Feasibility of low-cost energy management system using embedded optimization for PV and battery storage assisted residential buildings

Abstract

In this study, an energy management system (EMS) focusing on low-cost hardware and embedded optimization has been built. A benchmark consisting of a residential photovoltaic (PV) and battery connected to the grid but without feed in power has been considered. The proposed EMS accepts input variables as building electrical load data, PV output data, the electricity time of use rates. The master EMS ensures the optimization of the battery charge-discharge profile to reach the lowest possible energy bill. Sensitivity analysis demonstrates that the presence of optimization systems leads to a more stable energy cost even though power demand and PV production vary during the day. In the cases studied, the bill reduction is 32% up to 50% depending on load or solar PV generation variations. By comparison, in the literature where more complex optimization in MATLAB environment were used, a bill reduction of 24%–34% was realized. The system cost is estimated to be around 30$ which is much lower than the typical 100$-600$ price for similar products. The system can be practically integrated in applications such as EMS of schools, residential or public buildings by inserting it through the power distribution panel where all protection devices are located.