Is 3D printing really eco-friendly?

3D printing has been hailed as the catalyst for the next industrial revolution and the “democratisation of manufacturing”, being viewed as having the capacity to shift manufacturing to a more local level – from mass-production to mass-customisation.

However, in reality the balance of pros and cons is more complex, and the technology is unlikely to have as strong an influence on traditional manufacturing as many sources have suggested.

The balance of lifecycle impacts of 3D printing has been investigated in some initial studies in the area, with the conclusion that electricity in the in-use phase is the dominant environmental impact. However, there are many uncertainties and variations in such analyses.

Whether 3D printing has lower or increased environmental impact to alternative manufacture methods depends which manufacture technique the 3D printer is replacing and the impacts being taken into account in the assessment.

For example, a UC Berkley study found that 3D inkjet printers had significantly worse ecological lifecycle impacts than traditional CNC (computer numerical control) machining for the high-production scenario they investigated, but that an FDM-style (fused deposition modelling-style) 3D printer had significantly lower impacts than CNC, and that injection moulding outperformed all the other options in terms of environmental impacts.

Dramatic forecasts of industrial revolutions where mass manufacture is replaced by localised 3D printing should be viewed
with some scepticism – it is not something that is likely to happen in the short to medium term, due to current restrictions in materials, cost and usability.

The feasibility of 3D printing as an alternative to traditional production methods will depend upon the specific application. 3D printers facilitate the production of highly customised parts, but at the expense of production time and cost, and are therefore best suited to small production runs. There is also the issue of dimensional instability in the production of high-strength parts, which represents a significant barrier to larger scale adoption of the technology.

Despite these limitations, 3D printing will continue to find niche uses in the short term and sustain growth in the industrial (rapid prototyping, mould production and applications where reducing part weight is a priority), retail and after-market support (print shops and spare parts servicing), Biomedical (patient customisation) and low-end consumer areas.

The use of electrical energy appears to be the largest environmental impact of 3D printers, but waste is still important, particularly as it represents a proportion of wasted energy as well as materials.

In terms of the comparative environmental impacts of mass production versus 3D printing, these will depend upon the process being replaced, the 3D printing technology, the production volumes required, and the material type used.

There is scope for considerable improvement in the environmental impacts of 3D printing. The starting point can be a proactive consideration of environmental factors from the outset of manufacturing process/product design.

Greater research  comparing economic and environmental impacts of different printing approaches and highlighting suitability of processes to specific design requirements could facilitate a shift toward lower impact 3D printing and maximise the potential of 3D printing to liberate designers from the boundaries of traditional production.