CCWI 2017 – Computing and Control for the Water Industry Sheffield 5 th - 7 th September 2017 Pumping Cost Optimization in Looped Water Networks with Storage Capacity through the Searching of the Setpoint Curve Christian-F. León-Celi 1 , Pedro Iglesias-Rey 2 , F. Javier Martinez-Solano 3 , D. A. Savic 4 , L. S. Vamvakeridou-Lyroudia 5 1,2,3 Department of hydraulic and environment. Politécnica de Valencia University, Valencia, 46022, Spain 4,5 Centre for Water Systems. University of Exeter. North Park Road Exeter EX4 4QF UK 2 Pedro Iglesias-Rey (piglesia@upv.es) ABSTRACT The pumping cost optimization still being a priority to minimize the operating costs in a water network due to the high cost of energy. In that context before to optimize the operation of installed pumps, it is required to find out the optimal operational points of each pump station independently of its associated features of flow rate and pumping head that are limited and limit the optimal solution. Thus, the aim of this work is to find the minimum energy curve (i.e. flow rate and pumping head) with the minimum cost that should be follow by each pump station to keep the minimum nodal pressure required by the network within a specific storage range in the tanks. This concept is known as setpoint curve. The objective function to be minimized considers the pumping cost with a diary structure of the energy fare, the water treatment costs and penalty costs related to the nodal pressure and the storage capacity of the network. To carry out the optimization the Differential Evolution algorithm has been applied. The proposed methodology has been tested in the water network D-town BWN II which has five pumping stations and seven tanks. Results show the maximum savings that it is possible to achieve in pump stations and gives important information to select a suitable pumping system that fit with the optimal operation of the network. Keywords: water, optimization, pump. 1 INTRODUCTION One of the priorities in decreasing operating costs in distribution networks is the minimization of costs of energy used to pump water. This can be done by a) diminishing either the discharge or the pumping head of the pump, b) enhancing the pumps efficiency, c) storing water in tanks at hours with low energy-fares, d) selecting the best pumping combination among the pumps installed, and d) by increasing the life of the pumps by means of the control of the starts and shutdowns of the pumps. Although some of these approaches usually are managed together most of the research works developed so far start with selecting the least-cost pumping combination. However, to achieve greater savings first it is needed to find the optimal discharge and minimum pumping head that each pumping station has to supply over the simulation period to meet the network requirements, which is the main aim of this work. In general terms, the lowest operating costs are associated with the least-cost pumping scheduling. This can be calculated either directly or indirectly. The direct approach tries to find when and how much time each pump must be working over the simulation period. On the other hand, the pumping schedule can be found as a function of other variables: least-cost pumping discharge (or pumping head) of each pump, and least-cost trajectory of tanks levels. Therefore, the decision variables can be the time, the flow rate, the pressure head or the levels of the tanks. To find theses variables