Wave power developer Ocean Power Technologies has achieved the first ever grid connection for a wave energy device in the United States.
BY JAMES CARTLEDGE — It said today that the connection was achieved at the Marine Corps Base Hawaii, demonstrating the ability of its PowerBuoy technology to produce grid-quality renewable electricity.
New Jersey-based OPT has been developing and testing this particular 40-kilowatt device, a PB40 PowerBuoy, with the US Navy since December 2009.
The technology involves a buoy that is tethered to the sea floor, with a floating section that rises and falls with the surrounding waves to drive a piston-like generator system.
The Hawaii project aims to test out the technology’s reliability and capabilities to survive ocean conditions while successfully interconnecting with the grid serving the Marine Corps base.
Since its deployment in a site with 100-foot sea depth three quarters of a mile off the coast of Oahu, the PB40 has been put through 4,400 hours of operation, producing power from more than 3 million power take-off cycles.
Charles F. Dunleavy, Chief Executive Officer of OPT, said, “OPT has been ocean-testing its technology in the Atlantic and Pacific Oceans for several years. Our engineers and marine operations personnel have worked hard to bring about this success.
“Grid connection is another significant milestone in demonstrating the potential for commercial status of our PowerBuoy technology. We thank the Navy and the Naval Facilities group for supporting this project as we move nearer to achieving their goals for the program,” added Mr Dunleavy.
OPT’s grid interface system was originally certified as compliant with national and international standards by the independent laboratory Intertek Testing Services back in 2007.
OPT said its system has numerous on-board sensors to monitor performance variables and external conditions. Data is transmitted ashore via a fiber optic cable embedded in the project’s submarine power transmission cable, then sent via the internet to the company’s head office in Pennington, NJ.
So far, the company says its PB40 has been comparing well with the expected system performance as assessed by computer modeling.
The performance serves to confirm OPT’s models for its forthcoming 150-kilowatt device, the PB150, it said.
The wave power project at the Marine Corp Base Hawaii has involved local Hawaiian subcontractors for installation, testing and servicing, including Sea Engineering Inc.
OPT said the project has undergone an “extensive” environmental assessment by an independent environmental firm, in accordance with the National Environment Policy Act (NEPA), resulting in a Finding of No Significant Impact (FONSI), the highest rating assigned for such a project.