Development and validation of a residential water heater simulation model

A general simulation model for a residential water heater has been developed and tested against detailed field test data. The validated model is capable of predictions of hourly average electrical demand patterns. The time average dynamic behavior of the water heater electrical element operation is simulated by the use of two zones of varying size, with a moving interface between them as a consequence of water draw, and a third zone of nominally fixed dimension. Additional space discretizations are used to model the preheat portion of the water heater in solar and solar/load management configurations. The model structure attempts to deal with the effects of tank stratification, heating element control dead band and interlock of the heating elements.