The problem of optimal management of a water distribution system includes the determination of the operation regime for each hydrophore station. The optimal operation of a water distribution system means a maximum attention to assess the demands of the water, with minimum electrical energy consumption. The analysis of load profiles corresponding to a water distribution system can be the first step that water companies must make to assess the electrical energy consumption. This paper presents a new method to assess the electrical load in water distribution systems, taking into account the time-dependent evolution of loads from the hydrophore stations. The proposed method is tested on a real urban water distribution system, showing its effectiveness in obtaining the electrical energy consumption with a relatively low computational burden. 1. Introduction Water and energy are critical resources that affect virtually all aspects of daily life. A huge amount of electrical energy is necessary for the transportation, treatment, and distribution of water for drinking and industrial consumption and for different internal technological processes of water distribution systems. Water distribution systems are massive consumers of energy, which is consumed in each of the stages of the water production and supply chain: starting from pumping the water to the water treatment plant, followed by the treatment processwhile distributing the water via the network. In the Report Watergy by Alliance to Save Energy, it has been asserted that 2-3% of the world’s electrical energy consumption is used to pump and treat water for civil and industrial supply [1]. Energy costs constitute the largest expenditure for nearly all water utilities worldwide and can consume up to 65 percent of a water utility’s annual operating budget [2]. The energy requirements vary significantly from city to city, depending on local factors such as topography, location and quality of water sources, pipe dimensions and configurations, treatment standards required, and the types and numbers of consumers [1–8]. Water industry decisions on operational strategies and technology selection can also significantly influence electrical energy consumption [5]. A high electrical energy consumption may be due to various reasons: inefficient pump stations, poor design, installation or maintenance, old pipes with high head loss, bottlenecks in the supply networks, excessive supply pressure, or inefficient operation strategies of various supply facilities [2–4, 9–16]. Energy-saving measures in water supply systems can
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