Printing hardware is considered as either an industrial or desktop technology. Using the same fundamental processes, industrial printers are capable of greater accuracy, quality, volume, and batch size compared to desktop versions. As the use of additive manufacturing (AM) grows over the coming decade, it is important to consider the environmental impact of 3D printing in the industrial and desktop industries.
Industrial Printing
Review of Traditional Methods
Industry experts forecast industrial 3D printing will catalyze a new revolution in manufacturing. With promising applications in prototyping, tooling, and end-use constructions, additive manufacturing (AM) is set to offer a more time and material efficient alternative to traditional manufacturing methods. In addition to its practical strengths, additive manufacturing has the potential to solve some of the environmental concerns standard in current manufacturing processes. Material and supply chain inefficiencies frame two of the major pain-points of traditional methods.
Current manufacturing heavily relies on subtractive technologies. During subtractive processes, machines remove material to produce the desired part. These technologies present obvious environmental issues. Subtractive machines remove and waste much of the raw material purchased for the construction. Heavily decentralized supply chains–common throughout traditional manufacturing–amplify these material concerns. Given the design and fabrication limitations imposed by subtractive methods, traditional supply chains require a massive network of global partners to handle the design, creation, and distribution requirements necessary to produce a final product. The complexity of traditional supply chains means serious environmental consequences, leading to a greater consumption of natural resources at every stage of the manufacturing process.
AM’s Solution
3D printing offers a unified solution to material and supply chain concerns. While traditional methods are “subtractive”, 3D printing is “additive”, generating only the material required for the final part. As a result, additive manufacturing manifests immediate material savings. 3D printing also promises to simplify supply chains, allowing the design, prototyping, and production stages to occur under one roof. Additive manufacturing allows manufacturers to reduce the number of outside partners needed to realize their product. This simplification would yield massive energy savings. While additive manufacturing offers environmental improvements over traditional processes, there is still concern over the environmental impact of 3D printing.
AM’s Shortcomings
Active energy usage remains an issue for 3D printing technologies. Printing methods can consume significantly more energy than traditional technologies like injection molding. This is particularly the case for laser and light based technologies like Stereolithography (SLA) and Selective Laser Sintering (SLS). Additive manufacturing has the potential to achieve energy savings of up to 64%. However, manufacturers must first address 3D printing’s energy inefficiencies in order to achieve a more holistic solution to manufacturing’s environmental shortcomings.
Desktop Printing
Energy Consumption
Desktop printing presents material and efficiency concerns as well. These environmental issues are a direct result of the scalability of desktop printing. Big-time companies like Carbon3D, Fusion3, and Formlabs are working to make technologies cheaper, faster, and easier to use. Printer sales are surging because of this investment. Manufacturers sold around 300,000 printers worldwide in 2015. In 2020, that number grew to 2.1 million and is expected to reach just over 15 million by 2028. Increasingly accessible prices are driving industry growth. While industrial printers can cost well over $100,00, desktop versions can cost anywhere from $200 to $6,000.
Millions of new printers are reaching homes, schools, and companies each year. As a result, the same environmental worries plaguing industrial printing are amplified on a much larger scale. Industrial forms do consume far more energy than their desktop counterparts. However, the incredible growth in printer usage enabled by advances in desktop technologies means greater energy consumption. More printers, more energy used.
Printing Materials
PLA
The growth of 3D printer sales also means the spread of potentially hazardous materials and practices. The media publicizes 3D printing as “revolutionary” and “ground-breaking”, but rarely discusses its sustainability. The environmental impact of some industry-dominating technologies should be in question. While PLA filament for Fused Deposition Modeling (FDM) printing, for example, is considered “plant-based” and “biodegradable”, the sustainability of PLA is overstated. A writer from the environmental research organization Sea Going Green describes a more realistic account of PLA:
“The biggest concern to PLA’s is the specific and necessary conditions that are needed for proper composting. Rather than being recycled with regular plastic materials, PLA must be sorted separately and brought to a ‘closed composting environment’….In almost every case PLA plastics end up in landfills or our oceans…In order for PLA to be a viable, ‘eco-friendly’ solution, proper sorting and industrial composting systems must be put in place.”
With printers being sent to an increasing number of ordinary consumers, the impetus to properly discard PLA is extended to millions of people who likely don’t care or don’t know how to properly dispose of their plastics. Considering most cities lack the resources and facilities to properly handle PLA, claims of PLA’s sustainability appear even less attainable.
Resin
Stereolithography printing also raises environmental concerns. Liquid resin, used in SLA printing, is naturally toxic. Alongside its harmful effect on human skin and respiratory systems, resin is particularly destructive to marine ecosystems. Users often improperly dispose of resin through liquid-waste systems like sink drains or sewage inputs, allowing plastic particles to reach oceans, lakes, and rivers. This malpractice adds to sea pollution and damages aquatic life as caustic chemicals enter the respiratory and digestive tracts of marine animals.
The same scalability issues threatening PLA’s sustainability compound the threat of resin’s toxicity. As SLA printing becomes more popular, it reaches a greater number of potentially irresponsible consumers who lack the knowledge to treat resin safely. While there are “bio-resins” that offer a more environmentally friendly replacement to traditional resins, they suffer from cost and quality issues that provide little incentive for consumers and organizations to make the switch.
Conclusion
While desktop 3D printing has promoted important technological innovation within the industry and offers a range of impressive civilian and commercial applications, desktop printing lacks the oversight and education necessary to scale the technology safely. Consumers must be aware of the dangers of the materials they use and must be taught proper disposal methods in order to reduce the environmental impact of 3D printing and promote sustainability. Cities should follow this action and provide the infrastructure necessary to properly discard PLA and resin, making sustainable printing practices an easy choice for their populations.