Smart Day-ahead Pump Scheduling Scheme for Electricity Cost Optimization in a Sewage Treatment Plant

In this paper, we propose a smart coordination scheme of a pump system in the sewage treatment plant. The task is to find an optimal day-ahead joint schedule of multiple pumps in terms of minimizing the electricity cost, while complying system restrictions such as the water level at a sewage tank. The mixed-integer linear programming is used for optimizing the objective function jointly considering pump specifications, system restrictions, and times of use electricity prices. We evaluate the proposed method by simulating the pump system based on captured time-series states of the pumps and environments from an actual sewage treatment plant. In numerical evaluations, the proposed scheme provides up to 11.5% potential electricity cost savings compared to the run without such coordination for pumping the same volume of the sewage.