for me, the first priority is to keep track of the meter status. Therefore I persist this value only for historic reasons.
then I persist the actual power consumption for the use in HABPanel charts, so I can easily get a feeling on how we use power throughout the day.
What I do additionally is to find a solution to Monitor specific device consumptions, like the washing machine or dishwasher. Use case here is to find out, whether the program is ready (I don’t want to open the machines to get the “ready”-voltage on the respected led). There’s a pretty sophisticated thread on this:
I don’t think, you could read 100% precise washing machine state in the overall consumption of your home. just today, I received my “Sonoff POW”, and trying figuring out, how to use it: