Evaluation of a Direct Drive Motor as Generator Driven by Centrifugal Pump as Turbine Energy Harvester for Rural Water Distribution Pipelines

Various turbine and generator technologies are utilized to harness energy. This study develops an in-pipe hydro-generator system using a modified direct drive motor as generator driven by pump as turbine (PAT). It targets to serve rural communities with water distribution pipelines. The direct drive motor is modified by rewiring the stator coils with a different size of wire and reconfiguring its connection. The selected PAT is a 76.2 mm by 76.2 mm (3 inch by 3 inch) centrifugal pump. Three initial pressure setups, i.e., 5, 10, and 15 psi, based on the common pressure range of rural water supply in the Philippines, are used in evaluating the in-pipe hydro system. The behavior of the system at varying load resistances is characterized in terms of the output voltage, current, power, voltage regulation, rotational speed, frequency, pressure, and flow rate. A maximum power of 341 W was generated at 8.5 psi. It was observed that generated voltage, current, and power are greater at higher water pressure. Rotational speed and frequency of the system, along with water pressure and flow rate, are observed to vary directly with load resistance.