Pumps as turbines regulation study through a decision-support algorithm

The water distribution network (WDN) is subject to water leakages due to pipes breaking, which induces a wastage of water and overconsumption of power for pumps. Leakages are directly related to pressure in the pipes. To reduce leakages, pressure reducing valves (PRV) are installed in water distribution networks to reduce pressure in the pipes. However, pressure reduction induces a loss of energy which is wasted within the PRV. To recover a part of this energy, pressure reducing valves can be replaced by using pumps as turbines (PATs). Since head and flow rates are variable in the WDN, it is necessary to regulate the PAT, which does not function properly under variable upstream conditions. In this paper, the hydraulic regulation (HR) and hydraulic-electric regulation (HER) methods are studied in economic and energy production terms. A comparison between HR and HER is based on results from two real sites. The study is carried out using an innovative decision-support algorithm, which is described in detail. The results show that adding electrical regulation improves energy production, but the increase in installation costs makes the sites less economically viable.