National Laboratory Researchers Test More Efficient Way to Build and Power Wave Energy Converters

Researchers at Sandia National Laboratories (Sandia) proved that taking a co-design approach to building a wave energy converter (WEC)—or designing the body and control system of the WEC at the same time—results in a more durable, powerful, and efficient device. 

Traditionally, the WEC body and control system are built separately—the WEC body is created first, followed by the control system. However, this approach does not consider how WECs are controlled in various conditions, such as rough or calm waves, in the ocean. By building these elements together, developers can create a better-performing device.

Researchers also used a magnetic spring, a mechanism that powers WECs, designed at Portland State University to generate more energy at a lower cost compared to more traditional mechanisms. The magnetic spring replaces the traditional powering systems, serving as the "engine" of the turbine. Because it operates based on magnetism, the magnetic spring does not wear down as quickly or have the issues that can emerge in a device operating with mechanical gears. The team found that this magnetic approach reduces friction, which increases the efficiency of the WEC. Additionally, the design for the magnetic spring is simple, cheap, and applicable to a variety of WECs, which will allow marine energy stakeholders to replicate it in many of their devices.

During tests conducted in a lab, the team found that combining the magnetic spring with the co-design approach resulted in a more optimized and durable WEC. As the team moves toward the next phase of the project, they are preparing their findings for public release so marine energy developers can apply the approach to their WEC designs.