 1 point 5 months ago* (last edited 5 months ago)

    Yeah, that is a bit confusing, i never thought about light being an example of one of those systems. Edit: looks like this applies only to laser light because light has a temperature of an emitting body, and lazing body has negative temperature

    my short interpretation would be like this

    A system with negative thermodynamic temperature is hotter than any system with a positive temperature. If a negative-temperature system and a positive-temperature system come in contact, heat will flow from the negative- to the positive-temperature system.

    This situation occurs because temperature is not really a measure of speed of particles, but rather a measure of entropy, and for ordinary objects entropy can increase infinitely, increasing temperature too. For systems with capped amount of states entropy reduces when energy is added, and that is negative thermodynamic temperature.

    So negative temperature is more energetic than positive, and because of that it heats up positive temperature object when in contact.

    Light kinda does that, but I am not sure I can come up with an explanation of how to measure its temperature and if it fits the definition

  • source
  • parent
  • [–] 16 points 5 months ago (1 child)

    Strictly speaking that's not efficiency, but a coefficient of performance.

    And funny enough the work energy doesn't even have to be electricity. It's actually mechanical energy, that is required and you could even power a heat pump with a steam or diesel engine.

  • source
  • parent
  • hideshow 1 child comment