Study On Passive Design Strategies And Energy Saving Performance For Wannan Vernacular Dwellings

The climate and technology has been the key elements affecting architecture forms and development. With the development of society, the building area grows up rapidly. How to create a comfortable indoor environment with less building energy consuming has become an important issue. After reform and opening up, rural areas develop quickly and the energy demand rises up. If rural dwellings inherit the construction methods from traditional dwellings or simply copy the methods from urban dwellings, the consequence may lead to bad environmental quality, increase of energy consuming and pollutant emission. Therefore, the only way is to study on passive design strategies depend on local climate.The passive design approaches for transformation of Huizhou residence in Wannan region are carried out by studying the bioclimatic experiences used in Wannan traditional dwellings, the problems existing in modern dwellings in Wannan and the local thermal comfort zone. Absorbing the bioclimatic experiences used in the old, modern climate adapted approaches and other outer factors organically are integrated into design methods. The study also uses a particular assessment method of energy saving performance to quantitatively analyze the effects for optimum passive design schemes.Through field studies, the problem existing in the traditional one is low indoor air temperature with high humidity in winter while it is comfort relatively in summer still with the problem of high humidity. The newly-built dwelling is improved in its indoor thermal environment, however, the indoor air temperature in winter is still low and summer indoor humidity is excessive.Local climate is the limiting condition to vernacular architecture and appropriate passive design strategies. 30 years’ weather date is used to analyze the question of high humidity in both winter and summer. Bioclimatic analysis by Givoni is adopted to work out the appropriate passive design strategies based on local climate and human thermal comfort. The passive solar design and natural ventilation are suitable for Wannnan and their effective use time ratios are calculated.The optimizations of different passive design strategies are tested by building energy simulation E+ and CFD ventilation simulation and figured out the energy saving contribution ratio of passive design is 71%.