# Calculate Facility Total Building Electric Demand Power

Hi everyone,

I am modeling an Room model that has ElectricEquipment:ITE:AirCooled as an IT Equipment and I modified it like below:

ElectricEquipment:ITE:AirCooled,
WestDataCenter_Equip,    !- Name
West Zone,               !- Zone Name
FlowFromSystem,          !- Air Flow Calculation Method
Watts/Area,              !- Design Power Input Calculation Method
,                        !- Watts per Unit {W}
,                        !- Number of Units
180,                     !- Watts per Zone Floor Area {W/m2}


My area is about 167m2 so when I use Output Facility Total Building Electric Demand Power to see the IT power in my model it approximately 47.9 kW instead of 30kW (= 180W*167m2) average per hour. This is my model.

Can someone tell me that where is different 17.9 kW (= 47.9 - 30) between 2 values? Or how we can calculate the Facility Total Building Electric Demand Power (and Facility Total HVAC Electric Demand Power) in EnergyPlus?