The Research of the Shading by Buildings Aside and the Efficiency of Energy Saving

• Main Authors: Hung,Te-Hsiung, 洪得雄
• Other Authors: Chang,Hsiao-Tung
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/48441182126489249136

碩士 === 中國文化大學 === 建築及都市計畫研究所 === 94 === Abstract As the use of the Earth’s resources gains increasing attention from countries around the world, architectural energy-saving issues are being researched by organizations both foreign and domestic. While Green Architecture is being promoted in Taiwan, the ENVLOAD index is being utilized to determine the energy consumption through a building’s outer casing. Since in solation (IHK) is much more important than temperature difference (DH) in the ENVLOAD formula, the influence of the shading variable (M) of a building’s outer casing on ENVLOAD is apparently far more than the heat-insulation variable (L). This is the why the outer-casing shading factor is much more important than the heat-insulation factor. Most former research into the energy-saving properties of buildings has been based on the viewpoint of a single building. Nevertheless, the relationship between buildings and their exterior environments is very closely related in the high-density land use conditions in today’s cities. Factors such as lighting, shading, ventilation etc. will be affected by nearby buildings. Nevertheless, the shading influence from nearby buildings has been ignored in The Technology Standards for Energy-Saving Design for Office Buildings. Therefore the results of building energy consumption research are not objective enough. This research is based on building-group thought and the ENVLOAD formula to analyze and revise the exterior shading variable (Ki) for an office building group. Most examples are cited from an office building group in the Taipei area. Among simulated shading influence factors (direction, height, distance), the conditions of the assumed model will be determined through related documents. The contents of each chapter in this research are briefly introduced as follows: Chapter 1 explains the motive, purpose, content, method, procedure of this research. Chapter 2 mainly introduces 0and arranges the current research results of each related field, and analyzes related laws and regulations regarding building energy savings. Chapter 3 obtains the distribution of in solation by ECOTECT computer-simulating operation to realize the influence of a building group on a heat environment, then proceeds to acquire the yearly shading percentage and radiation amount for the building outer casing through analysis of the orbital map of the Sun. Chapter 4 finally demonstrates two real-world cases to analyze and probe the influence of nearby buildings’ shade on the yearly air-conditioning electric consumption density (EUI). Chapter 5 expects to utilize a visible schematic result to bring nearby buildings’ shading effect into the shading coefficient (Ki) to consider the viewpoint of the building group in order to offer an important reference basis for further control or to revise the ENVLOAD value in the future. This research inquires into the architectural energy-efficiency of “nearby building’s shading” and finally determines the results as follows: 1. The amount of building group makes the heat environment of whole site environmental field changed and then affects the variation of building’s outer casing energy-consumption. 2. Through simulation, this research determines that the exterior shading coefficient (Ki) influenced by nearby building’s shading effect is mainly less than the basic value (Ki≦0.5) stipulated by The Design Reference Manual for Shading Energy-Saving Improvement for Old Buildings’ Outer Casing. 3. In simulating operation of actual cases, air-conditioning electric consumption density (EUI) varies due to the effect of nearby building’s shading, regardless of the south-north orientation as in Case A or the east-west orientation as in Case B. Therefore, the influence of the shading effect from nearby buildings must not be ignored when computing related architectural energy-savings in future. Keywords: ENVLOAD、 Ki、Nearby building’s shading、 Computer simulation.