A two-tier energy management system for smart electric vehicle charging in UCLA: A Solar-To-Vehicle (S2V) case study

Integration of Electric Vehicles (EV) and Renewable Energy Sources (RES) with Energy Management System (EMS) in microgrid has been widely discussed. In this paper, we present a two-tier EMS system currently in operation on campus of University of California, Los Angeles. The upper level system, called Super Control Center (SCC), processes grid-wide energy coordination while the lower level systems manage local EV charging and other micro-scale services. We use the concept of Solar-to-Vehicle (S2V) to demonstrate the combined function of the EMS system. For lower level system, we present two queuing algorithms with user priority calculated from user's Solar-Friendliness Index (SFI), i.e., solar composition of user's energy consumption profile. The algorithms have shown capabilities to increase RES utilization, while actively encouraging users to change consumption behavior and promoting higher RES utilization. Simulation results have shown that SCC can reduce up to 73% of the EV load. The lower level EV coordination algorithms are able to increase the RES utilization from 0.504 to 1.