HAWSEC wave energy device undergoes sea trials in Hawaii

March 24, 2023, by Amir Garanovic

Researchers at the University of Hawaii, with the help from experts at Gerard Nihous Consulting, have tested a small-scale version of Hawaii Wave Surge Energy Converter (HAWSEC) in real sea conditions.

HAWSEC wave energy device (Courtesy of US DOE/University of Hawaii)

The HAWSEC uses off-the-shelf or readily fabricated turbine components, which could make the design more cost-effective than other types of wave energy converters, according to developers.

The data collected on the device’s performance – which will be freely available to the public – could help guide the marine energy industry to create more cost-effective devices, a critical step to achieving commercial success, the US Department of Energy said.

A form of oscillating wave surge energy converter, the HAWSEC project contributes valuable data on how these devices perform, so other technology developers can learn from its efforts.

The HAWSEC is intended to be fixed to the seabed in shallow, near-shore waters. Positioned there, the device’s large, rectangular flap moves back and forth with ocean waves surging in and out. That motion then drives hydraulic cylinders to pump water through a turbine to generate electricity.

Prototype testing will allow the HAWSEC team to determine which of its two power take-off (PTO) designs, that convert ocean motions into electricity, might produce the most energy.

The team performed lab bench testing before heading to Oregon State University’s wave basin to validate the prototype in real waves and gather extensive data on the hydrodynamics of their flap.

For both lab bench and wave tank testing, the HAWSEC team received data collection support from experts at the National Renewable Energy Laboratory (NREL).

The HAWSEC team also collected motion data during a few hours of testing in the shallow waters off Makai Pier in Hawaii. These tests verified that the device and its data acquisition system, developed by NREL and called the Modular Ocean Data Acquisition (MODAQ), could perform as intended in a real-world ocean environment.

The team plans to complete testing of its smaller prototype, validate its numerical models, and after, build a larger prototype.