行為干預對辦公室能耗之影響–窗簾使用行為改變之實例探討

Abstract

台灣的辦公大樓平均耗電比例，空調用電約佔48%，因此要降低辦公大樓的能源消耗，空調用電是最關鍵的部分。除了特殊的綠建築設計，使用效率較高的空調系統也是有效節省空調用電的方法。不過對於既有的建築而言，重新設計建築或是更換空調系統的成本過高，因此發展技術干預方法改變現有設備的操作或是行為干預方法改變人的行為模式是更適合的節能方法。 為了發展適用於辦公大樓的節能手段，本研究以台北市政府辦公大樓作為研究場域，在與台北市政府公管中心進行多次的會議討論後，決定以行為干預作為節能的方案，並將目標設定為「增加隔熱窗簾使用率」，並且與國立台灣大學智慧生活科技整合與創新研究中心合作發展出四種干預手法：設定預設值、節能小卡與承諾磁鐵、張貼提醒標語、全棟廣播，並以適當的方法評估節能效益。 本研究首先以「窗簾遮蔽率改變」來分析窗簾遮蔽率是否有顯著改善，然後再以「空調耗能基線法」預測台北市政府的空調冷卻負荷及用電量，於執行干預後再與實際的能源消耗作比較，評估節能效益。而「外牆熱傳公式法」及「外牆熱傳模擬法」則是分別計算干預前及干預後經由熱傳導及太陽熱輻射從外牆進入室內的熱量，比較兩者後再評估節能效益。而室內的熱舒適也是大家非常關心的議題，本研究也透過物理模擬軟體的分析，將不同窗簾遮蔽率下的室內溫度視覺化，讓拉窗簾的效果更能清楚呈現。 以上四種方法皆能看出窗簾行為干預的效益，可以視干預手法的種類及實施場域的狀況選擇適合的評估方法。從行為的角度來看，以設定預設值的效果最佳，而全棟廣播則是最容易實施的干預手法。本研究的結果己納入國立台灣大學智慧生活科技整合與創新研究中心編製的「數據與行為節能參考指引」，同時將參考指引置於本書附錄，讀者除了可以查閱詳細的行為干預設計方法，指引中也有更多種適用於辦公大樓的技術、行為干預手法可以參考。

The ratio of the power consumption of air conditioning is about 48% on average among all office buildings in Taiwan. Therefore, reducing air-conditioning power consumption is an important issue. Green building design or high-efficiency air conditioning is effective in energy saving. However, changing building design or using a high-efficiency air conditioning system is costly, maybe even impractical for existing buildings. Behavioral intervention requires no building renovation or facility replacement. Hence, it is a near-zero cost solution for energy saving. The purpose of this research is to study the effectiveness of behavioral intervention in the energy saving of office buildings. Four behavioral interventions were implemented in the Taipei City Hall. The target was to improve the usage of curtains. The interventions were: setting default, energy-saving cards, reminder posts, and broadcasting. Three indices were developed to measure the effectiveness of each intervention, namely, the increase of curtain shield ratio, the decrease of cooling load, and the decrease of heat transfer through the external wall and windows. Two ways were adopted to determine the heat transfer: empirical formulas and simulations. The influence of the curtain shield ratio on the indoor temperature distribution and thermal comfort was also investigated by simulation. These four methods can all be used to measure the effectiveness of each intervention, and the choice depends on what intervention we use and where we use the interventions. Among all the interventions, setting default is the best intervention, and broadcasting is the most user-friendly intervention. The result of this study was incorporated into the Data and Behavior-Based Energy Saving Handbook published by NTU INSIGHT in 2018.