this post was submitted on 17 Feb 2024
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Showerthoughts

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A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The best ones are thoughts that many people can relate to and they find something funny or interesting in regular stuff.

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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? @[email protected]

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[–] [email protected] 49 points 8 months ago (2 children)

Doesn’t the light turn into heat anyway as soon as it’s absorbed?

[–] [email protected] 42 points 8 months ago (3 children)

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.

[–] [email protected] 42 points 8 months ago (2 children)

That is also completely true, but meaningless because heat generation is not the purpose of these devices. However, if you use them in a building heated by a thermostat-controlled electric heater, you’re effectivhly running them for free.

[–] [email protected] 14 points 8 months ago

I‘m was using two old servers with folding@home running as space heaters in the winter. I got them for dirt cheap and thought if I convert electricity into heat, I might as well do something good with it. Also nice opportunity to run a minecraft server for the kids during that time.

[–] [email protected] 1 points 8 months ago* (last edited 8 months ago) (1 children)

I‘m was using two old servers with folding@home running as space heaters in the winter. I got them for dirt cheap and thought if I convert electricity into heat, I might as well do something good with it. Also nice opportunity to run a minecraft server for the kids during that time.

[–] [email protected] 4 points 8 months ago (2 children)

You double-posted this comment, FYI

[–] [email protected] 8 points 8 months ago

One for each server.

[–] [email protected] 7 points 8 months ago

It's still efficient because both those comments will end up as heat anyway.

[–] [email protected] 3 points 8 months ago

Energy can neither be created nor destroyed so in the grand scheme of things, everything is 100% energy efficient one way or another.

[–] [email protected] 1 points 8 months ago

I suggest we submit proposals to define "100%" and "efficient" before we design the experiment

[–] sukhmel 8 points 8 months ago (2 children)

The visible part of the spectrum is likely going to be absorbed somewhere far away from the place you're trying to heat up. Also, I'm not educated enough to tell if there will be further losses of energy

[–] [email protected] 4 points 8 months ago (1 children)

If it’s in a room the visible radiation will still just heat up the room. If you’re using it outdoors and point it away then yeah you’ll have some waste.

[–] sukhmel 4 points 8 months ago

Not sure if visible radiation that leaves through a transparent window will still heat up only inside the room, that what I meant. Probably should have phrased it better

[–] [email protected] 3 points 8 months ago* (last edited 8 months ago)

that's only true if you shine it out a very large the window

normally windows cover a quite small fraction of a rooms surface area

but sure, if a few fractions of a percent leave through a window, i guess its technically not a 100% effective space heater, if we define the work as heating only the relevant room.