Determination Of Energy Consumption And Air Tightness Index Of Nearly Zero Energy Building Of Liaoning Province

With the development of building energy-saving technology,a perfect technical system has been formed.Ultra low energy buildings,nearly zero energy buildings and zero energy buildings have been pointed out and gradually realized.In recent years,according to the experience of European and American countries,China is gradually exploring the building energy-saving standard on the basis of national conditions.Referring to the successful cases of nearly zero energy buildings at home and abroad,the paper analyses the standard system of nearly zero energy buildings in Liaoning Province,including energy consumption index and air tightness index,to provide some guidance for building energy-saving work of the province.On the one hand,by summarizing the current residential and office building models in China,12 residential building models and 3 office building models are determined,and the annual heating/cooling demand of buildings is obtained by simulation with DeST software.Then,according to the calculation model in the standards,the primary energy consumption and utilization ratio of renewable energy are determined.On the other hand,the air tightness index N₅₀ is determined by referring to the domestic and foreign standards and the demonstration buildings in China.In addition,according to the basic principle of air infiltration,the calculation model of air infiltration under natural conditions is deduced and verified by experiments.So the main achievements of this paper are as follows.?1?Heat recovery of fresh air,solar heat gain coefficient?SHGC?and natural ventilation can significantly reduce building energy consumption,and the shading effect in different directions can be ranked as south>West>east.For residential buildings,the annual heating demand is less than 15kWh/?m²·a?,and the annual cooling demand is less than 9kWh/?m²·a?,and there are slight differences between different cities.For small office buildings,compared with reference buildings,the energy saving rate of near-zero energy consumption buildings is more than 15%.?2?For nearly zero energy buildings,lighting,domestic hot water and elevators are the main energy sources.It should be better to the use of high-efficiency energy-saving products.For residential buildings,the primary energy consumption is less than 55 kWh/?m²·a?and the utilization ratio of renewable energy is more than 30%.For office buildings,the energy saving rate of primary energy consumption is more than 45%,and the utilization ratio of renewable energy is more than 40%.?3?Based on the air permeability theory and LBL model,and the basic situation of residential buildings with high airtightness envelope in China,the air infiltration model under natural conditions is deduced,which is suitable for low-rise residential buildings,and the experimental verification of the model shows that the relative error is about 10%because of the measurement errors of meteorological parameters.Through energy consumption simulation and theoretical analysis,the energy consumption index and air tightness index suitable for nearly zero energy buildings in Liaoning Province are determined,and the air infiltration under natural conditions is supplemented,which provides a research basis for the formulation of future standards.