A sustainable inventory model for a two-echelon cold chain with green technology investments and stock-dependent demand under carbon emissions tax regulation

Abstract

Cold chains are specialised supply chains that make use of refrigerated storage facilities and distribution nodes. Products that have to be stored and distributed via cold chains are temperature-sensitive items such as perishable food or vaccines. If these products are not maintained at the correct temperatures, their safety and quality may be comprised with dire consequences for end-users. Operating refrigerated storage units consumes a lot of energy and the majority of transportation trucks used for distribution are powered by fossil fuels and therefore, cold chains are a major source of carbon emissions. With this in mind, this paper proposes a sustainable inventory model for a two-echelon cold chain with stock-dependent demand and green technology investments under a carbon emissions tax regulation. The carbon tax is imposed by policy makers to encourage the cold chain to reduce its emissions whereas, the green technology investment is a voluntary measure taken by the cold chain to reduce its carbon emissions. Based on the results, a carbon tax regulation is about 3% more effective than a green technology investment in terms of profit maximisation potential. Moreover, when it comes to investing in green technologies, there is an optimal investment amount above which increasing the investment results in decreased profits and increased emissions. Other avenues that the cold chain can explore in effort to improve profitability include increasing the potential market size, displaying higher volumes of stocks, using larger capacity transportation trucks and filling the trucks to capacity.