The building sector is the largest consumer of the primary sources of energy worldwide. The most commonly used primary sources of energy to generate electricity are oil, coal, peat, shale, natural gas, nuclear, hydro, renewables, biofuels, and waste. The energy demand by the building sector is about 40% of the world’s energy production.Net Zero Energy Buildings (NZEBs) is the best solution recommended by the energy experts to reduce substantial pressure on primary sources of energy contributed by the building sector. There is a marginal gap between estimates made during the design stage and actual energy performance of residential buildings, primarily due to a lack of understanding of the factors affecting energy use and whole building simulations software limitations. The purpose of this research work was to conduct a comparative analysis of a predicted versus actual energy consumption of prototype Net Zero Energy Building (NZEB) constructed at Higher College of Technology, Muscat. Hourly Analysis Program (HAP V4.2) was used to predict energy demand of NZEB at HCT and same size regular house in Muscat. PVWatts calculator was used to determining possible power generation by the PV system installed on the roof in the form of a canopy. The constructed house was tested for one month to perform multiple tasks as per competition requirements in which one of the major tasks was to produce onsite energy production by PV panel’s equivalent to the energy consumed by the house. The actual energy consumption results were compared with the simulated result and observed that actual energy demand of house was approximately 20% lower than that predicted by the simulation tool. The comparison of simulation results between NZEB and regular house indicated 61.24 % less energy demand of NZEB, mainly due to less HVAC load. The simulation result for BEI of NZEB showed 87.20 kWh/m2/year as compare to 225.1 kWh/m2/year for same size regular house. The simulated result obtained from PVWatts calculator for competition period and actual production of an installed PV system at the top roof showed a minor deviation of 0.73% only. It is also observed from the results during the competition period house exported 1221 kWh energy to the grid.