> To me, this reads like trying to predict the presence, make, model & operational schedule of someone's washing machine just by observing how fast their power

> To me, this reads like trying to predict the presence, make, model & operational schedule of someone's washing machine just by observing how fast their power meter spins over time. That sounds almost trivially easy provided you can afford to buy each and every washing machine on the market so you can measure its power consumption profile for each of its programs.