A self-powered multiparametric sensor and valve for water distribution networks

This study presents the design, development, and experimental validation of a novel self-powered, multiparametric sensor and valve, named SWAMM, at the service of water distribution networks. The device integrates a miniaturized Cross-Flow type turbine (nano PRS type) with a built-in electrical generator, enabling energy harvesting directly from the pressurized water flow. In addition to autonomous power supply and continuous monitoring of the flow rate, SWAMM offers hydraulic regulation by means of a mobile slider mechanism. To maintain optimal turbine efficiency and reduce the volume error across variable flow rates, a flow-adaptive control strategy has been developed, supported by two polynomial functions: a quadratic law linking the flow rate with the pressure drop before the rotor, and a cubic law linking the flow rate with the head loss along the turbine. The coefficients of these functions were experimentally calibrated through laboratory testing. The SWAMM prototype was tested under controlled hydraulic conditions simulating real network operation, with flow rates ranging from 0 to 6 L/s. Results demonstrated that the device can produce up to 100 W of electrical power, with a nominal output of approximately 50 W at 2 L/s, and can operate efficiently even under partial flow conditions. Volume measurement error, assessed according to the MID European Directive, confirmed accuracy within acceptable thresholds. The harvested energy is sufficient to power also onboard electronics, communication modules (LoRaWAN), and auxiliary sensors. SWAMM sensor represents a significant advancement in smart metering, enabling both monitoring and control functions without the need of any external energy source.