While renewable resources like wind and solar tend to draw the most attention, “marine energy systems” are also being developed as an alternative and complementary source of energy to help mitigate the effects of climate change.
One such marine system, wave energy, is in its early stage of technological development that requires large-scale testing before it can become commercially viable. Now, there is a new testing facility off the coast of Newport, Oregon, called PacWave, that is laying the foundation needed to move the wave energy industry forward.
“We’re interested in devices that can convert wave energy into electrical energy, and PacWave provides developers and researchers in these fields a permitted site in the ocean to deploy these types of devices,” said Burke Hales, chief scientist at PacWave and professor of oceanography at Oregon State University.
“From a developer access and cost perspective, we are providing the infrastructure to transmit the power from the ocean back to shore, condition it and put it on the local utility grid.”
The PacWave project consists of two facilities currently under construction, PacWave North and South. Each site is designed to test wave energy technologies on the open ocean, albeit in different ways.
“PacWave North is not grid-connected, it’s intended for research and development level activities for uses that are self-contained, smaller devices, scaled versions of devices that might actually be utility-scale power producers,” Hales said. “PacWave South is about twice as big, and we’re in the process right now of supplying, delivering and installing the subsea cables that will ultimately capture or allow that captured [wave] energy to be transmitted back to shore.”
Funded largely by the Department of Energy, PacWave is a collaborative research and development initiative overseen by Oregon State University, National Renewable Energy Laboratory, and a variety of other industry and government partners. Together, they hope this testing facility can support a budding wave energy industry.
PacWave is not yet operational, however, as cable installations and construction for PacWave South’s power conditioning facility aren’t projected to be completed until September 2024. But as long as the construction process continues to meet its deadlines, testing of novel wave energy technologies can begin by the end of next year.
“[PacWave] is going to have four open water test births where the global wave energy industry can come and test their wave energy systems, prepare them for deployment, either at grid-scale or at what we call ‘blue economy scale,’” said Michael Lawson, group manager of water power research and development at the National Renewable Energy Laboratory. “[PacWave] is exciting for the U.S. industry, because it’s the first time we’ve had a permanent test site [in the continental U.S.] where developers can quickly put their devices in the water, connect them to the grid and have access to data coming off the devices.”
While similar wave energy testing facilities already exist in places like Northern Europe and Hawaii, PacWave demonstrates a “first of its kind” opportunity to bring wave energy technologies to market in the Western Hemisphere.
“Nowhere in North or South America does a facility like this exist,” Hales said. “It’s the first of its kind in terms of its capacity, its power production capability, and the wave and regulatory climate that it sits in. We hope this helps get developers through what they call the ‘Valley of Death,’ which is building a great design and getting it tested at scale tank levels, but not being able to do the full-scale testing [needed] to get it commercially viable.”
Harnessing energy from waves is not easy. In order to capture and deploy this energy to the grid, one must first understand the interconnected relationship waves have with both wind and solar energy production.
“Waves have energy because they get that energy, ultimately, from wind energy [that] is driven by solar and rotation of the Earth,” Hales said. “Waves oscillate, they go back and forth. So unlike winds that are currents in fairly linear motions, we have to figure out ways to convert that oscillatory energy into another form of energy that we can transmit. The crux of this conversion is, ‘How do you go from something that goes back and forth into something that rotates?’ because [rotation] is ultimately the basis of almost every electrical generation technology that we have.”
The difficulty of converting oscillating motion into linear motion also demonstrates why other marine energy technologies, like tidal power, are more advanced than wave technologies.
“All those test methods that we’ve developed over decades for wind turbines, we can apply directly to tidal energy systems to understand what material properties these systems need to survive in the open ocean,” Lawson said. “So you can imagine tidal currents running into and out of an bay turning something like a wind turbine underwater, that’s extracting tidal energy the same way wind turbines extract energy out in the plains.”
Although harnessing energy from waves as a renewable resource for the power grid is a somewhat novel concept, that’s where Department of Energy funding, research and development opportunities can enable the nascent energy to develop.
“The wave energy industry is really starting from scratch, there’s nothing out there that really looks like a wave energy converter,” Lawson said. “There’s no commercial projects out there, yet there’s 1,000 different device concepts. In this early stage of R&D, the Department of Energy plays a critical role in getting the technologies from the drawing board to a place where commercial viability has been demonstrated at some level.”
Once wave energy technology can demonstrate its viability both in labs and in the open ocean, the benefits of it are projected to be substantial, particularly for coastal communities.
“Wave might be able to bring in something like 10 or 20% of US electricity demand,” Hales said. “That sounds like a small number. But if you can get 30 or 40% from solar and another 30 or 40% from wind. Then 20% from wave energy starts to make the portfolio whole and it’s really complementary to have this steady, relatively predictable, low-volatility asset, in the [renewable energy] portfolio.”
Lawson, too, stresses the benefits of the high-predictability and low-volatility nature wave energy offers the renewable energy industry.
“Wave is very predictable, where these other wind and solar technologies are not always as predictable,” Lawson said. “Through satellites and buoys way out in the Pacific, they can see these waves propagating towards the West Coast days in advance. If your power producers know with certainty what the waves are going to be 36 hours, 24 hours, 12 hours from now, that is something that you don’t have with wind or solar. The reliability, the predictability of these resources can increase the robustness of the grid.”
Although wave technology is early in development, researchers can speculate on how it can be deployed in collaboration with other renewables, like floating off-shore wind, to maximize its potential.
“We can perhaps have combined wind-wave farms where you’re getting more energy out of the same ocean space,” Lawson said. “You might see wave and wind being deployed together, because you already have this power cabling infrastructure that you can piggyback on to save a lot of project costs. But maybe most importantly, the wave and the wind resources are complementary in that they may be peaking at different times of day and different times of year.”
Alternatively, in coastal environments where stakeholders are concerned about visual impairments floating offshore wind farms might bring to a horizon-line, wave energy devices can also find unique practicality.
“There can be stakeholder concerns about viewscape,” Lawson said. “One nice characteristic of wave energy converters is they don’t have surface expression, or they have limited surface expression, because tidal turbines are beneath the water. So there’s some characteristics of these technologies that make them attractive in certain cases.”
Challenges in technological development and deployment remain, however, as the ocean can be a particularly harsh environment.
“We can have intense wind events, very rough seas, and these are the conditions that these devices have to survive and that resilience in the face of some really extreme conditions is critically important,” Hales said. “We have waves that might be pushing seven to nine feet off the coast because of our local summertime upwelling winds. That’s a very different sort of energy than the very long period of slow swells, which might be higher in amplitude, but is much less frequent. So is there one device that can equally and efficiently capture energy from those two very different kinds of wave fields? That’s what we need to find out with this kind of testing.”
While wave energy has its most relevant applications to coastal states and communities, there is potential for some ways in which inland and landlocked states like Nevada may indirectly benefit.
“Our electrical power system is highly distributed and the power grid extends far inland,” Hales said. “Adding power production assets, distributed throughout the grid, benefits the whole grid.”
Thanks to future operational and testing capability from a site like PacWave, wave energy may soon become an integral part of the renewable energy portfolio needed in response to climate change.
“Waves don’t set at night, they continue producing energy,” Hales said. “So it’s a highly complementary power source for the renewable portfolio.”
Editor’s Note: This story has been updated to add context and accuracy in descriptions of the process.
