Emergy-based method for the sustainability assessment and improvement of additive manufacturing systems

Additive manufacturing (AM) can be used to fabricate products with complex shapes that cannot be realized with traditional manufacturing. However, when manufacturing large metal components, AM is constrained by extended production cycles and reduced efficiency, leading to substantial resource usage and environmental impacts. To clarify the environmental impact and sustainability (EIS) of AM systems and improve their resource utilization and economic benefits, an emergy-based approach was proposed. Initially, the scope and boundary of the approach are defined, and the methodology and preparatory steps are detailed. Subsequently, emergy models for sustainability evaluation are established, including factors such as production time, quality, resource use, costs, and economic performance. A comprehensive evaluation is conducted to determine the relevant indices. The results of the evaluation of three distinct AM processes reveal that resource and energy utilization in AM systems contribute approximately 50% of the environmental impact. To mitigate the environmental impact of AM systems and improve their sustainability, reducing the energy consumption of AM systems is indicated as an effective strategy. Our method quantitatively evaluates the EIS of AM, providing a basis for informed decisionmaking to reduce environmental impact while enhancing production efficiency and economic benefits.