As a part of global efforts to minimize reliance of fossil fuel and in order to minimize greenhouse gas emissions, smart buildings become a part of the solution as it is able to utilize real life events such as daylight, the usage of ambient air and it also is able to perform a head count and then adjust accordingly the heating ventilation and air conditioning HVAC system and the lighting system as well. Consequently this paper study and analyze the effect of building occupancy concentration on total electric demand. The case study was performed at Building 19 of Rockhampton campus of Central Queensland University using EnergyPlus simulation engine.