Wave Energy Technology Could be the Next Big Thing in Renewable Energy
The search for renewable energy sources is becoming more prominent, and a distributed embedded energy converter designed by the National Renewable Energy Laboratory looks promising for wave energy harvesting.
The renewable energy search is becoming more prominent as the world pushes toward a sustainable future. A recently secured patent for distributed embedded energy converter technologies (DEEC-Tec; “deck-tech”), a domain designed by the National Renewable Energy Laboratory (NREL), is a promising opportunity for wave energy harvesting.
Marine Renewable Energy
Unlike other ocean energy-harvesting solutions, which consist of one energy-harvesting module, the DEEC-Tec domain is unique in combining many individual energy converters to create a larger structure. One primary advantage of this architecture is that using an array of tiny converters makes the structure more flexible. With a flexible geometry, the DEEC-Tec system can bend and conform to different shapes, allowing it to interact with an energy source across its entire structure.
Example of a “snake” DEEC-Tec. Image used courtesy of Offshore Energy
These flexible ocean wave energy converters are often referred to as flexWECs. With the ability to be built into numerous shapes—snakes, balloons, paddles—flexWECs increase the potential for substantial marine energy generation because more of the device can be used to extract energy from ocean wave movement. The individual energy converters that create flexWECs generate energy through movement in the structure, which is possible because the DEEC-Tec-based devices are built without mechanical joints. Wherever water movement causes the dynamic structure to deform (twist, bend, or move), energy can be harvested from the deformation at that location.
Stronger Than Traditional Wave Energy Designs
Traditional wave energy converters experience their own construction, maintenance, and cost challenges. In water, the structures are under constant stress from wave pressure. While this is great for harnessing energy, with only one converter, there is a greater risk of damage or failure because the force isn’t spread out. To minimize this, the structures are often built with inflexible steel frames. Unfortunately, the materials can be costly and not sustainably procured, in addition to raised costs for regular maintenance to fix operational failures.
DEEC-Tec concepts used in the FlexWECs design, on the other hand, have a natural redundancy and robustness because of the many small transducers used to build the structure. Here, the wave forces are distributed across all elements, leading to lower pressure per element and a lower risk of failure. Additionally, the failure of a single converter or group of converters does not automatically create a failure of the whole FlexWECs structure.
Because of these improved properties, the materials and assembly costs of the domain are relatively low. They are mostly made from common polymers and fabricated in a simple roll-to-roll process. The simple design also allows for the structure to be easily maintained, installed, or stored, depending on need or to avoid damage from ocean storms.
DEEC-Tec can also be used as a sensor within the structure, decreasing maintenance schedules by tracking real-time information from the transducers.
Future Renewable Energy Generation Possibilities
While the patent was issued for using the DEEC-Tec domain for marine energy, Blake Boren, Senior Engineer and Lead Inventor at NREL, says the domain has legs to expand its use on land.
Because DEEC-Tec generates energy through dynamic movement and can be combined to create a larger structure, the domain could also be used to make fabrics, barriers, and building structures. This dramatically expands the range of use for DEEC-Tec-based energy-converting structures.
Imagine if your phone could charge in your pocket as you walk, lights could be powered by the sway of a building, or roads could generate energy from the cars driving over them. The resilience and flexibility of the DEEC-Tec domain open it up to create new possibilities for generating renewable energy.
The NREL team has made many advancements in the DEEC-Tec domain and still recognizes the challenges they face with the design. Proper materials are necessary to mitigate fatigue, determine optimal geometry structure, and enhance power conversion efficiency. They are optimistic these challenges will be solved.
Updated as of December 7, 2022: Japanese naval officer Yoshio Masuda and his experiments in the 1940s pioneered the study of wave energy as a power source. Masuda conducted tests on a variety of concepts, built hundreds of units to provide power to navigation lights, and produced a navigation buoy powered by wave energy. Regarded as the father of modern wave power technology, he also has been credited with inventing the principle of the Oscillating Water Column.
Featured image used courtesy of Adobe Stock