Additive manufacturing could turn the tides for marine energy technologies

Milk and cookies. Peanut butter and jelly. Macaroni and cheese. All delightfully good pairs. Researchers on the Nationwide Renewable Power Laboratory (NREL) found one other promising pair: marine vitality and additive manufacturing.

Since February 2022, researchers at NREL and the Pacific Northwest Nationwide Laboratory have been exploring how additive manufacturing may complement marine vitality applied sciences. Extra generally often known as 3D printing, additive manufacturing is a course of that makes use of skinny layers of fabric (like polymers, metals, ceramics, or others) to create a bodily object from a three-dimensional mannequin. A mannequin is created in a digital file, which transfers to the printer.

“In the very beginning, we quickly figured out that typical plastic additive manufacturing processes wouldn’t produce strong enough components to handle ocean forces,” mentioned Paul Murdy, a mechanical engineer at NREL and principal investigator for the marine vitality additive manufacturing research. “It became apparent that it would be impossible to design this structure without using metals.”

With assist from the U.S. Division of Power’s Water Energy Applied sciences Workplace to advance foundational analysis and growth for the Powering the Blue Financial system initiative, the NREL staff has been analyzing supplies and printing strategies for elements that make up tidal turbine blades.

By means of their analysis, specialists have decided that stainless steel (a corrosion-resistant materials) and laser steel deposition (an additive manufacturing methodology) are probably the most promising choices for fabricating tidal turbine spars.

However what precisely is a turbine spar? A spar acts as a spine for the turbine blade, holding the construction in place—which signifies that it’s a essential, load-bearing part. And these elements should be extra-durable for the ocean surroundings.

“We’ve opened a really unique design space through 3D printing,” Murdy mentioned. “This project has demonstrated that additive manufacturing has the potential to produce very strong, stiff structures that will be good for marine energy.”

Additive manufacturing may additionally deal with most of the challenges that marine vitality faces, like prolonged manufacturing timelines and excessive prices. For instance, additive manufacturing permits specialists to design elements with distinctive particulars—materials might be added and simply taken away elsewhere with out including manufacturing steps or impacting timelines. Due to this, builders can check a number of distinctive designs inside a a lot shorter time-frame and with a considerably decrease funding.

Advancing sensible and accessible applied sciences

Miguel González-Montijo, a graduate intern at NREL who’s incomes a doctorate in civil engineering, designed the turbine’s spar.

“I was interested in the spar geometry and wanted to ensure that the spar’s shape, size, and geometric intricacies matched an existing marine turbine blade design,” González-Montijo mentioned.

By designing a spar that can be utilized in present tidal turbine applied sciences, the staff hopes to allow fast prototyping of marine vitality gadgets. Having extra prototypes would permit for extra testing and design iterations, which might assist researchers determine probably the most promising applied sciences for blue economic system sectors, reminiscent of aquaculture or microgrids in coastal communities.

“For specific communities in particular places, marine energy could be a game changer,” González-Montijo mentioned. “For example, my home, Puerto Rico, could benefit from an upgraded energy grid that incorporates renewable energy technologies like marine hydrokinetic energy. These technologies could help many small towns build energy resilience and independence while delivering locally sourced, renewable power.”

Utilizing a mix of computer-aided design information (or CAD information) and state-of-the-art 3D-printing software program, components might be uniquely and particularly designed for various applied sciences after which printed to suit completely throughout the system. This system not solely permits researchers to plug and play, investigating which components work greatest for sure eventualities, but it surely additionally makes marine vitality far more accessible by broadly used design instruments (reminiscent of customary CAD software program).

Say, for instance, a coastal group installs a wave vitality converter to assist energy a microgrid, however a part wears out. With entry to a 3D printer, the native staff sustaining the gadget may import a CAD file, print the half, and substitute it.

In different phrases, additive manufacturing may assist construct resilience and vitality safety in coastal areas by assembly a group’s wants shortly. Reasonably than relying on provide chains or driving lengthy distances to get substitute components, additive manufacturing may give communities far more management over their vitality infrastructure.

Reaching the testing level

The NREL analysis staff is now testing their 3D-printed spar to validate the design and the instruments used to mannequin and fabricate the spar.

“Structural validation is critical to ensuring that the spar will react to real-life forces in the way that our models predict,” Murdy mentioned. “It also helps us understand how the novel additive manufacturing process differs from conventional steel manufacturing techniques and how we can account for it in future designs.”

The staff plans to carry out load testing by steadily rising the quantity of power and weight on the spar—maxing out at 1,900 kilos, which is 50% greater than what the spar is designed to deal with. Researchers will even carry out fatigue testing (i.e., repeating stresses and strains) to grasp how lengthy the spar would maintain as much as the intensities of the ocean surroundings.

“This test is the final piece for our research and will bring the project full circle,” Murdy mentioned. “We’ve been able to take an all-encompassing approach with this project: From theoretical modeling to materialized testing, we’ve exercised all of our capabilities.”

The NREL staff relied on Ai-Construct to manufacture the spar itself (which took a couple of week to print). Nonetheless, this venture proved that having the potential to 3D-print some of these elements would profit the laboratory’s marine vitality and water energy analysis at massive. Quickly, NREL researchers can have entry to a 3D printer that may fabricate comparable elements utilizing steel and different progressive supplies.

As soon as testing is full, the NREL staff will synthesize the outcomes and proceed iterating on the spar design. They will even examine different areas the place this methodology can additional marine vitality applied sciences.