Part of the show Naked Scientists Question and Answer Show
We're using electric chargers to charge phones, torches and things. Once the product is charged does the charger switch off or does it carry on using the same amount of electricity until you switch it off.
They will carry on using some electricity but it will be significantly less than it would be using whilst you were charging the phone or whatever. They're not made perfectly and if you don't draw any current they still use some just to heat themselves up and you get losses in places, its quite small maybe less than a fifth of a watt.