In conversation with EOS’ Head of Sustainability, Björn Hannappel.
Sometimes, the idea that additive manufacturing (AM) can be more sustainable than conventional production methods, such as machining or injection molding, seems to be approaching the status of platitude.
“Well of course AM wins on sustainability,” one might say. “Just look at milling or turning, where the connection between generating waste and generating profit has been enshrined in its own old chestnut: ‘If you’re not making chips, you’re not making money.’”
And yet, the connection between AM and sustainability is not nearly so simple as this suggests. Does opting for 3D printing always mean using less material or less energy? More importantly, even if AM is more sustainable, how do companies weigh environmental costs against monetary ones? Do manufacturers care about sustainability when their success or failure can be measured in dollars or cents per unit?
To answer these and other questions concerning the relationship between additive manufacturing and sustainability, I sat down with the head of sustainability at EOS, Björn Hannappel, at this year’s RAPID+TCT.
Engineering.com: Can we start with a bit of your background?
Björn Hannappel: So, I started five years ago, and Marie Langer, our CEO, had just started only three months earlier. One of her goals was to establish sustainability as a central topic in the company, and that’s how my role was created. The project I worked on was to create a company purpose. Before that, we stood for innovation and technology, but there was no overarching mission. We conducted workshops globally to understand what our colleagues valued most and, across all regions, sustainability emerged as the top theme.
That led to our company purpose: to accelerate the shift to responsible manufacturing through industrial 3D printing solutions. That’s our North Star. Everything we do is meant to contribute toward that long-term vision.
For some perspective on sustainability and 3D printing, can you talk about the challenges, opportunities for polymer-based AM?
On the polymer side, one of the biggest challenges is waste powder. While we often say 3D printing only uses what’s needed, that’s not entirely true, especially with polymers. There is still waste. Fortunately, there are solutions now. New powders have much lower refresh rates, which enables our customers to have a more circular approach. Our newer generations of machines are also much more productive and energy-efficient.
We’ve also just started a reuse program for powder with Arkema called The Virtuous Cycle, where customers can sell their used powders to their recycling companies to be reused for different purposes. We did an LCA [life cycle assessment] on this because, when I joined, I said that I want us to understand how sustainable we actually are. Not so long ago, everyone in the industry was just saying, “Yeah, we’re good,” but without any real proof. That’s why our LCAs are externally verified.
For this reuse program, I questioned the sustainability of collecting powder globally and transporting it to Italy. So, we did an LCA with Arkema and Agiplast, and the result was positive: more than 7 kilograms of CO₂ saved per kilogram of recycled powder that’s sold. That was good news because we didn’t want to do something that just sounded sustainable but had a worse footprint after transportation and processing.
We’re also working with bio-based materials, like PA11 made from castor beans, which has a significantly lower carbon footprint. We’re also working on a biodegradable polymer that’s patented but not yet commercially available, though I just checked in on it and it should be ready soon.
Another opportunity is switching some applications from metal to polymer, and I’m talking here from a CO₂ and sustainability perspective. One very good example is a gripper that’s used in EV production. It used to be a 200 kg metal part but we redesigned it with Siemens into a polymer version that’s much lighter and made with our responsible materials. That change cut the carbon footprint by 90%, reduced lead time and cost, and allowed the use of smaller robot arms because it’s so much lighter. That means more robots in the factory so that overall efficiency goes up as well.
One more opportunity on the polymer side is printing what you need when and where you need it. We did a study with a startup in the eyewear space that focused on on-demand production and we were able to prove that 3D printing the frames is three times more efficient and emits three times less CO₂ than traditional methods of manufacturing those frames.
So, for polymers there are many opportunities but you need to look at them on a case-by-case basis.
What about metal additive manufacturing?
On the metal side, I think the biggest challenge we are facing is a lack of transparency in CO₂ emissions data. Powder production has a much higher carbon footprint, and it’s harder to get detailed information from suppliers because the market is more fragmented.
Another challenge is waste – less so than polymers, since metals can be reused – but there’s still waste that goes into the condensate. I think the biggest opportunity is increasing transparency, and we’re working on that. One of my colleagues is now focused on LCAs for metal powders. For some materials we have good, verifiable data; for others, we’re just beginning. We’re also collaborating with suppliers to use recycled sources, like aluminum, for example.
We now offer a carbon-reduced aluminum powder made from 100% recycled feedstock. It cuts CO₂ emissions by over 80%, bringing the footprint per kg close to the footprint of a polymer powder. Powder has the biggest impact on the carbon footprint of the whole application.
In the eyewear example, it was 75%, which is what prompted us to look at what we could do to reduce the footprint of the original powder, which led to the Virtuous Cycle program. This helps our customers lower their product footprints. Right now, we have two reduced-footprint powders for polymers and one for aluminum, and we plan to introduce more.
So, in some cases we’re talking about replacing metals with polymers, and in others you’re getting the metals closer to the same footprint. How do you decide between those two strategies? Does it just depend on the application?
Yes, exactly. The applications come from the customers. We do consulting – our Additive Minds group even does sustainability consulting – but it’s the customer who decides what part to use and how to optimize it. In the gripper case, the question was: Does it need to be metal? And the answer was no, so they switched. But we don’t usually make that decision. What I want to do is translate our company purpose into tangible benefits. Since powder has a high CO₂ impact, we’re working to reduce its footprint to help improve the footprint of the overall part.
What are the opportunities on the metal side? I think there are a lot, especially in energy-intensive industries like aviation and space. Every kilogram – even every gram – you reduce in the weight of a component saves significantly. But it’s not just about lightweighting. We’re also talking about functional integration, which is possible with 3D printing.
We have an inductor that’s used for heating parts during automotive manufacturing. Usually, you have an inductor made out of copper that gets really hot. You put the part in, heat it, then take it out and put it into a cooling liquid. With 3D printing, we worked with a customer to integrate that into a single part. So you have heating, and inside, there are cooling channels with small openings. Once the part is heated, the liquid comes out of the inductor and immediately cools it. It’s a fantastic case. Plus, it lasts much longer, so you don’t need to replace it as often. There’s a solid business case behind it as well.
I want to ask about measuring sustainability. You mentioned some successful life cycle assessments, which are easy to understand in the abstract, but what happens when you run into an LCA where the results just say, “No, this is not worth it,”?
Let me answer that from a few perspectives. One is internal, and the other is external. Externally, we want to provide benefits to our customers. I mentioned responsible products—we provide certificates to customers that show how much CO₂ they save. They can use that in their own carbon accounting.
Internally, we also account for CO₂. We’ve set up carbon accounting across all our operations, which brings transparency. Sometimes we discover things we didn’t expect—like a truck running daily between two locations regardless of whether it’s full. That kind of thing becomes visible only because of carbon tracking. Looking at our machines and powders, and the applications, we do life cycle assessments in cooperation with research institutes. But we’ve also trained 10 colleagues globally to do LCA themselves, since we believe it’s something we’ll need going forward. And we always get these assessments externally verified, which is required by the ISO standard.
I’m also part of a group working on a new ISO standard for calculating CO₂ emissions in our industry. The key question is: How? There are existing ISO norms for LCA, but the real issue is defining boundaries, choosing datasets, and knowing what data is acceptable or not. This is now a working group within ISO. In our industry, boundary setting is critical. Some customers want to compare a part made traditionally with one made additively. And in almost every case, traditional manufacturing uses less energy in the direct comparison. But the real benefit of additive isn’t in that one-to-one production comparison. If there weren’t additional advantages, you’d stick to traditional methods because they’re less expensive. Additive is used because of other benefits, often related to improved efficiency, which leads to CO₂ savings. A part might have a higher production footprint, but over its lifetime – in an aircraft, for instance – it could save tons of kerosene, which translates to money and CO₂ savings. You need to look at total cost of ownership. A cheaper part that consumes more fuel over time is not really cheaper in the end.
To your question, “What happens if it’s not better?” We had the eyewear study. At first, we didn’t know what the result would be. But a customer was interested, so we built the model. We were lucky to find a recent study on traditional manufacturing for a solid comparison. The result was positive, but we didn’t know that in advance. If it hadn’t been positive, at least we’d know where the challenges are and what to improve. That’s how we approach it. I don’t like greenwashing: just saying we’re better because it’s additive. Let’s prove it. And if we’re not better, can we improve?
What about cases where there’s tension between business objectives and sustainability goals? Obviously, those aren’t always in opposition, but I assume you’ve had times where you encountered resistance. How do you resolve that?
It’s a very good question and an important one because we need to have a common understanding. What helps us is having top-down commitment. Our CEO wanted this: she created my position, and that’s crucial. So, my approach is to explain things from an efficiency perspective. It’s not business or sustainability because they go hand in hand. If you save CO₂, you save materials, energy, and money. You become more efficient.
My role is to translate between sustainability needs (saving the planet) and business needs (financial performance). I need the right arguments if I’m talking to my CFO. So we need to find balance. We have a central team, but we’re integrating this mindset into all departments – procurement, transportation, material sourcing – so sustainability becomes part of everyone’s job. It’s no longer something you can or should cut.
Sometimes I frame it like this: If you just follow laws, you keep your license to operate. But that’s the bare minimum – no investment, no opportunity. Where we want to go is using sustainability as a license to grow. That means new products, new business models, more transparency, and better control. Yes, you need to invest, but you will see a return. That’s how I explain how sustainability adds business value. It won’t go away and it just makes business sense. My approach is to link it to that, not just tell people to do it because it’s “nice.” If you cut sustainability, you’re cutting into your own business.
You’ve been talking about the internal perspective at EOS. What about from an external perspective? Do your customers see sustainability as a priority or is it just a “nice to have” for them?
There’s no single answer. Some customers are really into it: the first adopters of our responsible products. There’s an extra cost, but they’re willing to pay because they’ve been waiting for better options. Then there are others who like the idea but don’t want to pay for it, but we’ve converted some of them through education.
Others have said, “I’ll just plant trees because it’s cheaper.” Planting trees is good, but if you’ve set science-based climate targets, you need to improve your own operations. Using our powders helps reduce Scope 3 emissions, which are usually the hardest to reduce. It took time, but they now see this as a real benefit, both for marketing and meeting internal climate goals. Then there are customers who just want transparency. They’re at the beginning, trying to learn what is the footprint of the machine, the application, our contribution?
So, there’s different levels but what’s interesting is that despite all the politics involved, the big multinational companies have been in this game for a long time already. They’re not backing away from it. And why? Because for them it’s about efficiency, not greenwashing.
