Application of nature inspired optimization algorithms in optimum positioning of pump-as-turbines in water distribution networks

In these days, energy, water, fossil fuel restrictions and greenhouse gas emission have become the mutual problem of all countries. The application of hydro turbines, especially pumps as turbines in water distribution network, can be a great solution to these problems. In this research study, it is aimed to introduce a procedure for obtaining the optimum position of a pump as turbine in water distribution network. For this purpose, two objective functions are considered, namely power and up surge ratio. The reason of selecting the power is to maximize the energy production and minimize the payback period, and the reason of selecting the upsurge ratio is to minimize the initial costs and network risks. In the proposed methodology, a transient analysis database is being combined with optimization algorithms. In this research study, Bently hammer software has been used for generating the mentioned database. Ant colony optimization algorithm has been used for obtaining the discrete variable and three other heuristic algorithms, namely grey wolf optimizer, whale optimization algorithm and ion motion algorithm were used for finding the best continuous variable. Pipe number and the position of hydro turbine on the pipe were considered as the discrete and continuous variables, respectively. The proposed methodology was tested on a network in Palermo which data were available. The results indicated that the proposed methodology can suggest the best 6 pipes among 70 pipes of network and also the accurate position of the turbine on the pipe.