優化被動式策略對於可持續城市規劃和建築設計 為了降低都市熱島並增加建築能源效率

Abstract

缺乏精心設計建築物的都市模式增加城市熱量和能源需求。太陽能控制技術的策略,如果正確地設計和應用,可降低太陽輻射及冷卻需求。本研究旨在設立並推薦兼具最有效性及平衡性，可減緩城市熱島效應並提升建築物能源效率的被動解決方案。精心設計的建築物將有助於降低的室外溫度、日照時數、太陽輻射強度與室內冷卻之需求，而增加陰影範圍和節能。本研究回顧了三類主要的微氣候控制類別:都市景觀佈局，街道峽谷佈局與天空视域因子。進行了一個基準案例及七個有懸垂裝置系統的模擬。檢查了四類主要的太陽能控制類別:自己的陰影門面、日光遮陽裝置，窗戶到牆面比例與建築方向。微氣候控制的結果顯示，都市景觀布局下的遮蓋草地案例可有效的將地表及空氣溫低分別降低達52.51％及50％。日光遮陽裝置模案裂果顯示傳統懸垂裝置系統可將都市日照時數降低66%。另一方面，多重懸垂裝置系統的組合在對於阻擋尖峰時段的總太陽輻射最為有效，可降低建築室外太陽輻射強度達76.8％，並增加21.5%的陰影範圍，導致節能潛力高達8.92％。在被動式案例的太陽能控制中，從太陽輻射強度、日照及能見度的最有效及平衡解決方案的角度是複雜設計的自己的陰影門面和日光遮陽裝置，節能潛力可達66%。被動式策略的戰略放置和準確設計可以進一步提升戶外及室內的成效。對建立最適建築門面為了戰略放置的複雜及簡單設計與形狀而言，最佳建築方向是關鍵。計算了出59個位置的方位角度提供全球範圍的指南。結果顯示若要達到防止太陽輻射，58.62％的地點應於其東方設置複雜設計，24.13％於其東北方，12.06％於其西方及5.17％於其東南方。在熱帶及亞熱帶地區，複雜設計可與再生能源技術相結合。

Urban patterns without highly designed buildings increase urban heat and energy demands. Solar control techniques encompass strategies that – if properly designed and applied – can decrease solar radiation and cooling demands. This research aims to establish and recommend the most effective and balanced passive solutions to mitigate the effects of the urban heat island and enhance buildings’ energy efficiency. A highly designed building will contribute to a decrease in outdoor temperatures, as well as sunlight hours, insolation and indoor cooling demands, which could increase the shading range and the energy savings. Three main classes of microclimate control are reviewed – urban landscape layout, street canyon layout and sky view factor. A base case scenario and seven with overhang device systems are simulated. Four main classes of solar control are examined – façade self-shading, shading devices, window-to-wall-ratio and building orientation. The results show that within the microclimate control, the shaded grass case under urban landscape layout class effectively lowers surface and air temperatures by as much as 52.51% and 50%, respectively. The case under shading device class demonstrates that a traditional overhang device decreases the urban site’s sunlight hours by up to 66%. On the other hand, the combined overhang device systems have the highest capacity for blocking total solar radiation during peak hours, thus decreasing the insolation ratings in the buildings’ outdoor by up to 76.8% and gaining shading on the envelope of up to 21.5%, resulting in potential energy savings of up to 8.92%. Within solar control, the passive cases show that the most effective and balanced solutions in terms of insolation, daylighting and visibility are complex designs of façade self-shadings and shading devices, which achieve potential energy savings of up to 66%. The strategic placement and accurate design of passive strategies can further improve the outdoor and indoor performance. Optimal building orientation is essential for determining most favourable façades for the strategic placement of both complex and simple designs, as well as building shapes. Azimuth angles are calculated for 59 locations to provide a worldwide guide. The findings indicate that 58.62% of the locations should apply complex designs to the east, 24.13% to the northeast, 12.06% to the west and 5.17% to the southeast orientations for solar protection. In tropical and subtropical zones, complex designs can be integrated with renewable technologies.