Performance Analysis and Optimal Operational Planning of Water Supply Systems

Abstract

From the viewpoints of energy and cost savings, it is important to rationally operate water supply systems composed of pumps, piping, and reservoirs. However, it is very difficult, because nonlinear performance characteristics of pumps and piping, discrete performance characteristics due to the combination for on/off status of pumps, and daily operational strategies of reservoirs must be considered. In this paper, a two-stage approach to the performance analysis and optimal operational planning of a water supply system is proposed. At the first stage, the performance characteristics of pumps and piping are analyzed by the Newton-Raphson method, and are optimized with respect to the combination for on/off status and revolution speed ratios of pumps by the enumeration and nonlinear programming methods, respectively. At the second stage, the daily operational strategy of the system is optimized with respect to the storage level of a reservoir by the dynamic programming method. A case study is conducted to show the effectiveness of this approach.