Investigating the energy saving potential of applying shading panels on opaque façades: A case study for residential buildings in Hong Kong

• Published in: Energy and buildings 2019-06, Vol.193, p.78-91
• Main Authors: Liu, Sheng, Kwok, Yu Ting, Lau, Kevin Ka-Lun, Chan, Pak Wai, Ng, Edward
• Format: Article
• Language: English
• Subjects: Building design optimization; Building energy simulation; Buildings; Case studies; Configurations; Energy; Energy conservation; Energy saving; Feasibility studies; Housing; Opaque façade shading; Panels; Public buildings; Public housing; Public rental housing; Residential areas; Residential buildings; Residential density; Shading; Shading devices; Urban areas; Urban environments
• ISSN: 0378-7788; 1872-6178
• DOI: 10.1016/j.enbuild.2019.03.044

•Investigation of shading opaque façades for energy saving of residential buildings.•The impacts of climate change on cooling load are evaluated in this simulation.•Optimal shading panel configurations with the smallest areas are recommended.•Energy saving can be up to 8.0% for typical flats with the optimal configuration.•Energy saving coefficients for three parameters of shading panels are provided. In face of the warming climate, proper building designs are necessary to combat the ever-increasing energy demands, especially in high-density built environments. Shading is a common practice in subtropical cities owing to its effectiveness and feasibility. However, window shading alone is insufficient for achieving a satisfying energy performance and may often be a compromise to the visual comfort of occupants. In contrast, shading opaque façades has a great potential for energy saving with more design flexibility. This study proposes the adoption of shading devices on opaque façades and evaluates their energy saving potentials under near-extreme summer conditions by conducting building energy simulations. The length, the number, and the angle of tilt of shading panels are varied to explore the effects of different shading panel configurations for typical public rental housing buildings in Hong Kong. Optimal configurations that give maximum energy savings with the smallest total area of shading panels are found for different angles of tilt. Results show an energy saving potential up to 8.0% when shading panels are applied to flats with westward-facing façades. The energy saving coefficients within the optimal zones are also provided to guide the design of façade shading features in different urban contexts.