If a machine is never 100% efficient transforming energy into work because part of the energy is converted into heat, does it mean an electric heater is 100% efficient? @showerthoughts@lemmy.world
You know how you turn on an electric heater and the filament begins to glow? That is energy being converted to light, so not 100% efficient.
Doesn’t the light turn into heat anyway as soon as it’s absorbed?
I mean if you want to go that route, we could just say that every speaker, light source, motor, etc is 100% efficient at generating heat because all of its energy output will eventually become heat.
Yes, except a heat pump is capable of being more than 100% efficient because the using the power to move heat around is more efficient than converting power directly to heat
but but muh thermodynamics
I get you are joking, but incase someone doesn’t see the /s. As the top comment said it’s easier to move heat around than creating it. Regardless if it’s warmer or colder outside there’s still energy there that we can use.
It’s easier to move your clothes from the laundry basket to the wardrobe, than to go out and buy new clothes (or is it?).
Technically, yes. Even the internal resistances outside of the heating elements eventually radiate into the space. Since the purpose is space heating, it’s not a waste product and they can be roughly considered 100% efficient.
The reason heat pumps are more efficient (i.e. around 300% or more) is not that they create more heat from the same amount of energy but because they concentrate and move existing heat from one source to another.
This is correct, but it’s also, it’s only 100% of the heat at that point in the circuit.
Technically, using natural gas to make electricity, then sending that electricity to an electric heater would be less efficient than burning that natural gas for heat at the source.
So it depends on where you start counting from.
