An actual-performance-oriented study on the relationship between environmental efficiency and passive design factors for multi-family dwellings in cold areas

Abstract

Performance during operation reflects the actual energy efficiency of the building. Therefore, when analyzing the relationship between passive design factors and building performance, using performance data in operation also makes the conclusion more in line with reality. In this study, winter and summer air temperature measurements were conducted in several multi-family dwellings in four cities in cold areas, and data on heating and cooling energy consumption of the dwellings were gathered as well. An environmental efficiency assessment method was devised to comprehensively describe residential energy consumption and environmental quality. The ratio of energy consumption to indoor-outdoor temperature difference (EDR) has been proposed as a new metric to measure the environmental efficiency of dwelling units. Through sensitivity analysis, the impacts of passive design factors on environmental efficiency were quantified and ranked. The two passive design factors that have the greatest impact on environmental efficiency in winter are northern window-to-wall ratio and surface area-to-volume ratio, while the floor number affects the environmental efficiency most significantly in summer. According to comprehensive analyses of winter and summer, the most important factors impacting environmental efficiency in a year are northern window-to-wall ratio and surface area-to-volume ratio. The study's findings can help architects filter design elements for focused design during the passive design process, increasing design effectiveness.