With the acceleration of global warming and other factors like pollution and industrial fishing practices critically destroying and endangering coral reefs and coastal ecosystems around the globe, it has never been more critical to develop solutions that can help to restore these fragile yet incredibly diverse environments. Fortunately, there are people and organizations who have taken up this challenge and are finding creative ways to not only save coral reefs and other coastal environments, but also usher us into a more sustainable, ecologically minded future. One of these organizations is Coastruction, a Dutch startup that is leveraging its own 3D printing technology to build aquatic structures that are designed for a range of restoration purposes, like promoting coral regeneration and wave dissipation.
Coastruction, which is celebrating its third anniversary this month, was founded by Nadia Fani, who has a background in computer science and 3D printing. Over the past few years, Fani has put together a dedicated team of eco-enthusiasts trying to build a better future, including Josine Beets, Coastruction’s Project & Business Development Manager, who herself has a research background in nano-biology and bioprinting. We had the chance to speak with Beets about Coastruction’s overall mission, its unique technology and the various coastal restoration projects it is participating in.
From Idefix to Asterix
Coastruction founder Fani started developing 3D printing systems in 2015. In 2018, she built a small desktop system, which eventually evolved into the Idefix platform, a standard-sized 3D printer that deposits water onto a print bed consisting of a mixture of sand and cement. “What we have is a powder bed 3D printer, with a box filled with dry material and then you deposit water selectively on each layer, which acts as a binder,” Beets says.
Image: Coastruction.
Since January 2024, Coastruction has rolled out the latest generation of its 3D printing technology, the Asterix, a larger system with a build volume of one-cubic meter. Instead of a single nozzle, like the Idefix, the Asterix is equipped with 88 nozzles that selectively bind the sand and cement mixture.
“Every layer the print bed lowers and a new dry layer is applied and water deposited,” Beets elaborates. “At the end, you have a big box filled with powder: some hardened and some loose. From there, you can remove the entire print bed (it is on wheels so can be transported and replaced easily) and set it to cure overnight.”
This initial curing process, which involves leaving the entire print box to sit for a night, ensures that the bound cement particles can settle and that prints are solid enough to be removed from the loose powder print bed and vacuumed. (The remaining loose powder can then be reused in a future build.)
From there, Coastruction’s production process involves placing the cement prints, which can measure up to a meter in size, outside, where they continue to cure. “The prints have to be moisturized,” Beets specifies. “So we pour water over the structures every day, like watering your plants, and after seven days, they are strong enough to be lifted by ropes and transported.”
In some cases, like in a recent collaboration with a team in Saudi Arabia, the curing process takes longer to ensure that the artificial coral reefs are strong enough to survive long journeys, like from Rotterdam to the Red Sea. “We’re also looking into building a large pool where you can leave the prints to cure an entire day in water,” Beets says.
The relatively simple process, which does not use any toxic materials, results in large-scale cement structures that can be deployed in coastal areas. In terms of the cement materials used, Coastruction mostly works with CEM I, consisting of 100% Ordinary Portland Cement, and CEM III, which is a mixture of OPC and blast furnace slag.
“We have found CEM III to be a good option in terms of its environmental footprint, but the structures also have to be stable, so we are researching the difference between CEM I and CEM III. Sustainability is also about durability and there is still a lot of R&D going into this and we are always looking for students who want to do their graduation project on material sciences to find the best and most sustainable materials.”
Image: Coastruction.
Designing for reefs
Of course, the printing process is only part of the equation: design also plays a huge role in what Coastruction offers and how its prints are welcomed into aquatic environments.
“We have two design experts that we work with,” Beets says. “Carlos Rego is our biomimicry expert and designer, and David Lennon is an advisor on artificial reefs. They work closely with us on each project, looking to ensure that our solution is suitable for each location. We also have Sam van den Oever, our engineer who knows exactly what does and doesn’t work for the 3D printer. For example, you don’t want to design something that would be too fragile, but you also want there to be enough holes for fish to enter into the structure. Additionally, if you want to lift it with a crane, holes for a sling can be incorporated into the design. It all depends on the situation.”
Manufacturing on Demand
Coastruction’s design know-how and 3D printing technology are enabling it to build a variety of aquatic structures, from artificial coral reefs to eco-anchors. Whereas other industries emphasize the need for high-resolution prints and fine details, Coastruction’s builds are interested in the opposite. “We don’t aim to have a high resolution or a precise structure. We want to have a very rough surface and to be able to print big and fast.”
The Asterix platform prints with a surface roughness of 2.5 mm, which has turned out to be a surface texture that aquatic species are receptive to. “Mussels and algae love to grow on it,” Beets says. “We did testing in Hawaii, the Maldives and the Seychelles comparing our prints to other materials, and ours was one of the best. In another project, our printed structures improved biodiversity by 250%.”
Image: Coastruction.
Coastruction projects
This project Beets speaks of is based in the Netherlands and is being developed in cooperation with TouchWind and other partners. The project is centered on the development and deployment of floating wind turbines and Coastruction is 3D printing “ecological hybrid anchors” using its Asterix platform. In an early test to evaluate its 3D printed structures, Coastruction was pleasantly surprised at the results.
Beets explains: “Our structures improved biodiversity by 250% compared to the cast concrete blocks. There were crabs, fish and all sorts of species on our structures and nothing on the flat concrete surface, just barnacles. That is one of our best results to date and the biggest project that we’ve had results for.”
Elsewhere, other pilot projects and tests are also off to promising starts. For example, in the CREST project, part of the ARISE consortium, Coastruction tested 150 3D printed artificial reefs at the 300-meter-long Deltares Delta wave flume to understand their effectiveness in wave attenuation and their potential for mitigating flooding in coastal regions and islands. The tests were led by Marion Tissier, assistant professor of Ocean WavesTU Delft, who said: “I hope these insights will help optimizing the restoration design for coastal protection. This will ultimately contribute to improved forecasting tools for reef-lined islands that can be used to analyse future flooding scenarios and risk reduction measures.”
“I also think that the results of the Red Sea project we are working on now will be very significant,” Beets adds. “We are working with a team in Saudi Arabia, who will be researching and monitoring the effects of the 3D printed reefs, tracking the growth of coral and so on.”
In another recent project, Coastruction has been developing an eco-anchor in partnership with the Wave Energy Collective, a startup based out of the Hague that is engineering a wave energy converter. The project is progressing steadily, and Coastruction is preparing to deploy the first eco-anchors as soon as March. Already though, the Coastruction team has reported promising results. “We put one of our structures in the water at the port in the Hague to make sure the structure would hold its shape. After just a month, there were already mussels, sea stars and crabs on it, and this is in the port!”
Image: Coastruction.
On the horizon
With so many projects and tests in the works, Coastruction is also looking to the future, creating plans for a new 3D printing platform and a long-term business model. “Next year, we want to upgrade our Asterix 3D printer to make it fit in any environment and print with local materials,” Beets explains. From there, the plan is not to sell the machines outright but to function as a service, with Coastruction deploying its 3D printing solution around the world to its customers and key partners sending a specialist to train local teams. “We’ll also hire someone locally to take care of the projects,” she adds.
For example, a beach resort could hire Coastruction’s services for a year to restore a particular area of coastline. Coastruction would then research the location and design suitable reef structures. From there, a 3D printer would be deployed to the location, where local teams could oversee the production process and place the cement reefs into the water.
In addition to rolling out this business model, Coastruction is also developing an even larger 3D printer, the Obelix, a process that will hopefully be boosted by an investment or grant that Coastruction is trying to raise. According to Beets, the Obelix system will have a build capacity of six cubic meters and integrate a more automated workflow.
“Like Asterix, this 3D printer will be able to fit in a shipping container,” she says. “What I’m most excited about is to have a streamlined, automated workflow, with fully automated cleaning and curing processes. With AI-driven process monitoring, you’ll even be able to see how each layer is going and if something has gone wrong.”
Ultimately, Coastruction is doing some incredible things at its facility in Rotterdam, and has even greater plans on the horizon. We’re eager to see how the young company progresses and how its sustainable 3D printed reefs and eco-anchors can help to restore and maintain the at-risk coral reefs and coastline environments all over the world.
This article was originally published in VoxelMatters’ VM Focus Sustainability AM eBook. Read or download the full eBook for free at this link.
You might also like:
GLAMS project advances 3D printed lunar regolith structures: GLAMS, which stands for Geopolymers for Additive Manufacturing and Lunar Monitoring, is a two-year project that has the goal of developing structural components for lunar bases using 3D printing technologies and a lunar-regolith based material. Funded by the Italian Space Agency (ASI) and launched in 2023, the project brings together partners from across the country, including the University of Padua’s Center for Space Studies and Activities (CISAS), the Genoa-based Institute of Condensed Matter Chemistry and Energy Technologies of the CNR (ICMATE), and WASP, a 3D printing specialist based out of Massa Lombarda.
* This article is reprinted from 3D Printing Media Network. If you are involved in infringement, please contact us to delete it.
Author: Tess Boissonneault
Leave A Comment