全球暖化現象日益嚴重，已直接地影響我們的生活，凸顯減少碳排放、控制地球平均溫度的重要性。航空產業作為重大排放源之一，實施更積極的減碳措施已是刻不容緩。對此，國際民航組織擬定提升航空科技、提高營運操作效率、使用永續航空燃油等，搭配實施碳市場機制措施，以期達成航空部門淨零排放的目標。
除了航空產業內之減碳對策，旅客也能自願參與航空公司的碳抵換計畫，以購買之減量額度，抵銷自身航空旅行碳足跡，共同減少航空旅行對環境產生的影響。但自願碳抵換計畫實施以來，推行成效非常有限。因此，本研究調查旅客參與航空自願碳抵換計畫之動機與阻礙，並以選擇實驗探討足以促進旅客參與計畫之誘因，以及旅客對抵銷碳排放的願付價格，找出支持碳抵換之潛在旅客群集。
研究結果顯示，多數受訪者對於永續、低碳知識與責任已具有相當之意識，但多數不了解航空自願碳抵換計畫，使得參與率低下。透過分群，可將受訪者分為性價比導向、高度環保導向、保守導向等三群。性價比導向群佔比超過一半，若能搭配其他誘因或優惠，將提高此群購買碳抵換的可能性；高度環保導向群佔比將近4成，期望抵銷更多碳排放量，且重視航空公司永續策略，願意以較高金錢支持碳抵換計畫；保守導向群佔比不到1成，為不願意購買碳抵換之群集。願付價格結果顯示，在情境背景下，受訪者整體平均願意付出約670至830元抵銷個人碳排放，此估計結果高於過去相關研究之結果。另外受訪者對於額外哩程數或額外免費行李重量具有較高偏好，願付價格皆達到約400元，可作為未來強化參與碳抵換之可能誘因。綠色永續標章之願付價格約為370元，也顯示出受訪者對航空公司永續策略之重視。未來建議航空公司持續推廣自願碳抵換計畫，提高民眾認知，並簡化購買流程，降低阻礙，同時考慮搭配適當優惠或誘因，提高意願。針對主管機關，建議可將自願碳抵換推廣成果，納入航空公司評鑑指標中，提高對自願碳抵換之重視度。

Global warming is increasingly impacting our lives, emphasizing the urgent need to reduce carbon emissions and control Earth's average temperature. As a major emission source, the aviation industry must implement more aggressive carbon reduction measures. The International Civil Aviation Organization has proposed strategies including improved aviation technology, enhanced operational efficiency, and sustainable aviation fuels, complemented by carbon market mechanisms, aiming to achieve net-zero emissions in the aviation sector.
Besides industry measures, passengers can voluntarily participate in airlines' carbon offset programs, purchasing emission reduction credits to mitigate their travel's carbon footprint. However, these voluntary programs have shown limited effectiveness since implementation. This study investigates passengers' motivations and barriers to joining aviation voluntary carbon offset programs, using choice experiments to explore incentives for participation and willingness to pay for offsetting emissions, aiming to identify potential supportive passenger segments.
Results show that while most respondents are aware of sustainability issues and low-carbon responsibilities, many lack knowledge about aviation voluntary carbon offset programs, leading to low participation rates. Through clustering analysis, respondents were divided into three groups: value-oriented, highly environmentally oriented, and conservative. The value-oriented group, comprising over half of the respondents, is more likely to purchase carbon offsets if combined with other incentives or benefits. The highly environmentally oriented group, accounting for nearly 40%, desires to offset more emissions and values airlines' sustainability strategies, willing to support offset programs at higher costs. The conservative group, less than 10%, is unwilling to purchase carbon offsets. Willingness-to-pay results indicate that respondents are on average willing to pay about NT$670 to NT$830 to offset their individual carbon emissions, higher than previous studies. Respondents show high preference for extra mileage or free baggage allowance, with willingness to pay reaching about NT$400. The willingness to pay for green sustainability labels, at about NT$370, also indicates respondents' emphasis on airlines' sustainability strategies. Recommendations include airlines promoting voluntary carbon offset programs, raising awareness, simplifying purchase processes, and considering appropriate incentives to increase participation. For authorities, it is suggested to incorporate the promotion results of voluntary carbon offsetting into airline evaluation indicators.

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