Marine energy is a promising part of the renewable energy industry. It harnesses the kinetic energy of natural phenomena such as currents and tides and converts it into clean energy to power coastal communities. According to the U.S. Office of Energy Efficiency and Renewable Energy, Marine energy resources will account for 57 percent of total U.S. power generation in 2019. In other words, ocean energy holds great potential, and many innovative projects are underway aimed at advancing its development.
On May 7, 2024, researchers at the National Renewable Energy Laboratory (NREL), in collaboration with the Pacific Northwest National Laboratory, led a project to enhance ocean energy technologies using additive manufacturing, with a particular focus on tidal power, which uses turbine technology to convert energy from tidal water into electricity.
△3D printing tidal wind wing beam
Testing polymer and metal 3D printing technologies
Over the past two years, the project has been testing and analyzing various materials and printing techniques involved in the development and production of tidal wind wing beams. The wing SPAR is the load-bearing component within the fan assembly that holds the blades in place. The component must not only be able to support the fan blade structure, but must also be able to withstand the corrosive forces of the Marine environment. After some evaluation, the researchers found that thermoplastic 3D printing was not suitable for this particular application, and that the best options for producing tidal wind wing beams were stainless steel and laser metal deposition. Optimizing the operation of key components has proven critical to the success of major producers of Marine energy, such as offshore wind farms.
Paul Murdy, NREL mechanical engineer and principal investigator for the Marine Energy Additive Manufacturing Study, said: "We have opened up a truly unique design space with 3D printing. This project demonstrates that additive manufacturing has the potential to produce very strong, rigid structures that will benefit Marine energy."
NREL researchers Miguel Gonzalez-Montijo and Paul Murdy
The 3D-printed wind wing girder being developed by the NREL team is designed to fit into existing tidal wind turbine systems. The researchers say this could facilitate rapid prototyping of new Marine energy devices in various blue economy sectors, such as aquaculture and microgrids, to provide power to coastal communities. In the future, this will also make it easier for coastal towns and communities to replace worn parts in Marine energy systems by printing them locally, reducing their reliance on supply chains.
Miguel Gonzalez-Montijo, a graduate student intern at NREL who designed the part, said: "Ocean energy could be a game changer for a specific community in a specific region. For example, my home state of Puerto Rico could benefit from an upgraded energy grid that incorporates renewable energy technologies such as Marine fluid power. These technologies can help many small towns build energy resilience and independence while providing locally sourced renewable electricity."
The tidal wind wing beam is being tested using a hydraulic actuator
The results of the study will provide guidance for future design and development
Currently, the 3D-printed Tidal wind wing beam is undergoing testing at NREL's facilities, including fatigue tests and load tests of up to 1,900 pounds (said to be 50 percent more than the part is expected to withstand in a Marine environment). This iteration of the wing SPAR was 3D printed using AI-built robotic systems and stainless steel materials.
The 3D printing process takes about a week to complete. Montijo added: "Structural validation is essential to ensure that the wing SPAR can respond to real-life forces in the way our model predicts. It also helps us understand how the new additive manufacturing process differs from traditional steel manufacturing techniques and how we can consider it in future designs."
This test marks one of the final stages of the research effort, demonstrating the value and great potential of additive manufacturing in Marine energy applications. Following the testing, NREL researchers will continue to develop and fine-tune designs for 3D-printed wind wing beams and explore other potential applications of additive manufacturing in Marine energy.