Innovative, Economical Test of a Wave Energy Converter Using Land-Based Lab System Provides Promising Results

A multiyear component design and validation project between NREL and wave energy developer Columbia Power Technologies (C-Power) focused on the development and testing of the company’s WEC generator, and demonstrated the feasibility of safely conducting low-speed reciprocating tests of the generator using a traditional wind turbine dynamometer. Leveraging the capabilities of the lab’s 5-MW dynamometer, which is located far from the ocean in Colorado, NREL was able to validate that C-Power’s generator operated as designed, that no unexpected flaws existed in the mechanical, electrical, or control systems, and that the generator was ready for future tests in open waters.

NREL’s work supported C-Power’s efforts to build and test a novel, direct-drive PTO module, referred to as the “LandRAY” in a land-based test that simulated open-ocean operating conditions. A successful PTO module—essentially, the generator—is a key component to delivering cost-competitive wave energy. The LandRAY combined a large-diameter permanent-magnet generator with a patent-pending prototype localized airgap-reduction system. The project covered 12 stages of design, assembly, and testing, engineered to thoroughly characterize the PTO components by using overlapping data sets to isolate test results.

At the National Wind Technology Center on NREL’s Flatirons Campus, the testing and validation of C-Power’s device included mechanical system characterization, generator performance testing, real-seas simulations, energy storage performance validation, design and fault analysis, extreme-event testing, and noise monitoring. Overall, the LandRAY generator produced high-quality power that was smoothed by C-Power’s energy storage system—a critical performance landmark needed prior to open-ocean deployment and before connecting to the grid. Additional findings and outputs from the project, including applied methodologies, verification and validation techniques, and links to additional resources can be found in the final report.

For additional information, contact Al LiVecchi.