含減碳投資之隨機需求整合存貨模式

全球暖化及溫室氣體的排放已成為現今不容忽視的環境議題，因而許多關於生產存貨問題的研究開始加入碳排放規範的討論，或進一步考慮投資綠能科技來減少碳排放量，藉此制定較佳的決策或作業方式，期達到永續經營的目標並負起社會環境責任。本文在隨機需求的環境下，針對兩種碳排放規範(碳稅，及限額與交易)並考慮減碳投資方案，據此建立買賣整合存貨模式，目標為制定最佳的減碳投資與存貨策略，決策變數包括訂購數量、再訂購點、運送次數、及減碳投資金額，以達到系統期望總成本最小化。有關前置時間內需求量之分配，則考慮傳統的常態分配及分配形式未知兩種情形。本研究透過數值範例來說明模式的求解結果，同時進行敏感度分析；數值結果顯示，含減碳投資之碳稅規範模式與傳統模式相比，總碳排放量減少；含減碳投資之限額與交易規範模式與傳統模式相比，系統期望總成本及總碳排放量均減少。

關鍵字

減碳投資；碳稅；限額與交易；隨機需求；整合存貨模式

並列摘要

Global warming and greenhouse gas emission have become an environmental issue now, so many studies related to the production and inventory problems begin to discuss carbon emission policies, or further consider through investing green technology to reduce carbon emission. The idea is by making better decisions or operating methods to achieve the objective of social environmental sustainability. This study establishes a vender-buyer integrated inventory model under stochastic demand with regard to two carbon emission policies (tax and cap-and-trade) and emission reduction investment plan. The objective is to find the optimal investing and inventory strategy for the model, which decision variables are order quantity, reorder point, number of shipments, and amount of emission reduction investment, so as to minimize the expected total cost. Besides, for the lead-time demand, we consider the normal distribution case and distribution free case. We use numerical example to illustrate the results of proposed models and perform sensitivity analysis. The numerical results show that comparing the tax policy model with emission reduction investment to the traditional model, the total carbon emission is reduced. Comparing the cap-and-trade policy model with emission reduction investment to the traditional model, both the expected total cost and total carbon emission are reduced.