3D printing has a lot of potential impacts and uses in business. Prototyping to producing intermediates and making end use 3D printed parts are just some of the application areas where 3D printing is seeing large-scale implementations at the moment. One of the touted benefits of 3D printing is its ability to let companies produce in a more environmentally friendly way. How can 3D printing help companies go green?
Using Less Material
Compared to traditional manufacturing technologies such as CNC, 3D printing often uses less material to make the final part. Rather than starting with a one-kilo block of material and then cutting most of it away, 3D printing builds up an object layer by layer. This means that less material is used in the final part and less material is wasted. Just how much material is saved by using 3D printing depends a lot on the geometry of the part and what it needs to do. Individual 3D printing technologies also would work very differently, which would influence how much material can be saved. In some cases metal 3D printing instead of casting has saved manufacturers 20% or more in raw material. In using FDM (Fused Deposition Modeling, FFF) some industrial parts can be made that overall use 40% less material or more. There are knock on effects of this as well; using less material means buying less and storing less which also saves on shipping and storage costs. Aerospace companies often look at buy to fly ratios to determine cost advantages of parts. A buy to fly ratio is how much material that needs to be purchased versus how much material is used on the final part in the aircraft. 3D printing often comes out as a very advantageous technology when compared to others in this way because so much of the used material ends up in the final part. This is just one of the reasons why the aircraft industry is so interested in the technology.
Using Less Energy
Depending on the application, 3D printing can also save significant energy costs. If we compare metal 3D printing to traditional casting processes, for example, there is no need to operate a large industrial furnace or to undertake a series of moldmaking/casting steps. Depending on the type of furnace and the utilization of it, 3D printing metal should in most cases save on energy as well. Indirect 3D printing using a 3D printed cast or mold may also save on energy because a number of casting/molding steps may be skipped when using 3D printing. 3D printing plastic parts can also have energy savings when compared to traditional processes. This would depend, however, on the size and geometry of the part and how it is to be used.
One of main benefits of 3D printing is that lighter parts can be printed which have the same strength as heavier parts made with other processes. This can bring significant advantages to industries such as space, aircraft and the automotive industry. Part weight can be used to reduce the weight of aircraft, satellites, cars, drones, aero engines, trains and other craft. This would make them more fuel efficient, which at the same time is a significant environmental benefit but also a competitive one since the operating costs of the craft are lower than a heavier one. In the aircraft industry especially, lower weight aircraft outperform heavier ones and are cheaper to operate for the airline. Lower seat mile and higher buy to fly mean that any weight saved on the airplane through the part coupled with less material bought by the supplier will result in a lower cost per part and lower operating cost of the aircraft. These twinned reasons are very exciting to aerospace companies because they may be able to save money for themselves while saving money for their customers as well. Environmentally, of course using less fuel to fly as far is also very good for everyone, but the combination of: buy less material (I have lower costs), lower energy cost (I have fewer costs), lower weight parts (my customer has less costs) with less assembly, lower part count and quicker development times is what has the aerospace industry salivating over 3D printing.
NASA and Rocketdyne’s Baby Bantam 3D Printed rocket engine reduced part count significantly, from several dozen to three, while speeding up development time and lowering cost.
Lower Part Count
By using 3D printing you can make integrated parts. So a tube for example could be made with its brackets being 3D printed as a part of it. So instead of one tube and four brackets being made we only make one item, a tube with the brackets built in. This tube may then for example be 3D printed in such a way that it has a heat sink integrated in it, saving on more parts. Then we can make a complex tube which used to require four different molds to make. Now instead of four different molds, each requiring tooling and operation and stock, we only have one part. Reducing your part count significantly saves on material, weight and energy as well as assembly. Designing integrated components using 3D printing unlocks a lot of environmental benefits as well as cost savings. A lot less material is required through this approach and the environmental benefits can be immense. Today we’re seeing companies redesign parts for 3D printing but outside of aerospace and car racing we’re seeing rather little development in looking at entire assemblies and complex mechanics to reduce part count significantly in production. Lower part count is often overlooked by companies considering 3D printing as a technology. Once industries really come to grips with 3D printing, lower part count will bring significant and enduring economy to businesses.
Saving on Storage and Stock
If the above approaches are followed, a considerable saving on storage and stock will happen as a result of them. Much less material will have to be bought throughout the supply chain. Far fewer things will have to be kept in stock. Much less storage will result in considerable cost savings for companies. This will mean that they need less warehousing and waste less energy on warehousing. These knock on effects will also be multiplied as individual parts get optimally redesigned to make full use of 3D printing. In the above tube example, we’re reducing 10 or more parts to one. In some aerospace examples, part count was reduced from over a hundred to one. Imagine the environmental benefits in storage alone of something like that being replicated at scale.
Weight, Part, Material Saving in the Supply Chain
These weight savings also lead to savings on transport costs throughout the supply chain. Lighter parts and less materials that have to be shipped around lead to reductions in energy cost and CO2. They also mean operational savings for companies that adopt 3D printing, not only in the final part but throughout their entire operation.
By producing on demand, parts can be made when they are needed. This means that instead of making a million of something a year in advance you now 3D print the parts that are needed as they are needed. This saves on storage and for a number of parts would lead to a radical reduction in parts that need to be stocked. Just in time (JIT) production using 3D printing can be very operationally efficient for the manufacturer. The reduction in stock also means that less capital and space is tied up in stock. There is also less risk of unsold stock going to waste or having to be sold at a discount. Fewer wasted final parts and less storage of stock also translates to significant environmental benefits.
Manufacturing Close to the Consumer
By industrializing 3D printing close to the consumer, significant CO2 savings can be had by reducing the transport distances of parts. Supply chains often stretch around the world and any reduction in the transport of the final part significantly reduces transport costs and CO2. By manufacturing on demand close to your end customer you can also reduce the environmental costs of stock and respond more quickly to changes in your market.
Harvard’s Wyss Institute made a 3D printing material from discarded shrimp shells.
The majority of desktop 3D printers use PLA as a print material. This is very often thought of as an environmentally sound material. Whereas polylactic acid (PLA) is a biomaterial and therefore could have significant environmental benefits, it does use a lot of water. It is also a food source material, being often made from corn or maize. This would mean that it could make food prices more expensive. On the whole we can say that switching to bio-based materials and renewable plastics can provide huge environmental benefits for companies. It is important, however, to investigate just how beneficial these individual bioplastics are. It seems like a no brainer: use plants instead of oil to make plastic. The reality is a bit more complex.
Using Non-Food Source Biomaterials
Several groups worldwide are looking at making PLA from agricultural waste. Material that is usually discarded (such as corn husks, rice shells and shrimp shells) may be repurposed for PLA or other bioplastics. This would be a much more ethical material and bring significant advantages to the environment. More than 30% of food goes bad on its way to market and we may throw away 40% more in our kitchens. To repurpose this waste material and make plastic out of it would be very inexpensive and good for the planet. There are many pilot projects worldwide to make material that is suitable for 3D printing out of agricultural waste but they have yet to be commercialized in a significant way.
Using Compostable 3D Printing Materials
Another path forward is to make a compostable 3D printing material and to use this for parts, packaging or intermediates. PLA is to a certain extent compostable but new materials will have to be developed (or new grades) which will make bioplastic 3D prints more compostable. If your packaging from the supermarket or your packing crate can easily be composted then the environmental impact of your parts is greatly reduced.
Using Recycled Materials
Plastic bottles being recycled.
What is going on at scale is the recycling of materials such as PET, PETG or ABS. Regrind is often used to make 3D printing material. If not done properly or if the source is not well known or understood this could pose risks. But if it is done well then companies can not only use recycled material to 3D print but also recycle misprints or prints that are no longer needed. By not requiring new virgin material these recycled parts and materials are often good for the environment. Petroleum-based materials are often seen as evil but at the same time could be very environmentally beneficial if they can be reused several times. It is important to note that for many applications it is not the case that a material can be infinitely recycled. And of course a recyclable or compostable bio-based renewable material would be the most beneficial one. For 3D printing this does not exist at the moment although some vendors are experimenting with recycling PLA.
Using Waste Materials as a Filler
One can also use a waste or discarded material as a filler, adding it to a 3D printing material. This is especially helpful if that material is discarded by the manufacturer itself. Dutch Design Academy graduate Carmen Brio collected sea shells from restaurants. These sea shells are often discarded and just thrown away. They are however made of calcium carbonate, a material often used in construction and many other applications. She then ground down the sea shells and turned them into a 3D printing material on a 3devo filament extruder. Using the extruder, a PLA and sea shell 3D printing material was made. Instead of just regular PLA it now included a filler from a material that was previously thrown away. This meant that the material was even more sustainable and waste was turned into something useful. Depending on the industrial application many more people could, as Carmen Brio did, make 3D printing material from waste.
Closed Loop Recycling On Site
Several companies are working on shredders or recycling systems that do closed loop recycling on-site. You could then take your PET bottles and shred them and then extrude them into a 3D printing material. By doing this on-site, and using something usually thrown away, the cost per kilo of material would also be very low. Using a desktop or industrial filament recycler in this way, companies could save on 3D printing material cost as well as be green. Misprints or leftover material could be shredded once again and used (to a certain extent). Especially for institutions such as schools, universities or large office buildings, combining an in house recycling operation with 3D printing could have many green advantages. The company or institution’s own waste could become a 3D printing feedstock which will let things that they use be made on-site. This would be a huge potentially CO2 saving production system which, coupled with print farms, could let them inexpensively print parts out. On-site closed loop recycling is also the easiest “green 3D printing” thing to implement either with a materials vendor, 3D print vendor or with a shredder/extruder company.
What other ways do you know of that 3D printing technologies could be used to help production go greener?