Study on fresh air load characteristics and energy saving measures of low energy consumption buildings in severe cold area

Abstract

In order to study the fresh air load characteristics of low energy consumption buildings with different envelope structure parameters, combined with the law of fresh air load, energy saving measures were studied. Taking the ultra-low energy consumption building of Shenyang Jianzhu University as an example, the DeST simulation software was used to establish five groups of models with different envelope structure parameters for load simulation. The simulation results show that the fresh air heat load in model 1 to model 5 is 29.89%, 34.66%, 38.60%, 44.68% and 53.36% of the building heat load, respectively. The seasonal fresh air cooling load of air conditioning accounted for 13.78%, 13.85%, 13.88%, 13.99% and 14.05% of the building cooling load respectively. The thermal insulation performance of the envelope has great influence on the thermal load of the building, but little influence on the cooling load of the building. The better the insulation performance of building envelope, the greater the energy saving potential of fresh air load. Fresh air heat load is sensible heat load, and fresh air cooling load is mainly latent cooling load. From the theoretical point of view, the building adopts a heat recovery device with a heat recovery efficiency of 0.6, which can save 5989.91kW • h in the heating season and reduce the building heat load by 32.02%. In the air conditioning season sensible heat recovery device can save energy 131.45kW • h, reduce building cooling load by 1.56%; Total heat recovery device can save energy of 708.73kW • h and reduce cooling load of building by 8.43%.With the development of zero-energy building technology, the requirement of fresh air energy consumption is more strict, and the active all-heat fresh air heat recovery device is more suitable for this building. It also has more space for future development. This paper analyzes the change of energy saving potential of fresh air with the development of building envelope. The methods and ideas of reducing energy consumption of fresh air in low energy consumption buildings are discussed.