Methodology for Detecting Critical Points in Pressurized Irrigation Networks with Multiple Water Supply Points

The modernization processes of hydraulic infrastructures from old open channels to pressurized networks have increased water use efficiency along with a dramatic increase of energy consumptions. The significant energy requirements associated with the increment of the energy tariffs for irrigation involve higher production costs for farmers. Therefore, strategies to reduce energy consumption in irrigation districts are strongly demanded. Methodologies based on sectoring and critical points control have been applied to branched networks with a single water supply point, obtaining significant energy savings. In this work, a new critical point control methodology for networks with multiple sources has been developed: the WEPCM algorithm, which uses the NSGA-II multi-objective evolutionary algorithm to find the lowest energy consumption operation rule of a set of pumping stations connected to an irrigation network that satisfies the pressure requirements, when the critical points are successively disabled. WECPM has been applied to a real irrigation district in Southern Spain. The obtained results were compared with those achieved by the WEBSOM algorithm, developed for sectoring multiple source networks. The control of critical points by the replacement of two pipes and the installation of four booster pumps provided annual energy savings of 36 % compared to the current network operation. Moreover, the control of critical points was more effective than sectoring, obtaining an additional annual energy saving of 10 %.