Optimizing pump operations in water distribution systems: energy cost, greenhouse gas emissions and water quality

In this study, a multiobjective optimization approach was adopted to optimize pumping operations by minimizing energy cost and greenhouse gas (GHG) emissions while considering water quality either as an additional objective or as a constraint. When water quality was not included, a trade-off between energy cost and GHG was found. Including water quality as a constraint led to an overall increase in energy cost and GHG emissions while keeping trade-offs between the objectives. When water quality was included as a third objective, there was a positive correlation between energy cost and GHG emissions, but a negative correlation was found between water quality and the other two quantities (energy cost and GHG). The three-objective formulation enabled a deeper understanding of each individual solution, while also providing a wider range of possible alternatives to consider.