Excess Pressure in Municipal Water Supply Systems as a Renewable Energy Source: Antalya Case Study

Abstract

Pressure management is one of the most effective methods for water loss reduction. Pump used in turbine mode (pump as turbine, PAT) is a viable option for reducing excess water pressure, water losses, and pipe failures in water distribution networks in addition to energy production at microscale. In this study, a PAT system recently installed in Antalya City of Turkey is presented, and its performance is evaluated for its initial operational period of approximately 5 months. This full-scale PAT system was implemented in a parallel pipeline with a pressure-reducing valve (PRV). The operation of the PAT system was continuously monitored online for flow rate, power, and pressure levels. The PAT system proved to work efficiently in a wide range of inflows (130–300 m3/h) where the produced energy varied between 0.7 and 8.4 kWh for a reduction of approximately 1 bar pressure head with an average efficiency of 60%. Environmental benefits of green energy production, reduction in physical water losses, and carbon dioxide emissions were evaluated. The payback period of the PAT application was computed as 53 days based on the costs and revenues of the PAT application.