The influence of a variable volume water heater on the domestic load profile

In this paper a variable volume water heater and a load impact model is presented. The variable volume water heater is a unique system that can be implemented as a residential demand-side management tool. The variable volume water heater can shift the electrical energy consumption, used to heat water, to off-peak time periods. The electrical energy is shifted without influencing the hot water usage of the customer. The load impact model simulates the effect of controlling the volume of stored hot water on a domestic load. The model mathematics as well as the model verification are discussed. The paper ends with a comparative case study on two residential areas. The case study indicates that the variable volume water heater can reduce the system peak as well as increase the off-peak energy consumption.