碳排放量資訊之價值攸關研究──以台灣高碳排產業公司為例

本文以2016年至2021年台灣之高碳排產業（石化、電子、鋼鐵、水泥、紡織、造紙業）公司為研究對象，利用Ohlson (1995)之評價模型探討其總碳排放量資訊及區分範疇下（範疇一與範疇二）之碳排放量對公司價值之影響。另外，亦檢測碳排放量揭露政策（有揭露或未揭露碳排資訊）是否對碳排放量資訊之價值攸關性存在差異，而對於未揭露碳排放公司，本文參考Griffin et al. (2017)以碳排放量估計模型估計其碳排放量。本文實證結果顯示在高碳排產業中，投資人對總碳排放量、範疇一或範疇二之碳排放量資訊，皆給予負向評價；相較於未揭露碳排量之公司，投資人對有揭露碳排放量之公司之總碳排放量給予較小之負向評價，即公司碳排放量資訊揭露之政策能減緩投資人對總碳排量之負向評價。

This study focuses on Taiwan’s high carbon emission industries (petrochemical, electronics, steel, cement, textiles, and paper industries) from 2016 to 2021, applies Ohlson’s (1995) valuation model to examine the impact of the total carbon emissions and the carbon emissions in different scopes (Scope 1 and Scope 2) on firm value. Additionally, this paper also examines whether the value-relevance of Carbon Emission differs under different disclosure policy of carbon emission information. This paper adopts the carbon emission estimation model proposed by Griffin et al. (2017) to estimate the carbon emissions of companies that did not disclose information of carbon emission during the sample period. The empirical results show that in high carbon emission industries, investors give negative evaluations to companies with the total carbon emissions, the Scope 1 emissions, and the Scope 2 emissions. Moreover, companies that disclosed their carbon emissions receive relatively less negative evaluations on their total emissions compared to companies that did not disclose such information. This suggests that the policy of disclosing carbon emission information can mitigate investors’negative evaluations of total carbon emissions.