I'm sure that makes sense to you in connection with an energy meter.
Does it tell you if your flat mate is using the grill? Does it tell you when he leaves it on when you're out? You spend all your time at home staring at an energy meter? Is that before or after that bottle of whisky?
Ah. I really must get an energy meter, To tell others how much a phone costs to charge.
Most electrical devices state their power consumption. But obviously something else of the many things you don't understand.
Ah. Right. You want one to rip off a lodger. Say no more.