Trade-off analysis between cost and reliability of water distribution systems using genetic algorithms

Abstract

In this paper, the trade-offs between the cost and capacity reliability of a WDS are investigated based on a multi-objective genetic algorithm formulation. The surplus power factor s (s factor) is used as the capacity reliability indicator. Two case studies have been investigated. For both case studies, the optimisation results show that there are significant trade-offs between cost and capacity reliability represented using the s factor. The s factor is also compared with the resilience index developed by Todini (2000). A comparison of results shows a positive relationship between the s factor and the resilience index, which confirms the feasibility of the s factor being used as an indicator of capacity reliability. In addition, as the calculation of the s factor does not require the head at the outlet of the network, which is required by most other reliability measures, the s factor can potentially be used to characterise the capacity reliability of a hydraulic system that delivers water to a tank or reservoir. © 2010 Taylor & Francis Group, London.