As sustainability becomes essential in manufacturing, 3D printing has earned a reputation as an eco-friendly alternative to mass manufacturing. However, is it as beneficial as most people paint it to be?
3D printing is more sustainable than many subtractive manufacturing processes. It helps reduce waste, emissions, and energy expenses and promotes recycling. However, it also produces a unique set of waste. The process consumes much energy, and most 3D printing materials are not biodegradable.
The topic of sustainability has many facets. Thus, many are still debating whether the benefits of 3D printing outweigh the disadvantages. Still, if you keep reading, you’ll see why 3D printing holds hope for a greener manufacturing industry.
How Is 3D Printing Sustainable?
A method’s ability to reduce, reuse, and recycle is one of the essential components of sustainability. Many aspects of 3D printing allow it to do those three R’s (and more).
3D printing is sustainable because it is additive, unlike traditional methods. It reduces waste, recycles and reuses materials, extends product life, uses fewer resources, and minimizes transport and emissions.
So, let’s look at the factors of 3D printing that make it more sustainable than traditional manufacturing.
3D Printing is an Additive Manufacturing Process
The most significant advantage of 3D printing is its additive nature. This aspect makes it more efficient since it produces less waste than traditional manufacturing methods, like injection molding.
Conventional manufacturing methods are subtractive. They produce items in a technique similar to sculpting – they have a big block of material and take away parts to achieve the form they need. As you might imagine, there’s a lot of excess material. Thus, it’s less efficient, produces much waste, and takes time.
On the other hand, additive manufacturing builds layers. It rarely uses excess material because instead of taking away parts, it only adds what is needed. It’s like building using Legos – you only use the blocks you need and nothing more. Thus, it’s more efficient, uses less raw material, and produces much less waste.
There is great potential for recycling in 3D printing. You can re-make filaments from failed prints or supports. If the print material is thermoplastic, like PLA, it will be cleaned, shredded, and extruded to produce new filament.
If it’s metal printing, the unmelted, you can recycle excess powder by sieving and mixing it with fresh metal powder. However, metal powder recycling is still in progress, so many companies are hesitant to apply it. These companies need to ensure that the amount of metal in their products is verifiable, which is hard to achieve with recycled powder.
Reuses Other Materials
It’s not just the materials within the 3D printing world that are being reused and recycled. For instance, many 3D printing companies continually look for ways to use plastic waste as filaments. This initiative helps prevent the accumulation of stagnant waste in landfills.
For instance, Print4d is brainstorming ways to use waste in making 3D printing materials. On the other hand, 6K (previously Amastan Technologies) created the UniMelt process, which grinds scrap metal, 3D metal parts, and supports into metal powder used for printing.
6K also partnered with Relativity Space in the pursuit of making an actual space rocket from reusable materials. As ambitious as it sounds, the success of such a project would have a significant impact, especially since space projects are quite energy-expensive.
Another notable 3D printing project using reused materials is Deciduous, a 3D printed pavilion made for the Dubai International Financial Center. The Middle East Architecture Network project team used 30,000 reused water bottles and other materials to create this magnificent structure.
Allows More Optimal Designs
Traditional methods limit the kinds of designs produced. For instance, products need to be heavier or have different support structures. Manufacturers must assemble some product parts instead of creating an object in one piece.
With 3D printing, there are fewer limitations. The layered construction allows room for optimizing designs, making them more energy-efficient. For instance, you can design 3D prints that need less support or post-processing, leading to less waste.
One way to improve manufacturing designs is topology optimization. This process, which uses computer algorithms, allows for the creation of lightweight structures, which consume less energy to make and transport than their heavier counterparts.
While traditional manufacturing methods may find it challenging to produce light structures, it is possible with 3D printers.
This design advantage benefits many industries, such as transportation. For example, if manufacturers made cars and airplanes with lighter parts and materials, they would need less energy.
In traditional manufacturing, you cannot construct particular types of machinery in one large piece. To make items such as engines, manufacturers create subparts that will be produced individually and then assembled to make the whole. It is both time and energy-consuming.
However, in 3D printing, there’s more room for customization. That is, you won’t have to divide parts into smaller parts. You can optimize the design by using part consolidation or redesigning projects and machines so that you can print the whole piece with one print.
Part consolidation does not just take less time, resources, or energy. The reduced interface improves durability because, with less interface, there are fewer chances of damage.
Uses Less Resources
Additive manufacturing, recycling, reusing, and optimizing designs reduce necessary resources. Fewer resources mean less energy used and less waste produced, leading to a more sustainable process.
Making Items In-Demand
Besides those I already mentioned, another way 3D printing uses fewer resources is that manufacturers can avoid making items in large batches. Before, logistics and expenses made it so that it was better to produce objects in bulk.
However, if not all items in that batch were used or sold, they would get stuck in warehouses, or wherever excess supply is stored. This surplus is as good as waste, as it would take a while for people to buy or use them. Since these items require energy and resources to make, it’s also as good as wasted resources and energy.
With 3D printing, it’s possible to make items in small batches. You can create products only when they’re in demand or as custom orders. Thus, you can avoid spending energy and resources on surplus items.
Optimize Designs Before Construction
3D printing is the best innovation for prototyping. What you design is what you print. Thus, if you design products or houses for other people, you can always present the plan or simulation to them for feedback.
Then, you can apply changes until you achieve the best design. This editing and optimization help avoid later-on revisions and modifications, which could cost energy and resources.
Reduces Transport Costs
As I’ve mentioned, 3D printing allows the production of light structures, which take less energy to transport. Aside from that, it’s also possible to have vehicles made of more lightweight and optimized parts, which leads to less energy consumed for transport.
Besides those mechanisms, printing onsite is another way to reduce transport costs through 3D printing. Traditional manufacturing and construction usually involve the shipment of items from across states and even countries. With 3D printing, you can bring the printer onsite and create whatever you want without waiting for a delivery or shipping the final product.
Moreover, you can collaborate with other people abroad without traveling. You can send 3D designs online and have them send their remarks and feedback immediately, streamlining production.
Promotes Product Longevity
A great contributor to waste is items with broken parts. These products might have been disposed of because it’s too complicated or expensive to fix. However, if you could repair that part, you could extend the product’s life and use.
With 3D printing, it’s possible to repair items more quickly and cheaply. You just have to print whatever was damaged and reattach that.
It’s also possible to fix old things with 3D printing. Say you have a product with a broken part that the company no longer produces. Instead of throwing it out, you can 3D print the damaged part and use the print to replace it. This practice has even been used on aircraft and military vehicles, saving thousands of dollars.
One way to reduce emissions and reduce carbon footprint is by minimizing the need for transportation. With 3D printers that can print onsite and produce light structures, that is possible.
Aside from that, 3D printing construction companies are also looking for ways to reduce emissions. One specific company is Mighty Buildings, which works with Fortera to use cement created with 60% fewer emissions than traditional building methods.
Is 3D Printing Completely Sustainable?
It seems that 3D printing, with all the sustainability benefits it offers, is the perfect eco-friendly alternative to traditional manufacturing. However, the industry and process aren’t as perfect as it seems.
3D printing is not completely sustainable. Some of its materials, like resin, are hard, if not impossible, to recycle. The actual process of 3D printing also is energy-consuming, and it still produces waste and harmful emissions.
We must optimize 3D printing for safety and efficiency to achieve genuine and complete sustainability.
Some 3D Printing Materials Are Difficult or Impossible To Recycle
Although I did say that the 3D printing industry has great potential for recycling and reusability, some of the materials it uses are challenging to recycle or reuse.
These are some 3D printing materials that are hard to recycle:
- Resin. It’s impossible to recycle resin from 3D printing. 3D Printed resin has undergone structural changes during the process, and you cannot return it to its original state.
- Polymer powders. Selective Laser Sintering (SLS) requires the use of polymer powders. Similar to resin, the material had undergone changes making it challenging but not impossible to recycle. However, you can only reuse unfused powder, and you must mix it with new powder.
If you find recycling 3D printing materials tedious, some companies might be willing to do that for you. You may also opt to purchase recycled 3D printing materials.
Likewise, although materials like PLA have gained a reputation as biodegradable and sustainable for the environment, there is more nuance to that claim that doesn’t often make the headlines. Even “biodegradable” 3D printing materials take certain conditions to decay, and there are currently no compostable filaments available on the market.
To learn more about PLA and sustainability in 3D printing, I highly recommend checking out this well-made video from Maker’s Muse:
3D Printing Process Is Energy-Consuming
If you look at 3D printing solely at the actual process, it’s very energy-consuming. Some assert that 3D printing can consume 50 to 100 times more energy than traditional methods. After all, heating filaments to very high temperatures and piling them in layers can use a lot of electricity. However, this aspect of 3D printing is still under debate.
Aside from the energy consumed during the process, there’s also the energy used to make the 3D printing materials. For instance, the metal powder could have gone through many energy-consuming steps to create the powder used for printing.
Harmful Emissions May Be Produced By 3D Printing
Emissions are not just a safety concern but also a sustainability one. After all, how can something be truly sustainable if it’s harming us? Thus, there have been several studies to investigate 3D printing emissions.
These are some of the harmful compounds found to be released by 3D printing:
|Compound||Associated 3D Printing Filament||Harmful Effects|
|Caprolactam||Nylon||Irritates the respiratory system|
|Methyl methacrylate||PLA||Irritates skin|
|UFPs||All filament types||Respiratory and cardiovascular diseases|
More of these compounds are released at higher temperatures and in the presence of certain additives. Children may also be more susceptible to them.
3D Printing Produces Waste
Although 3D printing produces less waste than traditional methods, it still has some waste. Moreover, the produced waste, such as resin, requires unique waste management methods.
For instance, failed prints and supports are considered waste products of 3D printing. You can recycle them if you know how – otherwise, it’s good as trash. You can optimize your designs to use fewer supports to avoid excess waste.
Undoubtedly, 3D printing has great potential to become a sustainable manufacturing method. It is not wasteful, saves resources, is more efficient, and promotes the 3 R’s: reduce, reuse, and recycle. However, such potential would only be a waste if no one resolves the challenges that hinder it from becoming genuinely sustainable.