• sandbox@lemmy.world
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    4 months ago

    I’m not sure what you think is happening here, but energy is just being moved around. Air conditioners aren’t just belching out extra heat. If air conditioners were 100% efficient then they’d break even on heating, but in reality they’re much better than that, pretty much all air conditioners are at least 200% but most are more than that. This is achieved by using the same effect that your refrigerator uses - the radiator behind the freezer isn’t mega hot, right? You could look into vapor-compression refrigeration to learn more.

    • naturalgasbad@lemmy.caOP
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      4 months ago

      I don’t think you understand thermodynamics.

      ACs are heat pumps that use temperature differentials to move heat from one side to another. There are inherent losses there (e.g., moving 1000kJ of heat out of a room might take 500kJ, for 200% efficiency). That excess 500kJ is dumped outside into the world along with the 1000kJvof heat, creating a local heat island effect. That’s why ACs consume electricity, and that’s where the energy goes.

      The radiator behind the freezer isn’t mega hot because of advances in insulation that limit the amount of heat that needs to be moved and advances in efficiency when operating in specific temperature regimes. A modern fridge consumes 400kWh a year, which averages out to 1.1kWh/day, or 45W continuous draw. That’s about the same as a laptop charger. But, well, obviously your house is much larger than your fridge. A fridge might average 400L in volume, but your house averages more like 600000L (1500x more).

      If you could move heat around without incurring losses, you could use that to construct a perpetual motion machine. Conservation of energy is a thing and entropy always increases.