This paper discusses the role of geometry parameters including building shape, window to wall ratio, room depth, and orientation on the energy use and thermal comfort of school buildings in cold climates of China. The annual total energy demand and summer thermal discomfort time were compared through computer simulations with DesignBuilder. Furthermore, a questionnaire was conducted that related to the students’ subjective preference for various building geometry parameters. Results showed that a maximum of 13.6% of energy savings and 3.8% of thermal comfort improvement when compared to the reference case could be achieved through variations in geometry parameters. The H shape performed the best when the building thermal performance and students’ preferences were considered, as well as the various design options for architects. Window to wall ratio, room depth, and orientation should also be carefully addressed in terms of different building types. The results of this study can serve as a reference for architects and school managers in the early design stages of schools in cold climates of China.
The existing building stock has been in the focus of European Union policies for energy savings. Nevertheless, energy certification schemes refer mostly to operational energy and usually do not consider aspects related to the life cycle of the building. To look at the overall energy cost during the lifespan of a building, the energy used to produce and assemble the building materials also needs to be included. This paper develops a design methodology for existing residential buildings that aims at decreasing the life cycle energy use as much as possible. This approach was applied on a case study of an existing post-war residential building in Utrecht, The Netherlands. The main focus of this study is to find a design solution for façade retrofitting that considers both embodied and operational energy. The design approach is based on comparing different strategies for the use of façade materials. This design methodology can be replicated in other projects, as the conclusions and recommendations can also be used for future refurbishment projects for which a low operational energy and materials with a low embodied energy are desired.
18 November 2019 in Smart and Sustainable Built Environment
Purpose: Refurbishing houses is considered a key measure to improve the energy efficiency of the built environment. However, little is known about the implementation and outcome of housing renovation for energy upgrades in the Vietnamese practice. The purpose of this paper is to investigate the energy performance of the current housing stock in Vietnam and the potential to reduce energy use in households.Design/methodology/approach: The paper is based on a survey with 153 respondents in three major climatic regions of Vietnam. The survey focusses on building characteristics, environmental performance, energy performance and refurbishment activities. Data collected from the survey were statistically analysed to give insight into the current performance of the housing stock and its energy saving potential.Findings: This paper concludes that building design and construction, particularly the building envelope, have a significant influence on the occupants’ comfort. However, the energy consumption in houses is not statistically associated with building design and indoor environment. It is suggested that financial status and occupants’ behaviour currently have a strong influence on the household energy use. The survey also showed that refurbishment improves the housing performance, especially if improving the indoor environment was one of the drivers.Originality/value: There are very few studies on energy use in households in Vietnam, especially with regards to actual energy consumption. This paper brings insights into the actual energy consumption and reveals the “performance gap” in Vietnamese housing stock.