They say to unplug unused devices to save on electricity, but what if you just unplug the device from its power supply, and leave the power supply plugged into the wall outlet?
Does it still use electricity?

sussex electric

A fixed amount of voltage is being maintained at our power supply. But, if no one uses it, (I mean if no one in the whole of the electricity line consumes any voltage) then is it wasted?
In other way, if one city has power shortage and decide to not to use power for one day. Can it help to have sufficient power for other day.

sussex electrical