As the rise in price of energy and the impact of climate change, it has been shown that buildings play a huge role in being the largest energy consumer. Net Zero Energy Building (nZEB) is where a building has the ability to generate its own energy for its own use where the total amount of energy generated by the building by using renewable technologies is equal to the amount of energy use for the building thus making it net or nearly net zero energy building. The purpose of this study is to examine energy consumption in a retrofitted existing building, to investigate the economic impact of applying the net zero energy building concept on the retrofitted building and modeling a new net zero energy building for the same purpose that of the existing building. In this study, SketchUp is used in building the geometry of the building such as walls, windows and more while Openstudio is used to as a plugin in SketchUp to generate the file to be used in EnergyPlus. The EnergyPlus software has been used to identify the amount of energy use in the case building which amounted to 98 999 kWh annual site energy demand and 313 530 kWh annual source energy demand. The implementation of renewable energy for this study was solar and wind energy, where the amount of solar energy generated was to be 87 059 kWh and as for wind energy it was generated the amount of 5 653 kWh. With both energy generations, the net energy for the building was amounted to be 8 027 kWh that means by using the renewable technologies it generated 92% of the required building energy, and in terms of economics, the existing building annual electric bill is amounted to be MYR 23 165 while the retrofitted building is amounted to MYR 1 878.