碳排放交易機制中超額排放與碳價變動 對企業營運績效之影響分析 ──以歐洲航空業實證為例──

Abstract

隨著全球碳中和目標推進，歐洲碳排放交易制度（EU ETS）對企業營運成本的影響日益受到關注。航空業作為碳密集產業，在被納入 EU ETS 規範後，面臨逐步減少免費配額、並須自負碳排成本的挑戰。在碳價持續上升、碳市場波動性加劇的背景下，企業如何管理超額碳排放風險，成為評估其財務表現的重要議題。特別是在 COVID-19 疫情造成航空運量劇烈波動的情況下，更需釐清碳排放行為與營業績效之間的關聯性。 本研究聚焦於 2012 至 2024 年歐洲九家航空公司，以固定效果面板回歸模型實證檢驗超額碳排放量、碳期貨價格、碳價波動度及 COVID-19 疫情對企業營業利益的影響。模型中納入公司與年份固定效果，並採用公司層級叢聚式穩健標準誤（Clustered Robust SE）與 Winsorization 極端值處理以提升推論穩定性。進一步透過交互作用項檢驗碳價變動是否放大超排成本的財務衝擊，並觀察疫情期間是否對該關係產生干擾效果。 研究結果顯示，超額碳排放量與營業利益呈現正向顯著關係，顯示在現行碳價水平與免費配額尚未完全取消的制度下，碳排放成本對營運尚未構成明顯壓力。碳期貨價格對營業利益呈接近顯著的負向影響，顯示未來若碳價進一步上升，航空公司可能面臨更嚴峻的利潤壓縮。碳價年化波動度則呈正向且接近顯著影響，可能反映部分企業具備風險管理與市場調整能力，能在波動中尋求對策。交互項與疫情變數雖未達統計顯著水準，然整體模型解釋力良好，且主要變數在各模型下結果一致，支持研究推論之穩健性。

As global efforts toward carbon neutrality intensify, the European Union Emissions Trading System (EU ETS) has become an increasingly important factor influencing corporate operating costs. The aviation industry, as a carbon-intensive sector, faces mounting cost pressures due to declining free allowances and the need to purchase additional carbon permits. In the context of rising carbon prices and increasing market volatility, understanding how companies manage the financial risks associated with excess emissions is essential. This is especially relevant given the operational disruptions caused by the COVID-19 pandemic, which further complicate the relationship between emissions behavior and financial performance. This study examines panel data from nine European airlines between 2012 and 2024, employing a fixed effects panel regression model to empirically investigate the impact of excess carbon emissions, carbon futures prices, carbon price volatility, and the COVID-19 pandemic on firms' operating profits. The model incorporates firm and year fixed effects and applies clustered robust standard errors at the firm level as well as Winsorization to mitigate the influence of extreme values. Interaction terms are used to test whether carbon price movements amplify the financial burden of excess emissions and whether the pandemic interferes with this relationship. The results show a significant positive relationship between excess emissions and operating profits, suggesting that under the current pricing levels and with free allowances still in place, carbon costs have not yet imposed substantial financial pressure. Carbon futures prices exhibit a marginally significant negative effect, indicating that future increases in carbon prices may compress profit margins. Carbon price volatility shows a marginally significant positive effect, possibly reflecting firms’ ability to manage risks and adapt to changing market conditions. While the interaction term and COVID-19 variable are not statistically significant, the models exhibit good explanatory power, and the core variables remain consistent across different model specifications, supporting the robustness of the findings.