Between all the Yoda head prints there’s supposedly an element of sustainability built into 3D printing. At some levels it’s perhaps apparent, like rapid prototyping where casting a mold for an unfinished product is not efficient, or where 3D printed reef is transplanted to support an ecosystem. In other regards it’s hard to say how environmentally sound it is to run real time product debugging with numerous successive (buggy) prints; if it takes 34 prints to get a product right that’s quite a bit of waste, especially if everyone on the block has similar experiences. Currently, watt-for-watt, it takes more energy to print a good at your house with a personal 3D printer than it does to produce that good at an injection molding factory, and this is especially true of Selective Laser Sintering systems that suck large amounts of electricity. So if all that’s true, how is it that 3D printing is considered more sustainable than conventional manufacturing?

I’ve compiled this small list as a quick reference for those of us that could use a small, quick reference list concerning the current and future sustainability of 3D printing. When I reference the future in this article I’ll be referring to a date sometime around 2060, which is about as far as our proved global oil reserves will take us (1,800 billion barrels is predicted to last us some 50 years); more will be found but oil is costing increasingly more to explore and drill for because it’s deeper and deeper. After the oil is gone we’ll be left with a couple hundred years worth of natural gas and coal, but relying on that would be very unwise. I sure hope it doesn’t take us 50 years to be independent from fossil fuels, but I’m being conservatively pessimistic. The point is, in this hypothetical future renewable energy is ubiquitous. Why?

6. 3D printing will make renewable energy more accessible

While photovoltaic cells aren’t being printed currently, there’s no reason that technologies that enable printing at the molecular level couldn’t be convinced to print them. Solar-watt prices have dropped more than 50% over the past five years and new ways to create photovoltaic cells pop up regularly. Project POCAONTAS is dedicated to exploring the potential in using carbon nanotubes for photovoltaics; this is certainly a future task of 3D printers, and the frames and structures that hold and aim solar panels can already be printed. While standard photovoltaic thermal efficiency hovers in the teens, research-level photovoltaic efficiencies have surpassed 40%, which is better than that of your car and nuclear power plants.

There’s currently an Instructable on designing and printing a wind turbine, so the future there seems obviously stellar. Thingiverse hosts the files for printing a steam engine, and solar energy can produce steam without the need of photovoltaics vie employing magnification or concentration; pulling electricity out of a steam engine is pretty much all your power company is doing anyway. When I read about high electricity costs associated with 3D printing my gut response is simply to encourage pulling more electricity out of renewable sources. 3D printing won’t just decentralize manufacturing; it will also decentralize energy. And about decentralized manufacturing…

5. Reduced and more efficient logistics will create less pollution

Conventional manufacturing requires excessive transportation due to raw materials having to go through several production centers to become end products. The factory that cuts sheets of metal usually isn’t the same factory that shapes them into doors, and painting happens on the other side of town. With 3D printing most of that pollution-spewing driving around can be eliminated through the creation of raw material supply hubs that distribute raw materials to local residents and 3D printshops that will operate similarly to Kinkos. Since it’s significantly easier to track inventories of a few raw materials than it is tracking inventories of millions of end products, such a resource network will respond more to actual demand rather than perceived demand, reducing (or eliminating) wasteful overproduction.

Concerning what will need to be shipped, vehicles of the future will be far more efficient; a super lightweight electric race car called Areion exists today in part thanks to 3D printing, so again it appears apparent that industry-wide disruption is nigh. With lighter trucks (and trains and planes) using more renewable energy and traveling fewer miles, CO2 emissions will continually be reduced per capita and eventually will start reducing in absolute terms. When people start buying their raw printing materials on their grocery trips then the logistics, and the pollutions of such, involved in the production of their printable goods are nearly brought to their lowest possible levels.

4. Efficiency will be printed into buildings

Structures large enough to walk around in have been printed and there’s more than a couple projects focused on scaling 3D printing to produce whole houses and office buildings. Due to less materials being used in construction, greater uniformity in materials used, higher consistency of quality execution, and more control over design, future buildings will be markedly more efficient than the drafty boxes we currently call homes. Solar heaters and coolers can be incorporated right into the roof and walls, as well as other renewable energy catchers like wind turbines and geothermal heat pumps.

Building houses out of lumber and nails requires constructing temporary scaffolding that’s often not reusable; the scaffolds of future houses will be the printers themselves and will simply be transported from one construction site to the next and building no more than what will be lived in, which further reduces logistics. Walls printed in one material will be more efficient than the concrete, wood, fiberglass, and plaster we sandwich together now because they’ll be seamless, multiporous, and of complex geometries specially designed to keep the weather outside. As printing buildings will require less time as well, construction material inventories will have shorter cycle times, lowering loss of materials and operating costs. And when we’re printing houses, why not go ahead and print 3D printers into them?

3. 3D printing has the highest stuff-from-material ratio

Sure, SLS style printing burns loads of electricity, but the amount of mass consumed in the process is far less than other means of manufacturing. Intricately shaped objects often are beyond the capabilities of those other means, so expending more energy to achieve a more efficient object could result in a gain in net energy available. Besides, mass is the more limited resource as energy can, is, and will be pulled literally out of thin air. When 3D printing was in its infancy there was just as much error as trial; software and hardware hadn’t been refined much so more objects took more prints to get right. The great leaps in functionality standardization of 3D printing have resulted in more first-print successes and indicate an improving trend. This is an area where both technological innovation and user responsibility play roles in the sustainability of 3D printing; software will become more intuitive and hardware will be more precise and reliable, but it’s still up to you to take the time to perform due diligence on your prints and ensure you’ve designed them correctly. However, the future looks bright for all the unfortunate outcast prints that don’t make the cut.

2. 3D printing promotes recycling, upcycling, and repairing

There will always be some amount of junk prints, and many good prints need supports that are removed and discarded. Plastic piles can accumulate quickly but the future is poised to process plenty of piles. The Kickstarter success of the Filabot means we should have the market version of a plastic reclaimer in early 2013, as the Kickstarter orders are anticipated to go out before New Year’s. You may not have heard of the the Filabot Wee though, which is a chopped down and open-source Filabot entered into the Desktop Factory Competition hosted on iStart; the objective is to build an open-source plastic extruder for $250. And there are more open-source plastic extruders being created. Spooled filament costs several times more than plastic pellets per pound, and by combining different colored pellets more colors become accessible than through buying filament. The recycling of plastic piles into new objects has the potential of having an even greater positive effect on the sustainability of 3D printing, because no longer will bad prints and support materials be considered waste. They’ll just be expenditures of time and energy, so as long as the reclaimers are powered by renewable energy then the conversion of support materials, broken prints, or any other plastics into filament will be at worst a net-neutral event and usually a net-positive one.

Beyond direct recycling, 3D printing gives leverage to repairing. A lot of our goods have pieces that can be produced on personal printers, like knobs, buttons, gears, hose couplers, and loads more. In the future companies will offer the digital files of the printable parts of their goods, just like Teenage Engineering is doing with their OP-1 synthesizer. Sometimes Average Joe becomes Handyman Jim when the part is available, and in this regard 3D printing is adding some ‘Can Do’ to the mentality of ‘Why pay for labor when I can do it myself?’ by including parts too. If there’s no necessity to visit a retailer for a replacement part by just printing it, I feel there’s some hidden encouragement (embarrassment) there to avoid also the calling of a technician to install it by doing some How To DIY internetting (protip: YouTube is a goldmine). As the means and knowledge to repair become more accessible it seems only natural that people take it upon themselves to fix more of their broken stuff. All this repairing increases the average life expectancies of consumer goods, thus lowering the amount discarded. In the future robots and biomechanical engineers will fix most of our malfunctioning wares and recycling will be executed in an entirely different manner; many discarded objects will likely be reduced to their base elements on site for reconstitution later.

If you’re not familiar with upcycling, it’s the repurposing of what might have been discarded and/or the improving upon what still functions, and 3D printing is already making an impact here. Samuel Bernier included in his Project RE a demonstration of the potential of 3D printing in upcycling by printing lids that turn bottles and cans into hourglasses, birdhouses, citrus juicers, and a dozen other things. The Free Universal Construction Kit serves to bring interoperability between 10 of the most popular toy building systems, meaning Lincoln Log houses can have K’Nex powered Lego garages. How I wish I were eight again. It’s difficult to predict the future of 3D printing and upcycling besides pulling even more functionality out of our goods by them being designed to be added to and modified on the go.

Another worthy mention is the 3D printing material called PLA (Poly Lactic Acid), which is a bioplastic derived from corn, tapioca roots, and sugarcane. While it’s not currently easy to recycle, it is biodegradable and renewable, so it’s generally considered more sustainable than the most common 3D printing materal ABS (Acrylonitrile butadiene styrene), so many prefer it and the MakerBot Replicator 2 is optimized for its use. Currently the production of bioplastics results in an increase in the cost of consumer foods, as do biofuels, which is a negative social effect, so this is an area where 3D printing needs to enable major efficiency gains in order to achieve net-positive sustainability status.

1. 3D printing will enable major efficiency gains in food production

You may not like that a lot of our food is genetically modified, but it is. The future will likely follow a similar trend as it relates to printing food. Modern Meadow aims to print meat from real animal tissue grown in labs to avoid mass raising, slaughter, and transport of livestock. Raising livestock is one of the most pollution-creating industries due to the large amounts of feed, water, and space required, as well as the excessive amounts of methane and sewage produced. You may not feel comfortable eating printed meat but there’s a good chance that your grandchildren will find it commonplace.

Aside from printing meat, 3D printing will impact agriculture in many ways. There are already simple garden applications, but Japanese plans to construct a partially automated farm on some tsunami ravaged lands will in the future be executed through 3D printing. Additionally, Sun-facing sides of homes and buildings can have vertical garden systems printed right into them. There’s already a noticeable shift occurring in the preferences of consumers for more local foods and I see 3D printing helping to meet increased future demand. The Kontinuum Garden is an open-source 3D printed hydroponic system that’s super efficient because of its rotational design. Technologies such as these aid in getting food production into our neighborhoods and will have a dramatic positive effect on the sustainability of city living, as shipping food around is rather inefficient for those that can be grown locally.

People seem determined to apply 3D printing to as much as possible and this is resulting in some seriously sustainable innovation. The evolution of 3D printing looks to be a clean one when considering the breadth of its umbrella and how many hands are holding it up.