There’s been much ado made of the notion of “green” 3D printing, but is this really true?
The romantic notion of 3D printing greenness goes something like this: with a 3D printer, people (or companies) can immediately produce their object and thus avoid the huge energy costs of intercontinental shipping. Even better, certain plastics used in 3D printing are biodegradable (PLA) or recyclable (PETG, for example).
Those things might be somewhat true, but I think this leaves out a lot of the analysis. Let’s look at each of these aspects.
Is there less energy used when printing an object locally rather than using an object shipped from across the ocean? There’s two parts to this: the shipping and the printing.
In the case of shipping, it’s quite conceivable that the plastic used in 3D printing the object was itself shipped across the ocean! Perhaps it was in a more dense form than the target object, so the shipping of a spool of plastic filament might be a bit more efficient than the shipping of a final object.
In some cases the plastic is made locally, but will still require shipping from the factory to your location. Many times this will occur using air shipment across a continent, almost twice if using a hub-style distribution system. Air transport can be far less efficient than ocean shipping. In fact, I’ve seen statistics showing that a shipment from Australia to Los Angeles generates less carbon dioxide than a truck shipment from Dallas, Texas to Los Angeles.
So it seems that unless you are producing the plastic onsite or in a very nearby location, you may be less green than using a mass manufactured object, at least as far as shipping goes.
Oh, and you’ll have to consider that your 3D printer itself must be shipped. It’s only once, but it can be a substantial shipment.
But what about the printing itself? Isn’t that greener than a mass manufactured object. I think not. 3D printers are set up to produce one item at a time, and quite slowly, whereas mass manufacturing can produce dozens of items in minutes, maybe even seconds in some cases. Think of the duration of time required to provide energy to produce one object: it’s far, far less in mass manufacturing where an injection mold might produce a dozen items in 30 seconds.
So no, the print operation is far less green than a mass manufactured version.
And recycling? While these practices are theoretically green, I have written many times on the impracticability of recycling filament and don’t believe that will ever become sufficiently widespread to make a green impact.
Biodegradability? Yes, a few - not all - 3D printer materials are actually biodegradable. While I haven’t tried it myself, I’m told you can place a PLA print in a compost and it will eventually disappear. But let me ask you this:
When was the last time you put a PLA print in your compost? Do you even HAVE a compost?
I thought so.
3D printing, not quite as green as you might have thought.