三種碳稅制下廠商產品最佳生產與定價策略

Abstract

全球暖化所帶來之氣候異常愈趨頻繁，各國開始反思經濟行為所排放之溫室氣體污染，將對環境造成破壞。各國相繼擬定碳關稅，而臺灣尚未對國內實施完善碳管制政策，國家應思考如何規範國內碳排放政策以增加出口企業競爭力。再製造作為一延續產品生命週期之方法，許多研究顯示此方法能有效降低產品碳足跡，並提升廠商利潤與消費者社會福利。本論文針對一獨佔廠商，在無管制與三種減碳政策下，面對具綠色消費思潮之需求函數，替廠商建立最佳化生產與定價模型。研究結果發現，消費者愈實踐綠色消費主義，廠商獲利與再製品產量會提升，且可以降低整體總碳排放。在碳稅制下，獨佔廠商會轉嫁稅賦至消費者，減碳效果不明顯。在強制碳限額制度下，限額愈寬鬆或罰金金額愈低，會使廠商獲利增加但增加碳排放;碳交易制度下，碳權價格愈高，廠商獲利會增加且碳排放會減少，但碳市場價格波動幅度大。故立法者在制定政策時，應妥善思考預期減碳效果與經濟成長間之平衡，以及如何防範投機者所造成碳市場間失靈狀況。

The frequency of extreme climate events have been accelerating by global warming, many countries started to rethink the environmental damage by greenhouse gas, emitted from human economic activities. Some of them formulated “Carbon border tax” in succession, however, there isn’t any complete carbon emission policy in Taiwan. The government ought to take it into account to enhance the competitiveness of exporting business. Remanufacturing, a method to extend the life cycle of a product, has been proved an effective way to reduce the product’s carbon footprints and improve the firm’s profits as well as consumer welfare by many studies. This paper aims to build up an optimal production and pricing model under three carbon emission policies by considering a monopolist facing a demand function which include a “green consumerism factor”. The result show that, the more green consumerism is popular, the more quantities of the remanufactured product will be produced. The firm can not only earn more profits but decrease its carbon emissions as well. Under the carbon tax policy, the monopolist will pass all of the tax incidence along to its consumer, and thus make it ineffective in reducing carbon emission. Under the mandatory carbon emissions capacity policy, the firm’s profits can increased when the government tend to relax the regulation, but it will also generate more carbon emissions. Under the cap-and-trade policy, the firm can increase its profits and cut down its carbon emissions at the same time if the price of carbon credits is high. However the price in trading market is fluctuating dramatically with time. As a result, the policymakers should find a balance between the goal of carbon emission reduction and economic growth. Meanwhile, figuring out how to prevent the trading market failure, usually caused by speculators, before implementing related policies.