Influence of outdoor air on energy consumption of residential buildings with passivhaus technology

The high demand of passivhaus technology for building envelope improves the insulation property and air tightness, which effectively decreases the cold or heat loss caused by thermal conductivity and air infiltration. However, in order to meet the requirement of indoor sanitation and thermal comfort, ventilation and air conditioning are necessary, thus the energy consumption of air handling and distribution is more prominent. Based on the differences between passivhaus standard and domestic relevant design standard for energy efficiency of residential buildings, builds the different models for comparison. Performs simulation and contrastive analysis about cooling and heating load, as well as energy consumption of ventilation and air conditioning systems under different levels of outdoor air in residential buildings in Beijing. The results show that when the minimum outdoor air volume is 30 m³/(person·h), the maximum heat load of passivhaus standard model is 22 W/m², and the maximum cooling load is about 55 W/ m², where the outdoor air load can occupy 63.8% and 34.2% in winter and summer, respectively. A certain degree of energy utilization efficiency can be obtained by using mechanical ventilation and energy recovery devices. Then the heating and cooling energy consumption of passivhaus standard model can be 22.66 kW·h/（m²·a）, which saves energy by about 7% than the model with Design standard for energy efficiency of residential buildings.