Research Article Assessment of Electrical Load in Water Distribution Systems Using Representative Load Profiles-Based Method Gheorghe Grigoras Power System Department, Electrical Engineering Faculty, “Gheorghe Asachi” Technical University of Iasi, Boulevard Dimitrie Mangeron, No. 21-23, 700050 Iasi, Romania Correspondence should be addressed to Gheorghe Grigoras; ghgrigoras@yahoo.com Received 17 April 2014; Accepted 28 June 2014; Published 21 July 2014 Academic Editor: Mamun B. Ibne Reaz Copyright © 2014 Gheorghe Grigoras. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Te problem of optimal management of a water distribution system includes the determination of the operation regime for each hydrophore station. Te optimal operation of a water distribution system means a maximum attention to assess the demands of the water, with minimum electrical energy consumption. Te analysis of load profles corresponding to a water distribution system can be the frst step that water companies must make to assess the electrical energy consumption. Tis 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. Te proposed method is tested on a real urban water distribution system, showing its efectiveness in obtaining the electrical energy consumption with a relatively low computational burden. 1. Introduction Water and energy are critical resources that afect virtually all aspects of daily life. A huge amount of electrical energy is necessary for the transportation, treatment, and distri- bution of water for drinking and industrial consumption and for diferent 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 process while 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]. Te energy requirements vary signifcantly from city to city, depending on local factors such as topography, location and quality of water sources, pipe dimensions and confgurations, treatment standards required, and the types and numbers of consumers [1–8]. Water industry decisions on operational strategies and technology selection can also signifcantly infuence electrical energy consumption [5]. A high electrical energy consumption may be due to various reasons: inefcient pump stations, poor design, installation or maintenance, old pipes with high head loss, bottlenecks in the supply networks, excessive supply pressure, or inefcient operation strategies of various supply facilities [2–4, 9–16]. Energy-saving measures in water supply systems can be realized in many ways, from decreasing the volume of water pumps (e.g., adjusting pressure zone boundaries) to reducing the price of energy (e.g., avoiding peak hour pumping and making efective use of storage tanks) or increasing the efciency of pumps (e.g., ensuring that pumps are operating near their best efciency point). Tese energy- saving measures ofen pay for themselves in months, most do so within a year, and almost all recover their costs within three years. Prolonging this enactment period would increase the investment required for long-term [11–16]. Utilities can further reduce energy costs by implementing on-line telemetry and control systems (SCADA) and by managing their energy consumption more efectively and improving overall operations from water supply systems [2]. Te motivation for introducing such systems is due to the following factors [2, 9–15]: (i) operation of water supply systems which is in many cases becoming more complex, with rising demands, Hindawi Publishing Corporation Advances in Electrical Engineering Volume 2014, Article ID 865621, 10 pages http://dx.doi.org/10.1155/2014/865621