Disaggregation of appliance usage from electrical meter data

The present invention provides a method for determining consumption of appliances within a surveyed household in which there are no sensors for measuring consumption of specific appliances. The method comprises - pre-processing historical consumption of appliances in a group of sampled household, based on measurements performed by sensors associated with said appliances, in relation to profiles of households, including characteristics of each household and/or lifestyle of the occupants and environmental time dependent parameters, - detecting presence of an appliance in a surveyed household based on correlations between the household profile and consumption patterns based on sampled measurement taken at predefined discrete time periods such 1 minutes, - detecting periodic activation in the surveyed household based on detection of presence of each appliance, identified correlations to household profile and consumption pattern and - estimating consumption of each appliance is the surveyed households based on detection of periodic activation of each appliance, identified correlations to households profile and consumption pattern.