A Study on LVDC Systems for Commercial Building Applications

Low Voltage Direct Current (LVDC) systems are an upcoming and evolving concept that integrates DC renewable sources such as solar PV and wind into a DC load system. The DC load system mainly consists of highly efficient LED lamps, BLDC fans, and modern electronics run on DC. This study examines a commercial LVDC nanogrid system. The commercial space taken under consideration is a single room, which operates from 9AM to 5PM on weekdays. It is then designed and simulated on HOMER (Hybrid Optimization Model for Multiple Energy Resources) Pro, first as a grid-connected LVDC system and then as an isolated LVDC system. They are then compared with the grid-connected AC system with both legacy and energy efficient AC loads and with or without battery backup and solar PV. Then the maximum critical load possible for the isolated system is determined using simulations.