本研究參考Alberola et al.(2008)一文設置能源價格變數、能源相關變數及極端天氣等變數，並運用時間序列GARCH模型，探討上述變數對二氧化碳的影響(本文令為原始碳價模型)，接著討論碳價設置上限機制後，再比較三種上限水準高低對碳排放交易價格的影響。以下依限價水準高低令為高、中、低限價模型。 實證結果發現，低限價模型使得歷史碳價失去其參考價值；中限價模型中，所有變數皆具顯著，其中石油、煤炭與CDS等變數對碳價具有正向影響，與預期相符；而高限價模型，則具有最不扭曲原始碳價格數列的性質，因此其估計結果與原始碳價模型最為相似。比較三種上限模型，估計結果有以下重點：1.碳價落後期隨上限水準的上升而逐具顯著性；2.傳統石化能源價格(石油與煤炭)確為碳價上升的主因。 有鑑於歷史碳價的波動現象與文獻研究結果，得知高碳價會使廠商面臨鉅額的成本支出，過低的碳價卻有礙於碳權市場的發展，甚至不利溫室氣體減量的目標。本文三種限價模型，呼應文獻的結果，過高或過低的限價水準皆不利溫室氣體減量及市場的發展。 Refers to the paper wrote by Alberola et al. (2008), this study establishes the model with energy variables, energy-related variables and extreme weather variables by GARCH model. First, this paper discusses the influence of Carbon price (set as primitive carbon price model) on those above variables. Then it set up an upper limit (cap) on carbon price series, and compares the results under three different kinds of price cap level. Two main results from the comparison above: 1. the lagged carbon prices will be more significant with higher carbon price cap; 2. the emission intensive energy sources (petroleum and coal) are the principal factors in the determination of CO2 prices. Due to those researches investigated by literature, high carbon price will bring large amount of cost for the manufacturers, but the excessively low carbon price will deter the development of carbon trading market. This article addresses three kinds of price-limited model. The results extend previous literature by showing that either excessively high or low cap level won’t contribute to greenhouse gas decrement and the market development.
