Techno-Economic Analysis and Battery Storage Placement in Grid-Connected Photovoltaic (PV) System

Abstract

Solar generation is a prominent source of renewable energy, especially for countries with an abundance of solar irradiance. In Singapore, a rooftop solar system has been deployed in shipyard to generate electricity from the highest irradiance which is in Tuas, West Region of Singapore. Due to declining cost of battery energy storage system (BESS), this industrial research study on the rooftop system focuses on the steady state stability of gridconnected photovoltaics (PV) system with BESS. A return on investment (ROI) from rooftop PV system is calculated and compared with its end of life (EOL), which shows that the payback on capital for this system is approximately 6 years. This system is then modelled in MATLAB to study the charging and discharging characteristics of the BESS when connected at different voltage levels. In addition, the power quality in the grid-connected PV system with BESS at varying state of charge is studied using a load flow analysis. The results show that the charging and discharging characteristics, as well as the power quality vary at different voltage levels and BESS’s state of charge.