This yellow floatie can churn the power of the sea into electricity

One day, ships and buoys could get their energy from the waters themselves.
ocean wave crashing
The ocean contains an immense amount of unharnessed power. Pixabay

In just a few short days, researchers will float a yellow platform out into the waters of the Pacific Ocean, north of the Hawai’ian isle of O’ahu. It’s not just there to roll upon the waves. It’s called SeaRAY, and if all goes well, it’ll turn those very waves into electricity.

The platform is the latest example of wave power. Despite a name that might sound like an energy drink, it’s a very real, very green power source. Researchers across the globe are trying to harness the energy of ocean waves—energy that would otherwise go into eroding beaches, rocking boats, and destroying sandcastles—and turn it into electricity.

“You know if you’ve walked along the beach on a stormy day,” says Bryson Robertson, a professor of civil and construction engineering at Oregon State University. “There’s a lot of destructive energy, and possibly constructive energy, that we can harness and put to use.”

There’s multiple ways and multiple technologies that make this possible. “There are many different designs out there,” says Rebecca Fao, a researcher at the National Renewable Energy Laboratory (NREL) in Boulder, Colorado, who works on SeaRAY. “Each developer has their own methodology for extracting energy from the waves.”

Wave energy could, for instance, charge up the buoys that landmark the sea. It could power the desalination plants that make seawater drinkable, potentially providing life-sustaining hydration to places like islands that need it most. It could help make aquaculture more sustainable. And it could power electric vehicles at sea.

researchers standing in front of SeaRAY
NREL teammembers standing in front of SeaRAY. NREL/C-Power

It’s that last application which is, currently, of the most direct interest to Fao and her colleagues at NREL. In cooperation with Columbia Power, they’re working to build a wave energy converter that can power what is, effectively, an underwater version of an electric vehicle charging station. It’s a station where undersea drones—fulfilling missions like studying ocean life and mapping the seafloor—could stop to recharge.

NREL, in particular, is working on the data side of the project, creating a system called Modular Ocean Data Acquisition (MODAQ). It’s a data collection system that will continuously measure the waves, the currents, the winds, and how the platform moves in the face of all those. MODAQ will allow the scientists behind SeaRAY to understand if the platform works as intended.

“We’re really hoping to also be able to demonstrate our controller capabilities,” says Fao. “So, really, showing that this MODAQ system can be the brains of these wave energy devices.”

There are good reasons for that. For one, putting something out to sea carries inherent logistic challenges. “You need a boat to get out there, whereas a wind turbine or solar power, you can just sort of wander over,” says Robertson. And, in time, the water itself can turn against you—seawater is very corrosive. Over SeaRAY’s six-month-long test, he says, that’s something its creators will need to carefully monitor.

It’s worth it to tap into the power of the waves. Researchers calculate that Earth’s oceans hold more than two terawatts of wave power, equivalent to several thousand nuclear power plants. If there’s a way to turn all that into usable electricity, it could make quite the dent in carbon emissions. Waves, to wit, are always lapping—unlike solar and wind, which aren’t so reliable when the sun hides or when the weather is calm.

[Related: Renewable energy needs storage. These 3 solutions can help.]

But there’s not yet an equivalent to the sprawling solar farms or massive offshore wind developments that are so prevalent in the world of renewable energy. It’s not that wave power is a new idea; patents for wave power have been around for well over a century, and there was a flurry of interest in it during the energy crisis of the 1970s. 

Large-scale wave power has simply never taken off. The logistical challenges have been too great, and no one’s yet found the technology that will allow us to build functioning wave power plants.

So, perhaps it isn’t practical to think so big, at least not yet. Researchers agree: most of the focus at the moment is on individual applications, such as SeaRAY. 

But that doesn’t mean that SeaRAY can’t evolve into something bigger, like a snowball rolling downhill. “If you look at solar, they started with powering calculators,” says Robertson. “We all had one of those calculators in the 80s and 90s that had a tiny little solar panel.”

And for now, the researchers hope that SeaRAY paves the way for all the things we do in the ocean to, in essence, draw their power from the ocean itself.