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
Essentially all electrical devices are, in addition to whatever else they do, also basically 100% efficient space heaters. A PC running on 300 watts is doing things with that 300 watts but it all ends up as heat, the vast majority of which stays in the room. A light bulb puts out light, but little of that light leaves the house, it’s all getting reflected and absorbed until it’s mostly a heater in your house.
Consuming energy to do something the device isn’t intended to do is the definition of inefficiency. You’ve basically redefined efficiency so as to make it meaningless.
What are you confused about?
That’s why they phrased it “also basically 100% efficient space heaters.”
Every electric device is a something% effective whatever work they are meant for device, but ALSO a 100% effective space heater.
That second part is meaningless to the devices normal function, but very relevant to the post question.
It would be meaningless, were it not for the context of the question it is answering. All of the electrical energy consumed is being turned in to heat in all those cases making it indeed possible to make a 100% efficient heater using electricity as was asked. The fact that that is orthogonal to the purpose of the machines is only relevant in as much as that’s why they were chosen as illustrative examples, showing that even when you’re not trying to, you end up making 100% efficient space heaters from electrical devices.
They didn’t redefine efficiency. They changed the purpose scoping.
If a light bulb gets dinged for leaking light outside of the house, then a computer, a computational and informational device, should also get dinged for any light not absorbed by eyeballs and any errant processes/calculations running without discrete need
The light leaving the house decreases heating efficiency because the energy quite literally went out the window. If you run needless calculations or look away from the monitor, that energy still ends up heating your house