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Heat
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SmoothLiquidation lemmy.world SmoothLiquidation@lemmy.world
Joined: 2023-06-17
#52 · Quote Reply

Most of the heating energy would actually be IR, which many types of window glass will be designed to reflect. It probably depends on what kind of coatings are used. Basically all car windows block IR to help keep the inside of the car cool in the sun.

It’s a silly thing, but if it glows orange, and if any of that orange light escapes or is visible from the window, it is not 100% efficient. But this is just pedantic in reality, even cheap heaters will do a good job of converting electricity into heat.

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Apathy Tree lemmy.dbzer0.com ApathyTree@lemmy.dbzer0.com
Joined: 2023-06-23
#53 · Quote Reply

Did someone say heat pumps?

His videos are why I got a heat pump water heater instead of a standard one when mine died. I figure in summer I can hook the exhaust duct up to my hvac and get a bit of free air conditioning out of it, since I don't have AC yet. Tiny extra bonus piped straight to my bedroom.

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outerspace lemmy.zip outerspace@lemmy.zip
Joined: 2024-01-06
#54 · Quote Reply

They're not 100% either, they make noises and emit light. That's loss

Isn't light heat?

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Custard lemmy.world Custard@lemmy.world
Joined: 2023-06-20
#55 · Quote Reply

Did someone say heat pumps?

Hey that's the guy I see once a year at Christmas time!

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ryannathans aussie.zone ryannathans@aussie.zone
Joined: 2023-09-20
#56 · (edited) Quote Reply

Isn't light heat?

No, but you can use some forms of "light" to heat things

If you want confusing specifics, light has negative absolute temperature

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_stranger_ lemmy.world _stranger_@lemmy.world
Joined: 2023-08-02
#57 · Quote Reply

They're not 100% either, they make noises and emit light. That's loss

And that light? Albert Einstein.

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SubArcticTundra lemmy.ml SubArcticTundra@lemmy.ml
Joined: 2023-06-03
#58 · Quote Reply

Hey that's the guy I see once a year at Christmas time!

Coming down your chimney?

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SubArcticTundra lemmy.ml SubArcticTundra@lemmy.ml
Joined: 2023-06-03
#59 · Quote Reply

Who is that? I love heat pumps too and would happily listen to someone talk about them for hours

This man managed to make a 30 minute video about door stoppers that I watched to the end

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starik lemmy.zip starik@lemmy.zip
Joined: 2025-12-08
#60 · Quote Reply

[deleted]
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AckPhttt beehaw.org AckPhttt@beehaw.org
Joined: 2023-09-05
#61 · Quote Reply

Only if that light escapes through a window. Otherwise, it is heat.

Or chemical reactions.

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weastie lemmy.world weastie@lemmy.world
Joined: 2023-07-03
#62 · Quote Reply

[deleted]

Yup, that little buzz / hum is technically lost energy

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33550336 lemmy.world 33550336@lemmy.world
Joined: 2024-02-22
#63 · Quote Reply

Even if the heater's energy partially is not wasted by a sound, it certainly is by generating magnetic field.

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mceldritch lemmy.world mceldritch@lemmy.world
Joined: 2023-07-08
#64 · Quote Reply

Did someone say heat pumps?

I came here to see a picture of this man.

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ViperActual sh.itjust.works ViperActual@sh.itjust.works
Joined: 2023-06-13
#65 · Quote Reply

Coming down your chimney?

No he'll be criticizing your choice of Christmas string lights, or lack thereof.

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bebabalula feddit.dk bebabalula@feddit.dk
Joined: 2024-08-28
#66 · Quote Reply

Yup, that little buzz / hum is technically lost energy

Well, if you want to go all “technically” on this, then that sound technically dissipates as heat when it is absorbed by the interior of the room.

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M0oP0o mander.xyz M0oP0o@mander.xyz
Joined: 2023-06-13
#67 · Quote Reply

Unless your heater's cable is ridiculously long, it'll be in the right area. The wires in the wall aren't part of the heater and don't factor into its efficiency.

Don't you plug your 50 meter long cord in outside, run it though all the stuff you never want hot and then into the window to run your space heater? I mean if you are heating a room, why would the plug be in that same room?

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Phoenixz lemmy.ca phoenixz@lemmy.ca
Joined: 2023-06-10
#68 · Quote Reply

Isn't there also visible, non heating light coming off them.?

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Bysmuth lemmy.zip Bysmuth@lemmy.zip
Joined: 2024-07-16
#69 · Quote Reply

Isn't there also visible, non heating light coming off them.?

I think that light also becomes heat again once it strikes a surface

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SpongyAneurysm feddit.org SpongyAneurysm@feddit.org
Joined: 2025-06-29
#70 · Quote Reply

Resistive heaters still suck though because Heat pumps give you 200-400% efficiency. So heating wise, “100%” still less than maximally efficient. (Not a violation of thermodynamics btw. Heat pumps use electricity to move heat energy that already exists, so the electric power in is often significantly smaller than the heat coming out of the device)

Strictly speaking that's not efficiency, but a coefficient of performance.

And funny enough the work energy doesn't even have to be electricity. It's actually mechanical energy, that is required and you could even power a heat pump with a steam or diesel engine.

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scratchee feddit.uk scratchee@feddit.uk
Joined: 2023-07-16
#71 · Quote Reply

Well, if you want to go all “technically” on this, then that sound technically dissipates as heat when it is absorbed by the interior of the room.

Some of it does. Most of it even, but not all of it

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scratchee feddit.uk scratchee@feddit.uk
Joined: 2023-07-16
#72 · Quote Reply

I think that light also becomes heat again once it strikes a surface

Mostly, but not entirely.

Most thing you struggle to approach anywhere near 100% efficient, heating is a bit easier in that you can get a lot closer, but you’ll still hit limits before reaching 100%.

Saying inefficiencies are lost as heat is really a lazy simplification, inefficiencies are lost as anything
It just turns out that 95% of anything is heat, from entropies perspective.

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da_cow (she/her) feddit.org cows_are_underrated@feddit.org
Joined: 2024-06-22
#73 · Quote Reply

Yep, every electric device is a toaster, some are just super inefficient at it.

Remember: Every device is a smoke machine if you use it wring enough.

Also: Every electrical device is filled with smoke and the job of electricians is to stop the smoke from escaping, which would render the device useless.

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bryndos fedia.io bryndos@fedia.io
Joined: 2025-07-28
#74 · Quote Reply

Don't you plug your 50 meter long cord in outside, run it though all the stuff you never want hot and then into the window to run your space heater? I mean if you are heating a room, why would the plug be in that same room?

Fine for electrical efficiency, but in terms of fuel efficiency I can get into an odd situation where I burn the same amount of (say methane) gas in my room, vs in a remote power station (where we might assume any heat losses are not useful). I could end up getting more useful heat out of the same fuel using a nominally less efficient gas heater vs an electric one.

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krashmo lemmy.world krashmo@lemmy.world
Joined: 2023-07-03
#75 · Quote Reply

Search YouTube or revanced or whatever other free service for Technology connections, also the alt channel Technology Connextras.

I watched his video on renewable energy and it was awesome. That ending was very unexpected but he killed it. Thanks for the info

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Melllvar startrek.website charonn0@startrek.website
Joined: 2023-07-03
#76 · Quote Reply

Remember: Every device is a smoke machine if you use it wring enough. Also: Every electrical device is filled with smoke and the job of electricians is to stop the smoke from escaping, which would render the device useless.

The correct technical term is magic smoke.

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da_cow (she/her) feddit.org cows_are_underrated@feddit.org
Joined: 2024-06-22
#77 · Quote Reply

The correct technical term is magic smoke.

Today I learned

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M0oP0o mander.xyz M0oP0o@mander.xyz
Joined: 2023-06-13
#78 · Quote Reply

Fine for electrical efficiency, but in terms of fuel efficiency I can get into an odd situation where I burn the same amount of (say methane) gas in my room, vs in a remote power station (where we might assume any heat losses are not useful). I could end up getting more useful heat out of the same fuel using a nominally less efficient gas heater vs an electric one.

Ah yes, clearly you should burn coal/natural gas/fissionable material in your home. Very reasonable.

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pruwyben discuss.tchncs.de pruwybn@discuss.tchncs.de
Joined: 2023-06-12
#79 · Quote Reply

Every electric device is a heater. Some just do other things too.

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Agent641 lemmy.world Agent641@lemmy.world
Joined: 2023-07-12
#80 · Quote Reply

Software engineers fixing a prod-down bug on Friday afternoons operate at 100%

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Danitos reddthat.com Danitos@reddthat.com
Joined: 2024-01-17
#81 · Quote Reply

Some of it does. Most of it even, but not all of it

Why not? My underestanding is that 100% energy of a sound wave will ultimately be transformed to kinetic energy to particles in the room, be it a wall's, an ear drum's or air's.

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Beangut lemmy.world Beangut@lemmy.world
Joined: 2026-03-17
#82 · Quote Reply

Software engineers fixing a prod-down bug on Friday afternoons operate at 100%

Thanks for giving me flashbacks I didn't know I had

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bufalo1973 piefed.social bufalo1973@piefed.social
Joined: 2025-09-01
#83 · Quote Reply

I'm not an expert but, would it be that one kind of energy can't be 100% transformed to just one other kind of energy? That in any translation the result is always more than one kind of energy?

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kkj lemmy.dbzer0.com kkj@lemmy.dbzer0.com
Joined: 2025-03-08
#84 · Quote Reply

Every electric device is a heater. Some just do other things too.

A brushless motor only converts ~5% of its input to heat. That's low enough that you can reasonably call it a side effect.

Now, a computer, that's a heater that happens to produce math as a side effect. 100% of its input ends up as heat.

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kkj lemmy.dbzer0.com kkj@lemmy.dbzer0.com
Joined: 2025-03-08
#85 · Quote Reply

A heat pump will drop to 100% efficiency in cold enough weather.

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9point6 lemmy.world 9point6@lemmy.world
Joined: 2023-06-12
#86 · (edited) Quote Reply

Isn't there also visible, non heating light coming off them.?

What about a combination heater/lamp where the lamp part is just incandescence

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EvenOdds lemmy.zip EvenOdds@lemmy.zip
Joined: 2025-06-29
#87 · Quote Reply

boy are you one of today's lucky 10,000!

What do you mean lucky 10,000?

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stormdelay sh.itjust.works stormdelay@sh.itjust.works
Joined: 2023-06-23
#88 · Quote Reply

What do you mean lucky 10,000?

https://xkcd.com/1053/

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ChickenLadyLovesLife lemmy.world ChickenLadyLovesLife@lemmy.world
Joined: 2023-06-16
#89 · Quote Reply

Isn't there also visible, non heating light coming off them.?

My oil heater makes gurgling noises so that acoustic energy is lost. It would also just heat up the room eventually, but I usually have a window open in winter so a tiny bit is lost that way.

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lonefighter sh.itjust.works lonefighter@sh.itjust.works
Joined: 2024-03-12
#90 · Quote Reply

A brushless motor only converts ~5% of its input to heat. That's low enough that you can reasonably call it a side effect. Now, a computer, that's a heater that happens to produce math as a side effect. 100% of its input ends up as heat.

I love firing up my PC and gaming on cold winter nights. A well placed fan or two and I can spread it through my entire apartment and the heat won't kick on all night. Ends up saving me money, my heater costs way more than my PC to run.

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zergtoshi lemmy.world zergtoshi@lemmy.world
Joined: 2023-10-24
#91 · Quote Reply

I think that light also becomes heat again once it strikes a surface

If all became heat upon striking a surface that would make lighting anything pretty impossible and most would be dark.

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captcha lemmy.frozeninferno.xyz captcha@lemmy.frozeninferno.xyz
Joined: 2026-03-28
#92 · (edited) Quote Reply

No, but you can use some forms of "light" to heat things If you want confusing specifics, light has negative absolute temperature

Yeah, that is a bit confusing, i never thought about light being an example of one of those systems. Edit: looks like this applies only to laser light because light has a temperature of an emitting body, and lazing body has negative temperature

my short interpretation would be like this

A system with negative thermodynamic temperature is hotter than any system with a positive temperature. If a negative-temperature system and a positive-temperature system come in contact, heat will flow from the negative- to the positive-temperature system.

This situation occurs because temperature is not really a measure of speed of particles, but rather a measure of entropy, and for ordinary objects entropy can increase infinitely, increasing temperature too. For systems with capped amount of states entropy reduces when energy is added, and that is negative thermodynamic temperature.

So negative temperature is more energetic than positive, and because of that it heats up positive temperature object when in contact.

Light kinda does that, but I am not sure I can come up with an explanation of how to measure its temperature and if it fits the definition

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BradleyUffner lemmy.world BradleyUffner@lemmy.world
Joined: 2023-06-11
#93 · (edited) Quote Reply

A brushless motor only converts ~5% of its input to heat. That's low enough that you can reasonably call it a side effect. Now, a computer, that's a heater that happens to produce math as a side effect. 100% of its input ends up as heat.

It all becomes heat eventually in the end though. Sometimes it's just a multi step complex process outside the physical bounds of the heater.

Wait a sec, is the universe just God's space heater?

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0xDREADBEEF lemmy.dbzer0.com dreadbeef@lemmy.dbzer0.com
Joined: 2024-12-18
#94 · Quote Reply

A brushless motor only converts ~5% of its input to heat. That's low enough that you can reasonably call it a side effect. Now, a computer, that's a heater that happens to produce math as a side effect. 100% of its input ends up as heat.

It might output the results of a computation once in a while though

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Mwa thelemmy.club Mwa@thelemmy.club
Joined: 2024-06-27
#95 · Quote Reply

its the Potis Meme!

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TwilightKiddy programming.dev TwilightKiddy@programming.dev
Joined: 2023-06-12
#96 · (edited) Quote Reply

Strictly speaking that's not efficiency, but a coefficient of performance. And funny enough the work energy doesn't even have to be electricity. It's actually mechanical energy, that is required and you could even power a heat pump with a steam or diesel engine.

God I spent too much time arguing with people who say that heat pumps are >100% efficient...

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potpotato lemmy.world potpotato@lemmy.world
Joined: 2024-02-24
#97 · Quote Reply

It all becomes heat eventually in the end though. Sometimes it's just a multi step complex process outside the physical bounds of the heater. Wait a sec, is the universe just God's space heater?

In god’s universe it is winter and that’s why the earth is heating up. It says so right in Ecclesiasties. Boom, toasted climate change nerds.

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Etterra discuss.online Etterra@discuss.online
Joined: 2024-12-10
#98 · Quote Reply

Any resistance heater, but the most efficient ≠ the most cost effective.

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Zerush lemmy.ml Zerush@lemmy.ml
Joined: 2021-04-25
#99 · Quote Reply

Also a question of optimizing its use

vgy.me

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VAK lemmy.world VAK@lemmy.world
Joined: 2026-03-18
#100 · Quote Reply

I'm not an expert but, would it be that one kind of energy can't be 100% transformed to just one other kind of energy? That in any translation the result is always more than one kind of energy?

No, it just means there is at least some going into heat in thermodynamic processes. Inevitable with atoms jostling in macroscopic systems.

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Deconceptualist leminal.space Deconceptualist@leminal.space
Joined: 2025-06-29
#101 · Quote Reply

Remember: Every device is a smoke machine if you use it wring enough. Also: Every electrical device is filled with smoke and the job of electricians is to stop the smoke from escaping, which would render the device useless.

Hehe yes, we called it "magic smoke" in the early days of my engineering studies. Devices run on magic smoke so they stop working if the magic escapes.

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