Assessment of Pump’s Performance in Water Supply Systems – Data Collected From Multiple Case Studies

Abstract

This paper reports the evaluation of pump's efficiencies and its optimization potential, in three water supply systems. The study surveyed 65 pumps groups, from 24 pumping stations, between 5 to 350 kW of absorbed power, with flow rates from 25 to 1500 m3/h. The performance of the pumps, was assessed by testing each pump group in different operational conditions. It was quantified, for each pump group, the specific consumption (kWh/m3) and cost (€/m3) as well as the difference between the optimum efficiency point, for the specific net head of each installation, and their actual operating point. The identified energy inefficiencies and proposed corrective measures for each pump group were compiled in order to improve their efficiency. Most problems identified are oversized groups, valve problems and inadequate operational working points. On average the surveyed pump's efficiencies were 10 percentage points below their reference values. In order to reduce the gap several improvement measures were proposed, such as the refurbishment of the pumps, impeller adjustments, variable speed drive installation and the extension of the working periods with lower frequency regimes, where high efficiencies were identified. The implementation of these improvement measures has an energy saving potential of 331 MWh/year, which means 27.000 €/year.

Water–Energy Nexus in Typical Industrial Water Circuits

“…The potential savings for reduction in energy consumption for each sector and country were determined by applying the achieved shares of energy savings as a factor on the electricity consumption of each sector and country, according to Equation (8), in which ε designates the achieved share of energy savings.…”

“…The electric motors account for a considerable share of the total energy consumption in industry. As mentioned above, it is claimed that pumping systems account for about 20% of the total electricity demand in the world [8]. In the European Union, motor-driven systems are reported to correspond for 65% of the total electricity consumption [40].…”

“…The levels of average electricity consumption in German manufacturing industry are more significant compared to other Member States, such as Portugal, as well as to the average levels of the European Union, as observed Figure 2. The potentials for reduction in energy consumption for each sector and country were determined by applying a share of energy savings, attending to Equation (8).…”

Corrosion Prevention on S45c Using Hardening Method

“…Pumps have been widely used in almost all industrial fields, such as in cooling, heating, lubrication, hydraulic processes, and water transportation. In its use, however, it is crucial to pay attention to the pumping system as it uses up to 25-50% of energy in an industry (Cardoso et al, 2017). During the pumping operation, the pump shaft is constantly degraded by corrosion or mechanical degradation.…”