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](h

Alvaro@social.graves.cl to Showerthoughts@lemmy.world – 246 points –

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

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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.