Innovative Energy-efficient Building Technologies:
Passive Radiative Cooler and Smart Window
Among the various energy-efficient building technologies that have been developed through an ongoing RGC CRF project under the leadership of Prof. Christopher Chao (Dean of Engineering and Chair Professor of Mechanical Engineering at HKU), passive radiative cooler and smart window are the two innovative and promising technologies, which are especially ripe for introducing to industries.
Passive radiative cooler is a wall panel for building façade to provide cooling effect for indoor environments by radiative cooling. Radiative cooling is a process of heat removal from a sky-facing surface to the universe. It is a passive way requiring no additional energy input like electricity.
Smart window responses to external stimulus such as voltage (electrochromic), heat (thermochromic) and light (photochromic). These windows regulate their characteristics in terms of optical and thermal properties. Thermochromic smart window blocks solar radiation at high temperature or allow incoming radiation in during cold weather to maintain indoor thermal comfort.
The potential of these technologies in energy saving for buildings has been proven by different thermal analysis like field experiment and energy simulation software. Installation of passive radiative cooler and thermochromic smart window can reduce solar heat gain and HVAC energy consumption and more importantly, they require no electricity and are environmental-friendly.
一個由港大工程學院院長及機械工程講座教授 - 趙汝恆教授領導的RGC CRF項目研發了各種各樣的節能建築技術。被動式無源輻射冷卻器和智能窗戶是其中兩種創新而又成熟的技術，能夠將其引入行業。