A power metering system includes any number of sites and a central database. Loads within a site are unmetered and a sensor data vector over time includes sensor data, operational data and external data. Iteration occurs over time intervals for all unmetered loads and the unmeasured power for each interval is disaggregated by matching a load type with a computer model in the central database having the same feature domain in order to predict the power usage of each load. Iteration again occurs over those intervals in which only a single load is operating; the power of that load is determined to be the unmeasured power minus miscellaneous power, and a new computer model is fitted for that single load and also uploaded to the database. The feature domain of an existing model may also be increased. Both iteration steps repeat until no more unmeasured power can be disaggregated.