Page 7 - Demo

472N. Amani, A.A. Reza Soroushuse intensity would be equal to 80.4 kWh/m2/y. The building orientation does not change relative to the previous model (base model) and is based on the geographical north. The ratio of windows to the northern and southern walls is 40% by default. These windows have shades as high as 2/3 of the window height. Also, the type of these windows in the conceptual model is triple-glazed windows with low emission. The eastern and western windows have been removed from the conceptual model due to the lack of efficiency. The walls structure in the conceptual model is according to Table 4, and the roof structure is lightweight and without insulation. The value of the building infiltration rate is 0.17 ACH. The value of the lighting efficiency parameter is assumed to be 3.23 W/m2. The values of the plug load efficiency and the operating schedule are adjusted according to the BIM parameter. The building%u2019s HVAC system is assumed to be a high-efficiency variable air volume system. Also, the building has a daylighting and occupancy control system. To achieve the highest level of energy efficiency, the photovoltaic solar panels were used with a yield of 20.4% and surface coverage of 90%. The payback limit of these panels are set at 30 years. Results of this analysis show that the use of BIM technology for adjusting the parameters affecting energy consumption in the conceptual designs can save up to 57.43% energy cost. Based on the energy use intensity, this value would be 28.85%. Baseline energy model specifications Depending on analysis tools and specific studies, the building energy model requires a set of parameters. Table 5 shows the basic parameters of the building%u2019s energy model as the basis of design. These parameters include: material constructions of building elements and associated thermal properties, HVAC and hot water system types and efficiencies, lighting density and efficiency, building occupancy, plug loads (appliances and electronic devices), internal heat gains from plug loads and occupancy, building natural infiltration rate (air leakage), natural ventilation (the opening and closing of doors and windows), thermostat set-point temperatures, and operating schedules. These parameters are specified Table 4: Optimization of the parameters effecting energy in the conceptual massesBuilding form Module-1 Module-2 Module-3Energy cost (USD/m2/y) 5.96 7.69 7.18Effective factor Input parameterBuilding orientation BIMWindow-to-Wall ratio (Southern walls) BIM (40%)Window shades (south) 2/3 Win HeightWindow glass (south) Trp LoEWindow-to-Wall ratio (Northern walls) BIM (40%)Window shades (north) 2/3 Win HeightWindow glass (north) Trp LoEWindow-to-Wall Ratio (Western walls) (0%)Window shades (west) BIM (No Shade)Window glass (west) BIM (No Window)Window-to-Wall ratio (Eastern walls) (0%)Window shades (East) BIM (No Shade)Window glass (East) BIM (No Window)Wall construction R13+R10 MetalRoof construction BIM (Lightweight Construction %u2013 No Insulation)Infiltration 0.17 ACHLighting efficiency 3.23 W/m2Daylighting and occupancy controls Daylighting and Occupancy ControlsPlug load efficiency BIM (10.76 W/m2)HVAC High Eff. VAVOperating schedule BIM (24 Hours)PV - panel efficiency 20.4%PV - payback limit 30PV - surface coverage 90%Table 4: Optimization of the parameters effecting energy in the conceptual masses