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by thrashh 1085 days ago
Well the word “efficient” always needs context. You have to define the goal first before you can define efficiency.

OP said electrical efficient so the goal is conversion of electricity to heat and it’s 100% efficient.

Even an electric heater compared to a propane heater is more electrically and energy efficient, but it’s not as storage-efficient (because fossil fuel gases have much higher energy density per volume AND weight than lithium batteries).

A heat pump is more electric bill-efficient.

1 comments

> OP said electrical efficient so the goal is conversion of electricity to heat and it’s 100% efficient.

I am not an engineer and I am only nitpicking to have fun, so don't engage me if it's not fun, but doesn't some of the energy go into degradation of the materials used to build the device?

Yes, but energy is not consumed by that process, it is only converted into heat. The degradation usually is a result of the heat produced. If we’re talking about mater to energy transitions, we need to start talking about special relativity.

I said 100% electrical efficiency because from the prongs of the plug, through the conductors in the appliance cord, the rheostat, all electrical connection and contact points, and of course the hearing element itself all will product heat as a consequence of electricity flowing through, and being resisted by, it’s various components.

It was pointed out that this does not mean “energy bill efficient” which is totally correct: this whole thing is a somewhat silly thought experiment to consider what it really means for something to be efficient.