Real time control of a prototype for pressure regulation and energy production in Water Distribution Networks

In recent years, the opportunity of coupling a pressure management strategy with power generation in water distribution networks (WDNs) has attracted increasing interest. Numerical simulations developed for a number of real cases showed attractive profits and capital payback periods. Although many micro- and pico-hydro plants currently are operating along supply water mains, installations in WDNs are quite uncommon because of the high variability of flow and pressure patterns. Aiming at robust and effective industrial-based solutions, a laboratory prototype was developed for hydropower generation in WDNs. A pump as turbine (PAT) was used for generation, although a traditional turbine could be used as well. A control strategy was developed and implemented for automatic setting of regulating valves, aimed at both ensuring adequate pressure over the network and maximizing electric power. Experiments showed that the valves, equipped with the automatic control system previously described, can automatically both regulate the flow running the PAT and guarantee the set point pressure at the network monitored node, even in cases of abrupt change in pressure and flow discharge.