Do laptop/cellphone charger's use energy when not plugged into hardware?

Question

Just wondering if my laptop and cell phone charger still use electricity when they are not plugged into the laptop/cellphone but still plugged into the wall.

Answer 1

Generally yes because these devices use ac power to drive a coil transformer, essentially this is an electromagnet that is always energized when plugged in which becomes waste energy in the form of heat and electromagnetic radiation,  The draw on these when not being used is small but it all adds up.  Using a power strip/surge protector with a toggle switch will allow you to stop the draw on these "wall warts".  Many new cell phone chargers are inductorless which allows them to draw even less power when plugged in but they still draw power.