Leakage Control and Energy Recovery Using Variable Speed Pumps as Turbines

Abstract

One of the primary concerns in water supply systems is pressure control. High pressure increases both leakage and the risk of pipes bursting, while low pressure can reduce the water supplied to consumers and allow the intrusion of pathogens. Therefore, the operation of the equipment must be optimized to avoid such problems. In high pressure zones, pressure reducing valves (PRVs) are commonly used for pressure control. However, the energy dissipated from head loss could be recovered to produce electrical energy. The use of pumps as turbines (PAT) in this case is an alternative to improve the system efficiency. However, owing to the dynamic operation, PAT performance drops significantly during some periods of the day. The use of variable speeds can solve this problem, but the PAT selection to optimize the operation remains an issue. Therefore, this paper presents a method to simultaneously select PATs and schedule their operation using variable speed to improve energy recovery and reduce leakage. Two networks are studied and the performance in leakage control is compared with the PRV operation.