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it was recently pointed out to me that electrical generators don't actually generate _electricity_ since energy can't be created or destroyed. they convert energy. but then, what are they generating?

generators are sources of _low entropy_, in the form of electric current, and I'm still trying to wrap my head around that.

@ashfurrow They are actually pumps. They generate difference of electric potentials — they use the energy you give them to sort the positively charged particles separate from the negatively charged particles — which is technically some kind of order, so it lowers entropy.

@deshipu yeah exactly. once I realized the Sun is a source of low entropy (which, in turn, drives lower entropy through the water cycle for hydroelectric generators, etc) things started to make more sense. but still pretty out there!

@ashfurrow The problem I have with the entropy-based approaches to understanding energy is that entropy is very relative. I mean, the choice to call this particular configuration of particles "ordered" and all the other configurations "less ordered" is quite arbitrary, and you can destroy entropy (and thus generate energy) basically with just the mental activity of finding patterns.

@ashfurrow I tend to remember that to keep up with conservation, whenever a magnetic field (from the rotating generator turbine) induces a current in a wire, that current induces it's own magnetic field that OPPOSES the field that induced it

It's wonky, but it provides a torque back on the generator and is why you can't just use a generator "for free"

@mdszy thanks for the analogy. It took me way too long to wrap my head around why grounding the power grid even works, so I’m catching up to these concepts slowly 😅

At least I think I got it hahaha

@brunoph it's one of the few things I remember from my E&M fields class lol

@ashfurrow Or you know, they generate electricity because common vernacular is still a valid way of expressing the more precise terms in day to day conversations.

@ashfurrow they're moving entropy around, the low-entropy fuel gets turned into high entropy hot air and carbon dioxide

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