A power control system that includes a plurality of electrical appliances and a controller. Each of the electrical appliances includes an energy storage device comprising a heat storage medium, a heater, and a temperature sensor. The heater is configured to heat the storage medium at a heating rate. The temperature sensor produces a temperature signal that is indicative of a temperature of the heat storage medium. The controller adjusts the heating rate of each energy storage device from a first heating rate to a second heating rate based on the temperatures of the heat storage mediums of the other energy storage devices.