Optimal Real-Time Operation of Urban Water Distribution Systems Using Reduced Models

Abstract

A method for near-optimal real-time on-line operation of urban water distribution system is presented and demonstrated. It uses a reduced model RM of the network which reproduces its performance over time with high fidelity with optimization by a genetic algorithm GA. The RM-GA software uses network data, forecasted demands for an operational planning time-horizon 24 h ahead, field data from a SCADA on the current status of the network, time-of-day energy cost data, and operator-imposed constraints on tank water levels and demand junctions pressures. The GA looks for the near-least-cost operation plan for the whole time horizon, using the reduced network model, and activates the first hour of the plan through the SCADA. At the end of the hour, the status of the network is updated from field data, the time horizon is rolled ahead by 1 h, and the process repeated. The software was developed for and demonstrated on the distribution system of Haifa. Experiments were conducted, in which the operation which simulates the operators' set-point operation is compared with that obtained by the RM-GA, and energy cost savings of 8 and 10% were calculated for a summer and winter month, respectively.