Does unplugging a device that isn’t turned on actually save electricity?

I understand that some devices continue to use power when they aren’t in use, like a computer. But what about a simple device, like a toaster? Is anything saved by unplugging it? What about a 100′ foot extention cord that I leave plugged into my garage outlet? Can just a cord lead or consume energy? Doesn’t make sense to me, but some people believe that.

A device in which the current does not reach the load does not consume power. Plugging or unplugging such a device makes no difference so far as power consumption is concerned.

However, a device in standby mode has some active loads and such device consumes power unless power supply to that load is totally cut off. Eg. when a TV is switched off using the remote control, the SMPS section inside the TV is still feeding power to section housing the infrared sensor. As such, though the Cathode Ray Tube is off, the SMPS and remote sensor section is active and still consumes power unless power supply to the TV is cut off from the AC switch on the TV or the mains in the wall.

The same thing applies to a toaster also.

Again, plugging in an extension cord which has no load is same as keeping it unplugged so far as power consumption is concerned.

It is true that power is lost in long distance transmission. This fact, as you mention, could be misleading if not understood properly. Loss of power over long distance transmission implies difficulty in transporting current through metal cable, it does not mean that long cables consume power even without a load.

Transportation or transfer of current becomes less efficient with length because of the fact that resistance of metal increases with increase in length.

As such power is not consumed just by leaving a long extension cord which is in contact with AC power.

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