Iterative extended lexicographic goal programming method for fast and optimal pump scheduling in water distribution networks

Abstract

Pump scheduling in water distribution networks is important, especially nowadays with high energy prices . A good pump schedule is the one that reduces pumps’ energy and maintenance cost without worsening the overall system performance. Due to the nonlinearity of the hydraulic energy balance equations and complexity of water distribution networks, pump scheduling problem cannot be easily solved by hand, especially in the general case of a network with multiple tanks and pumps / pumping stations. A number of approaches exist in the literature addressing the trade-off between effectiveness (i.e. optimality of schedules generated) and computational efficiency but there seems to be no ideal solution. In this research, an effective and efficient optimization method named as iterative Extended Lexicographic Goal Programming (iELGP) is developed to solve a least cost pump scheduling problem. The method is tested on two multi-tank networks. The results obtained demonstrate that using the iELGP method an optimal pump schedule can be obtained with high computational efficiency which makes the method suitable for real-time application.