One could argue that it is 100% as every Watt that enters through the socket (not counting reactive energy) is going to become heat at some point in the very near future, including the air moved by fans, the photons emitted by the screen, etc etc.
replySo what happens to the 0.01%? Ah thats.. the light? The sound? Not sure.
replyMy bet would be some lucky photons that end up heading to outer space from some window. Hahaha
replyNot really? The best heaters are heat pumps which can under typical operation reach 300-500% efficiency (COP). Technically they aren't converting the electricity into heat, but for arguments sake here about heaters we only care about electricity consumed to heat generated.
reply> Technically they aren't converting the electricity into heat
replyIn fact they are converting 100% of it, they are just also collecting and moving additional heat in the process.
TIL, thanks, we mostly burn gas and coal
reply? that is just any computer
replyIsn't that lower than a purely resistive heater?
replyOnly if the resistive heater in question is DC or AC with reactive power compensation
replyA purely resistive heater, by definition, has no reactive component so there's no reactive power considerer.
replyThe 0.1% mentioned might be the light that the project produces.
Assuming you're not in an endless vacuum, the light will also become heat.
replyI think it's fair to separate it from the direct heat generation because if you look at second order effects like that, pretty much all of the energy ends up being radiated away as infrared in space.
replyIt's hardly a second order effect if you're talking about heating a space and the light is absorbed by the walls of that space.
replyIt's quite literally a second order effect. The first order effect is light generation, and a consequence of that effect is heat generation via light absorption.
replyDepends on where you want to draw the lines. Heating the room and emitting light could both be a second-order effect if you want to say that the first order is heating up the actual heater.
replyNice point! Would it be the same for sound that doesn't escape a room?
replyEvery computer is just space heater with side effect of computations.
replyThe same way every diesel engine is just oil stove with side effect of rotary motion. If the engine was in the back of the car you could totally put a pot on it and braise something.
My gaming laptop is surely 90% noise and heat (so heat?), but my m1 macbook… is less heat.. but still heat? From reading this thread everything will become heat, which sorta confuses me, but yeh i guess bitluni was nit talking about efficiency but more thermodynamically?!
replyA diesel engine is a very inefficient stove though, as only half (more or less, depending on the exact engine) of the energy is converted to heat, the leftover being mechanical energy.
replyModern yes. But olden times atmospheric diesels without turbo were really efficient space heaters.
replyGood ol' days.
replyThe Volkswagen 1.6D is probably the most reliable engine ever made. Only two failure modes - overheat or shitty fuel for the span of decades to break the fuel pump.
replyI’m curious about what you’re thinking of, but for both electric heaters and computers, essentially 100% of the input energy is converted to heat one way or another.
replyWhat you may be thinking of is efficiency when the output is intended to be something other than heat. In those cases, efficiency is lost because a significant proportion of the input energy is converted to heat.
But if heat output is what you’re interested in, I’m happy to report that 100% is a perfectly achievable, in fact hard to avoid, number!
Yeah, i was totally confused with efficiency, still curious about that 0.01% now tho
replyThere will be an LED somewhere, so some of it gets converted to light, rather than heat.
replyWhere the heat goes is the problem I have with that rating. An electric resistive stove is 100% efficient at converting input electricity to heat, but an induction stovetop is far better, better even than gas, for cooking on.
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