Wave-generated
electricity tests setKaneohe Marine Base
may get power from
a buoy system offshore
Waters off Kaneohe will be used this fall to see if those nonstop open-ocean swells that make Hawaii a surfer's paradise can be tapped for cheap, clean electricity.
Ocean Power Technologies Inc., of New Jersey, holds a $9.5 million contract from the Office of Naval Research to test if the bobbing of subsurface buoys tethered to the ocean floor can efficiently generate electricity for Marine Corps Base Hawaii-Kaneohe.
AP PHOTO / OCEAN POWER TECHNOLOGIES VIA U.S. NAVY
The Office of Naval Research has contracted with a New Jersey firm to test the PowerBuoy wave energy power converter, shown in a graphic representation at left.
The idea is to reduce the Navy's electricity costs and dependence on oil at its shoreside bases around the world, but the technological development would also have applications for civilian uses.
"Everybody (at OPT) feels ... that we're doing something that may be important to the world," said George Taylor, president and chief executive officer of the 15-person company he helped start in 1994.
Taylor grew up in Australia where he learned to surf and appreciate the force of the waves curling around him.
The pilot project's first phase calls for one of the company's trademarked PowerBuoys to be given a buoyancy to ride nine to 12 feet below the surface in 100 feet of water nearly a mile off the Kaneohe base's Hilltop housing area.
As the swell passes, the 40-foot-long, 15-foot-diameter, vertically positioned PowerBuoy moves up and down on a rigid pole anchored to the bottom.
The up-and-down movement mechanically creates a flow of hydraulic fluid to drive an electrical generator housed in a canister on the ocean floor, said Don Rochon, spokesman for the Pacific Division of the Naval Facilities Engineering Command, which is overseeing the project.
The motor generates direct current in a submerged cable to an onshore transformer to create an average 20 kilowatts and up to a peak of 50 kilowatts of alternating current plugged into the base's Hawaiian Electric Co. grid, enough to serve five to eight homes, Rochon said.
Several prototypes of the system have been successfully tested off the New Jersey shore in Tuckerton since 1998.
Project operators are waiting for lower swells usually occurring in September to place the subsea electric cables, after which the PowerBuoy will be deployed, Rochon said.
The only visible part of the device will be a brightly colored navigation mast sticking up to warn boaters to avoid coming too close.
The contract calls for a second device to be deployed and for a two- to five-year test period to see if the project will be expanded for permanent use, Rochon said.
"First, we have to prove the technology," he said.
Hawaii was chosen for the test because on average it has the highest recorded wave power in the world.
The company said that in its technology, bigger is better.
If it can develop a 100-megawatt system, the company said its PowerBuoy technology can lower the cost of generating electricity to 3 to 4 cents per kilowatt-hour, slightly cheaper than electricity generated from fossil fuels and much cheaper than wind or solar energy systems.
A 1-megawatt system, the goal of the Hawaii project, would generate power at a cost of 7 to 10 cents per kilowatt-hour, including maintenance and operating expenses as well as amortized capital costs of the equipment, the company said.
A modular system based on an array of the small and relatively inexpensive buoylike structures would require low-cost maintenance for a lifetime of 30 years, according to OPT's Web site.
"We believe that this project will position the company for expansion into the U.S. and the international commercial marketplace," Taylor said.
To explain the global potential, the company's chief financial officer, Charles Dunleavy, said waves passing through a 10-by-10-mile area of ocean create enough energy to meet the electricity needs of the entire state of California.
