Environmental Life Cycle Analysis of Distributed Three-Dimensional Printing and Conventional Manufacturing of Polymer Products

Abstract

With the recent development of the RepRap, an open-source self-replicating rapid prototyper, low-cost threedimensional (3D) printing is now a technically viable form of distributed manufacturing of polymer-based products. However, the aggregate environmental benefits of distributed manufacturing are not clear due to scale reductions and the potential for increases in embodied energy. To quantify the environmental impact of distributed manufacturing using 3D printers, a life cycle analysis was performed on three plastic products. The embodied energy and emissions from conventional large-scale production in low-labor cost countries and shipping are compared to experimental measurements on a RepRap with and without solar photovoltaic (PV) power fabricating products with acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA). The results indicate that the cumulative energy demand of manufacturing polymer products can be reduced by 41−64% (55−74% with PV) and concomitant emission reductions using distributed manufacturing with existing low-cost open-source 3D printers when using <25% fill PLA. Less pronounced positive environmental results are observed with ABS, which demands higher temperatures for the print bed and extruder. Overall, the results indicate that distributed manufacturing using open-source 3D printers has the potential to have a lower environmental impact than conventional manufacturing for a variety of products.

General Design Procedure for Free and Open-Source Hardware for Scientific Equipment

“…By reducing the amount of material used, the environmental impact is minimized as the processing and transportation embodied energy are all reduced by the reduced use of material [43][44][45][46]. This can be done by eliminating non-functional bulk to designs, and, in 3D printed designs, minimizing infill percentage to fulfill mechanical requirements.…”

“…The use of distributed digital manufacturing using widespread and accessible tools such as the RepRap 3D printer and open PCB mills [47] help to reduce both the environmental impact [43][44][45][46] as well as reduce the economic costs of production [48][49][50][51]. Lead times can also be reduced, as well as improving maintainability.…”

Thermal properties of 3-D printed polylactic acid-metal composites

“…Considering the relative deviation from the filament raw bulk analysis, the results show the printing operation significantly impacts the resultant component density. Experimentally collected thermal conductivity values, however, do not correlate to the theoretical models in the literature and more rigorous quantitative exercises are required to determine true percent porosity to accurately model the effect of air pore volume for a lower cost of even simple products for the consumer [14], but a lower impact on the environment as well [15].…”

A low carbon footprint approach to the reconstitution of plastics into 3D-printer filament for enhanced waste reduction

“…Though deemed the best option for re-use of waste thermoplastics, recycling in its conventional form requires a relatively energy intensive process to form the end pelletised product for use in industrial processes, particularly the phase of plastic extrusion and granulation [2,5]. In response to this in an effort to reduce the environmental impact research groups are embracing the concept of distributed, or localised manufacturing, enabled through the use of open-source and low-cost 3D printing technologies [6]. 3D printing is a process by which 3-dimensional objects can be fabricated in a layer by layer building process [7].…”