# Software for Monitoring the In-Service Efficiency of Hydraulic Pumps
## 1 Introduction  
Water and energy are two vital sources of any urban community's daily life. In the United States, 19% of all the energy produced is consumed for the supply of drinking water, including treatment, transportation, storage, distribution, collecting of sewage water, treatment and discharge [1]. The situation is almost the same in the European Union, where 22% of the total electricity consumption of the industrial systems fitted with electric engines runs the pumps; the annual electricity consumption was 109 TWh in 2005 for water pumping, and in 2020, the increase in energy consumption was 136 TWh, a growth of 25% [2]. The life cycle cost of centrifugal pumps installed in industrial applications consists mainly of maintenance and energy costs. The energy cost is the most significant contribution in the total life cycle cost of a pump [3, 4]. Depending on the industry in which the centrifugal pumps are installed, the total life-cycle cost comes from the consumption of electric power (e.g., chemical industry 26%, pulp and paper 31%, petroleum 59%, water treatment and supply systems from 55% to 90%) [5]. Proper selection of the pump in correlation with the system requirements can reduce energy costs by an average of 20%. This means that the pump operates mostly with maximum efficiency in the vicinity of the best efficiency point (BEP). In contrast, the hydraulic pumps that operate at off-design conditions lead to premature damage, wasted costs andcostly repairs or replacements [6]. All these issues can be avoided by selecting the appropriate pump, monitoring it and providing well-planned maintenance [7]. This applies to all situations involving the operation of pumps and particularly in cases where an adequate monitoring system is missing. Once the pump is installed, its efficiency is determined by the process conditions. The major factors affecting performance include the efficiency of the pump and system components, overall system design, efficient pump control and appropriate maintenance cycles. To achieve the efficiencies available from the mechanical design, pump manufacturers must work closely with end users and design engineers to consider all of these factors when specifying pumps [8]. The only parameters that are neither determined nor examined are the pump and pumping station efficiencies, although all the other variables (absorbed power, pumping head) are measured to determine and calculate these parameters. Energy savings represent lower operating costs and higher performance. The most obvious energy savings are those associated with improvements in pump efficiency [9]. Although worth pursuing, they are small compared to the efficiency gains that can be achieved through a proper analysis of the pumping system to obtain the best fit of the pump to the system and the operating requirements. It may be comforting to select the nominal flow rate (at the highest value of the flow rate). However, the energy penalty can be significant when the pump is operating at partial flow rates. A correctly selected maximum flow rate is a key value where energy optimization is targeted. Most pumps run far from their BEP. For reasons ranging from short-sighted or overly conservative design, specification and procurement to decades of incremental changes in operating conditions, pipes and control valves are too large or too small. In anticipation of future load growth, the end user, supplier and design engineers routinely add 10-50% safety margins to ensure the pump and motor can accommodate anticipated capacity increases. Important energy savings can be made if the safety margins imposed to obtain the rated service condition are not excessive [3]. The average pumping accounted for 80% of total electricity use in public water systems, as reported by EPRI [5]. The use of electricity for water and wastewater treatment has grown during the last 20 years and will continue to grow. The efficiency of the pump affects the pumping performance significantly.