• Honytawk@lemmy.zip
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    4 months ago

    They are also one of the few things that are more than 100% energy efficient.

    300% to be exact. Because it uses some natural phenomena that just needs a little jump start and then can be maintained with little energy for massive air movement.

    • Aux@lemmy.world
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      4 months ago

      That efficiency metric doesn’t really reflect what’s going on. Of course moving stuff around is easier than heating it.

    • rbesfe@lemmy.ca
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      4 months ago

      The vapor compression cycle isn’t exactly natural, and the compressor still needs a bunch of energy to keep going once it’s started.

      • Zink@programming.dev
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        4 months ago

        Yeah I’m pretty sure my air conditioner uses more electrical energy than all my other appliances combined. Probably by an order of magnitude. No EV in my case of course.

      • WhatTrees@lemmy.blahaj.zone
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        4 months ago

        A few years ago I replaced our electric furnace with a heat pump which also gave us AC. Overall the yearly bill went up because we now had AC, but winter months usage is almost half of what it was before. Only matching on the extra cold days where the backup heat kicks in.

    • And009@reddthat.com
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      4 months ago

      Ah… energy doesn’t work that way. You can’t have a perpetually endless cycle with 100% efficiency in real world.

      • Ibuthyr@discuss.tchncs.de
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        4 months ago

        It’s called a CoP, Coefficient of Performance. It essentially is a factor of how much electricity you put in and how much cooling power comes out.

        Cooling towers can have a CoP of 12 and beyond, whereas compression cooling usually lingers at around 3 to 3.5. so at a CoP of 3 for instance, you could put in 1 kW of electricity and get 3 kW of cooling power.

      • ShrimpCurler@lemmy.dbzer0.com
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        4 months ago

        Well it’s not creating energy out of thin air. But it is moving it. So you get more energy moved than the amount of energy put in.

        • And009@reddthat.com
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          4 months ago

          Sure but that’s not the definition of efficiency, I’m sure it might be 5x more effective than traditional heaters of some sort from the power consumption perspective

      • KillingTimeItself@lemmy.dbzer0.com
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        4 months ago

        so technically, it’s not generating electricity, it’s moving heat from point A to point B, and believe it or not, 20f air still has a lot more heat energy in it than 0k air. So yeah, it’s more than 100% efficient. Comparing it to electric resistive heating, which is producing the heat directly from electricity, rather than moving it around.

        An electric resistive heater is 100% efficient, the efficiency of gas furnaces is measured similarly, though they hit about 90% eff, due to basic mechanics. Geothermal systems would also have greater than 100% efficiency as well, due to the fact that they just move fluid around, which is then cooled by the earth, (or warmed by it) though external heating wouldn’t be.