Renewable-Energy-Based Global Supply Chain Network Design for Greenhouse Gas Reduction: A Comparison of Different Assembly Products

Greenhouse gas (GHG) emissions in global supply chains can be reduced by introducing renewable energy (RE) systems such as solar power generation systems. Some manufacturers commit themselves to the RE100 global initiative that encourages companies to source 100% of the electricity used in their business operations from RE. Thus, suppliers will face the risks of contract termination if suppliers fail to satisfy the target RE utilization rate to reduce GHG emissions. Besides costs, GHG emissions from electricity consumption during component production and GHG emissions from material production differ among suppliers due to differences in the availability of RE and regional energy mixes. Hence, in this study, we proposed a RE-based global supply chain network to reduce GHG emissions using an optimization model to satisfy the target RE utilization rate and GHG reduction rate simultaneously, where we considered the GHG emissions from electricity consumption and material production. In our model, the suppliers were allowed to purchase electricity generated by non-RE systems when they could not fulfill the electricity required to manufacture components from RE systems. We compared the RE utilization rate, GHG emissions, and total cost for two products (laptop and vacuum cleaner). We analyzed five scenarios for four countries (China, Malaysia, the United States, and Japan) where only one country implemented 100% RE, whereas the others installed 20-kW solar power generation systems and purchased additional electricity from non-RE providers. Both the laptops and vacuum cleaners exhibited a similar trend in terms of the GHG emissions and total cost.