AWWA CSC92075

One of the benefits of Supervisory Control and Data Acquisition systems (SCADA) for water system monitoring and control is reducing power costs by the use of off-peak, or time-of-use (TOU) power. Although this potential benefit is usually cited, there is generally no attempt made to show how to reach the goal of lower power bills. This paper will describe the TOU operational philosophy used by California Water Service Company (CWS) and illustrate how it was integrated into several SCADA systems. Example flowcharts will be presented so that the do-it-yourself SCADA system programmer can see how one agency implemented TOU control. The algorithms presented here are also useful when entering operational strategies into "canned" SCADA software.