Environmental impacts of self-replicating three-dimensional printers

Self-replicating three-dimensional printers allow the manufacturing of parts necessary for the fabrication of cloned machines. This paradigm is particularly attractive to desktop printers, as it fosters the distributed manufacturing principle. This study assesses the endpoint environmental impacts of a self-replicating desktop three-dimensional printer through a cradle-to-gate life cycle assessment. The impacts of self-replication are measured over generations under two different initial hypotheses. The results demonstrate that human health and environmental indicators, which are mainly driven by the machine and energy, can be mitigated by reducing the building time and extending the machine lifespan. On the other hand, material consumption governs the resource depletion of the process. The analysis of the equipment shows that the replicable components only account for a small percentage of the machine materials. Accordingly, different initial hypotheses on their manufacturing determine minor changes in the total environmental impact of the process. Self-replicated machines are less sustainable than original ones with regards to human health and ecosystem quality indicators due to the long duration of the printing process. On the other hand, the design freedom of the three-dimensional printing allows for a reduction of the part weight which brings benefits to resource depletion. In the examined machine, these variations are marginal due to the small number of replicable components. Over the iterations, the environmental indicators of the self-replicated machines tend to the same values regardless of the initial hypotheses. This fact allows for the estimation of the impacts of replicated machines even if accurate information on initial manufacturing processes is unknown.