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
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
Heaters sometimes produce a little light or sound, so not 100%, but very close.
The sound will eventually dissipate in the air as heat. The light will be absorbed into surfaces, like any other radiation, as heat. Still 100%, but with a couple extra stops along the way.
All energy output will eventually become heat. Why bother measuring efficiency at all if we’re counting those aftereffects?
Only heaters are a machine where the “good” output is one you want to be heat.
For other devices the heat is the bad part.
But since your goal with a heater… is to generate heat… and all energy eventually will become heat, it is close to 100% efficient.
If you can hear the heater’s sound it makes in a room/area you don’t want to be heating though, now it’s <100% efficient as a tiny bit of energy became heat that heated the non ideal location.
Fun fact: this phenomenon is what causes the infamous “hot ear” effect that many people suffer from every day.
Yeah I mean you’d have to consider the practical factors such as how quickly or evenly they can heat up a room rather than worry so much about the raw efficiency.