WASHINGTON D.C. – Developing technologies that harness the power of ocean waves to generate electricity holds immense promise for renewable energy. But before these wave energy converters (WECs) can power homes and businesses, they face a critical hurdle: surviving the relentless and corrosive forces of the open ocean. The National Renewable Energy Laboratory (NREL) is at the forefront of efforts to assess the survivability of these technologies, pushing them to their limits in simulated and real-world environments.
The ocean presents a uniquely challenging environment for any engineered structure. Constant wave action, powerful storms, corrosive saltwater, and biofouling (the accumulation of marine organisms) can quickly degrade materials and compromise the functionality of even the most robust designs. Understanding how WECs withstand these forces is crucial for attracting investment, ensuring long-term reliability, and ultimately making wave energy a viable part of the U.S. energy portfolio.
NREL’s research focuses on identifying the failure modes of WECs and developing strategies to mitigate them. This involves a multi-faceted approach that combines advanced computer modeling with rigorous physical testing.
"We're trying to understand how these devices behave in extreme conditions," explained Dr. Katherine Dykes, a lead researcher at NREL specializing in wave energy technology. "It's not enough for a WEC to generate electricity efficiently; it also has to survive years of exposure to the harsh marine environment."
One key aspect of NREL's work involves developing sophisticated computer models that simulate the hydrodynamic forces acting on WECs. These models allow researchers to predict how a device will respond to different wave conditions and identify potential weak points in the design. This significantly reduces the need for expensive and time-consuming physical testing in the early stages of development.
However, computer models are only as good as the data they are based on. To validate their models and gain a deeper understanding of WEC performance, NREL also conducts extensive physical testing. This includes tank testing, where scaled-down models of WECs are subjected to controlled wave environments in specialized facilities.
For example, the U.S. Navy's Maneuvering and Seakeeping Basin at Carderock, Maryland, allows NREL and its partners to simulate a wide range of ocean conditions, including extreme storms. By monitoring the performance of WECs in these simulated environments, researchers can identify design flaws and improve the robustness of the technology.
Beyond tank testing, NREL is also involved in supporting real-world deployments of WECs at various test sites around the country. These deployments provide invaluable data on how WECs perform in the actual ocean environment over extended periods. The PacWave South test site, off the coast of Oregon, is a prime example. This facility provides a grid-connected location where developers can test their WECs in a real-world setting and gather data on their performance and survivability.
One of the biggest challenges facing WEC developers is biofouling. Marine organisms, such as barnacles and algae, can quickly accumulate on the surfaces of WECs, increasing their weight and drag, and potentially interfering with their operation. NREL is researching various anti-fouling strategies, including coatings and materials that resist the attachment of marine organisms.
Corrosion is another major concern. Saltwater is highly corrosive to many metals, and WECs are constantly exposed to it. NREL is investigating the use of corrosion-resistant materials and protective coatings to extend the lifespan of WECs.
The data collected from these tests and deployments is then used to refine the computer models and improve the design of future WECs. This iterative process of modeling, testing, and refinement is essential for ensuring that wave energy technology can withstand the rigors of the ocean and contribute to a sustainable energy future.
Ultimately, the success of wave energy depends on developing technologies that are not only efficient and cost-effective but also durable and reliable. NREL's research plays a crucial role in helping developers achieve this goal, paving the way for a future where the power of the ocean is harnessed to meet the nation's energy needs.
