NEWPORT — As competing wave energy companies tout the virtues of their futuristic machines, researchers from Oregon State University are hoping to answer some basic questions about this emerging clean energy technology.
Questions such as: Will it really work? And just how clean is it?
On Thursday, scientists from the Northwest National Marine Renewable Energy Center at OSU demonstrated a new $1.5 million testing device called the Ocean Sentinel, which they hope will provide some answers.
Resembling a bright yellow dock equipped with an array of measuring instruments, the Ocean Sentinel floats on the water’s surface and is currently set up in a 1-square-mile test site, marked by buoys, 2 miles northwest of Yaquina Head off the Oregon Coast.
The OSU team recently began using the device to test a new design from Wave Energy Technology-New Zealand, which hopes to move into the U.S. market through a partnership with Portland-based Northwest Energy Innovations. As one of the first public wave energy testing facilities in the United States, the Ocean Sentinel is designed to provide data for both private industry and academic researchers.
Sean Moran, manager of wave energy ocean test facilities for the Northwest National Marine Renewable Energy Center, said that before addressing issues about the future of wave energy, such as its overall cost-efficiency, the project will first examine more fundamental questions.
“We’re taking a step back and figuring out why would you even go that far down the line if it is not a viable way to extract energy? Maybe it’s not as clean as we hope it will be,” Moran said. “We’re going to answer those questions.”
For this reason, the center decided to start small and use half-scale devices.
“It’s a way to fail fast and fail cheap,” Moran said. “We know we can generate energy, but can we generate energy in the winter? We don’t know.”
With onboard systems that monitor external conditions such as wind speed, wave amplitude and current strength, the Ocean Sentinel can be used to gauge the environmental impacts of wave energy devices, as well as their power output.
WetNZ’s design underwent preliminary testing at OSU’s Hinsdale Wave Research Laboratory in Corvallis before being deployed at the offshore test site. The $750,000 prototype, which is about 75 feet tall and 15 feet in diameter, is now connected to the Ocean Sentinel by an underwater cable.
The device extracts energy from the vertical rise and fall of ocean waves, as well as back-and-forth and side-to-side movements. It converts that motion to electricity by using a float on a central axle between two crossbars. As the float moves back and forth, it pressurizes hydraulic fluid that runs through a generator.
“At this stage, it’s a demonstration; it’s pilot scale,” said Justin Klure, program manager for Northwest Energy Innovations. “We’re not necessarily trying to prove commercial viability, but we’re certainly on that track. This is one step on the continuum to do that.”
The current testing period is scheduled to last through the end of this month. In that time, researchers are hoping to measure the performance of the WetNZ device in both high and low wave conditions.
“We’ll try to optimize the efficiency of the power conversion,” Klure said. “We want to understand loads, which is the forces that the waves are putting on the device.”