Green inventory model with two-warehouse system considering variable holding cost, time dependent demand, carbon emissions and energy consumption

One of the key components of inventory modelling is the consideration of energy consumption while storing inventory, which can increase holding cost and releases carbon emissions. In business practices, suppliers give their retailers discounts on large orders, typically during the festival seasons, to attract customers, boost sales and earn more profit. For this, they may require warehouses, which need to keep at favourable environmental conditions according to products. Demand can be constant, linear, fluctuating, or extremely high with regard to time. Therefore, time-dependent quadratic demand has been incorporated in this study. Here, energy and carbon emission costs have been introduced so that the average inventory cost per unit time is the minimum and optimum values for the decision variables are determined. Energy and carbon emission costs are evolved in holding costs during product stocking. The proposed model is validated with a numerical example, and managerial insight has been provided based on the sensitivity analysis.