yeah but is that your jobbie?
It does form part of my job, yes
well then wrap one of them round your mains cable into the house and let the fun begin.....
well I suppose it depends on how much detail you want. Most manufacturers can provide details of power levels in high flow and quiescent currents. And to make that a comprehensive thing would require a monitor on each device, or possibly each ring main etc.
Okay it's always worth demoing something for the kids. It might create an interest and such like for them. But mine looked at one for a few seconds and then some months later it got binned. that was a free one from the electricity company. the free light bulbs have been useful.
So if you can get one free, and you usually can by asking about.
I would invest the funds in motion sensor lighting.