政府涉入綠色供應鏈之最適經濟政策模型

Abstract

綠色供應鏈的理念係考量產品整個生命週期之整合，由於能同時兼顧企業營運與國際環保的目標，能提升產業永續的競爭力，故受到廣泛的認同。然而，透過市場機制的運作，通常會忽略逆向供應鏈所產生的環境效益，使得綠色供應鏈無法充分的運作。故本研究亟欲探討為促進綠色供應鏈的運作能有效率，政府使用經濟誘因政策涉入的影響效果。 本研究構建一個三階段的賽局模型進行分析，試圖在同時考量政府與綠色供應鏈成員決策互動的過程，以及處於寡佔市場的綠色供應鏈間具生產競爭行為下，制訂出最適的經濟政策。根據模型，應用賽局理論進行求解，可求得政府的最適經濟誘因政策，以及均衡狀態下綠色供應鏈成員的最適營運決策，包含最終產品產量、原物料價格、再生物料價格。此外，最終產品的最適回收水準也可被計算出來供環保立法參考。 本研究之分析結果顯示，由於政府透過課稅與補貼的經濟誘因政策之社會福利水準高於不使用經濟誘因政策下的社會福利水準，經濟誘因政策的影響效果良好。經濟政策有助於鼓勵逆向供應鏈將回收產品進行回收與處理為再生物料，並且誘導供應鏈的最終產品製造商增加購買再生物料，以達到最適的回收水準，使綠色供應鏈的運作能更有效率。政府亦可根據影響費率與補貼金的相關影響變數，調整其經濟誘因政策，相關影響變數包括消費最終產品對環境產生的邊際損害成本、回收產品回收處理的環境效益、綠色供應鏈廠商數目。

The concepts of Green Supply Chain (GSC) referring to the integration of managing the overall lifecycle of products toward sustainable competitive advantage of business operations coexistent with the protection of global environments have been extensively recognized. However, the environmental benefit oriented from the reverse-supply chain can be easily ignored in a green supply chain by market mechanism. This study investigates the influential effects of the government’s use of economic incentives on GSC to enhance the operational efficient of GSC. This study constructed a three-stage game model to find out an optimal economic policy to involve the GSC of considering interaction between government and members of GSC and the competitive behavior in oligopoly chain-to-chain. Game theory is then used to seek the solutions, including the government’s economic incentives policy, the operational decisions of GSC for the quantity of output, price of raw materials and recycle materials, under equilibrium conditions. In addition, the optimal return rate of end-of-life product can also be induced for green legislation. In the results, the social welfare of using the economic incentives policy, e.g., subsidies and taxes, is higher than using no economic incentive. So the influential effects of the economic incentives policy are obvious. It urges the reverse-supply chain to recycle and reuse and induces the supply chain to buy recycle materials to achieve the optimal return rate and to accomplish the integrated goals of GSC. Government can adjust the economic incentives policy according to the environmental damage cost of consuming products, the environmental benefit of recycling and the number of the GSC.