本研究於亞熱帶綠能建築技術研發測試平台SPINLab進行全尺度的實驗，利用兩相同規格的實驗空間，探討隔熱膜及電致變色膜在不同建築方位對於室內環境、室內舒適度及空調耗電的影響，在室內熱舒適度與室內視覺舒適度的分析中，額外加入吸熱膜、反射膜及Low-E玻璃共同分析比較。
從室內環境的數據我們可以發現，夏季陽光於面東上午約11:00前及面西下午約14:00後直射室內，將造成室內溫度提高，並且使玻璃溫度與玻璃熱通量提高。當清玻璃內表面貼覆隔熱膜及電致變色膜會使室內溫度降低，但因為其隔熱機制，也會導致玻璃溫度及玻璃熱通量提高。當建築面南與面北，由於不會有陽光直射室內，這些現象相對於面東與面西較不明顯。空調耗電的研究結果顯示，在清玻璃內表面貼覆隔熱膜及電致變色膜，相較於僅使用清玻璃，能有效減少空調耗電，且面西的節電效果優於面東。其中，電致變色膜霧態的效果最為顯著，其次為電致變色膜透明態，最後是隔熱膜。
熱舒適度的研究結果顯示，在清玻璃內表面貼覆隔熱膜及電致變色膜，相較於僅使用清玻璃，能有效提升室內熱舒適度，其中電致變色膜霧態與透明態的效果相似，且均優於隔熱膜。吸熱膜、反射膜及Low-E玻璃也都展現了良好的室內舒適度提升效果，其中Low-E玻璃的效果優於吸熱膜及反射膜。
視覺舒適度研究結果顯示，電致變色膜霧態及透明態雖然分別有14.2%, 31.4%的數據能降低20%以上的眩光值，但當陽光直射室內時，由於液晶液滴的光散射特性，造成電致變色膜霧態及透明態分別有26.5%, 41.5%的數據加劇了眩光影響。相對之下，使用反射膜, Low-E玻璃開窗率40% 和Low-E玻璃開窗率100% 分別只有4.2%, 7.3%, 1.9%的數據會增加眩光影響，並且分別有6.6%, 27.9%, 61.4%的數據有20%以上的眩光減少效果，眩光減少效果較為穩定，其中Low-E玻璃的效果有最好的視覺舒適度表現。

This study was conducted at the Subtropical Performance-Testbed for Innovative eNergy Research in Buildings Laboratory (SPINLab). Full-scale experiments were performed using two experimental spaces of identical specifications to investigate the effects of heat-insulation film and electrochromic film on indoor environment, thermal comfort, and air conditioning electricity consumption in buildings with different orientations. The analysis of indoor thermal and visual comfort included the additional comparison of heat-absorbing film, reflective film, and Low-E glass.
From the indoor environment data, we can observe that during the summer, when the building’s façade faces East, sunlight enters the room before approximately 11:00 in the morning, and when the building’s façade faces West, sunlight enters the room after approximately 14:00 in the afternoon, leading to increased indoor temperature, glass temperature, and glass heat flux. Applying heat-insulation film and electrochromic film to the interior surface of clear glass can lower the indoor temperature; however, due to their heat-insulation mechanisms, they also increase the glass temperature and glass heat flux. This phenomenon is much less pronounced when the building’s façade faces North or South, as there is no direct sunlight. The results on air conditioning electricity consumption indicate that applying heat-insulation film and electrochromic film to the interior surface of clear glass, compared to using clear glass alone, can effectively reduce air conditioning electricity consumption, with the electricity -saving effects being more pronounced for building’s façade faces West than building’s façade faces East. Among the different types of film, the opaque state of electrochromic film showed the most significant effect, followed by the transparent state, and then the heat-insulation film.
The research results on thermal comfort indicate that applying heat-insulation film and electrochromic film to the interior surface of clear glass significantly improved indoor thermal comfort compared to using clear glass alone. The effects of the opaque and transparent states of electrochromic film were similar and both outperformed heat-insulation film. Heat-absorbing film, reflective film, and Low-E glass also demonstrated good improvements in indoor comfort, with Low-E glass being more effective than heat-absorbing and reflective film.
The visual comfort analysis results indicate that the opaque and transparent states of electrochromic film could reduce DGP values by more than 20% in 14.2% and 31.4% of the data, respectively. However, due to the light scattering properties of the liquid crystal droplets, the opaque and transparent states of electrochromic film increased DGP values in 26.5% and 41.5% of the data, respectively, when sunlight directly entered the interior. In contrast, the use of reflective film, Low-E glass with a 40% window-to-wall ratio, and Low-E glass with a 100% window-to-wall ratio only increased DGP values in 4.2%, 7.3%, and 1.9% of the data, respectively, and reduced DGP values by more than 20% in 6.6%, 27.9%, and 61.4% of the data, respectively. The DGP reduction effect was more stable, with Low-E glass providing the best performance in terms of visual comfort.

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