Direct control of residential water heater loads to reduce power system distribution losses

This paper presents a new method to reduce the real power losses and increase the associated dollar savings in electric power distribution systems. The method is based on the direct control and management of the power and energy consumption of residential water heaters. The objective function includes, among others, the cost of real power losses, the cost of the annual energy losses, and the cost associated with purchasing and installing additional water heating storage capacity at customer locations. Using a number of constraints, the objective function is solved and the optimal number and location of water heaters on a distribution feeder are determined. Through this procedure, the total system costs are minimized and the dollar savings are maximized. Details of the optimization procedure and some practical results are presented.