ENERGY SECURITYHow Much Wave Energy Is in Our Oceans?
The ocean is never still, but exactly how much energy surges through our ocean waves is a matter of debate. That uncertainty makes it challenging for countries to weave wave energy into their future climate goals. New study could help countries better estimate how much power their waters carry.
The ocean, like a teething toddler, is never still. And both creatures contain shocking amounts of energy. But exactly how much energy surges through our ocean waves is a matter of debate. That uncertainty makes it challenging for countries to weave wave energy into their future climate goals: How can you rely on something you cannot accurately measure?
Now, in a recent study published in Renewable Energy, researchers from the National Renewable Energy Laboratory (NREL) and Pacific Northwest National Laboratory present a more comprehensive and accurate methodology to measure the wave energy available in ocean sites around the world. But they also identified another challenge: Existing wave energy data sets, the ones the team used to build their new methodology, may not be as reliable as previously thought.
Wave energy is not only predictable—making it a valuable complement to variable renewable energy sources—it is also available along coastlines where the majority of the world’s population lives. But wave energy could do more than power coastal communities; this renewable could create clean drinking water from the ocean, power offshore seafood farms, and help decarbonize international shipping—all with energy from the ocean itself.
But to plan for all those applications—each of which will require investments from companies, industries, or entire countries—we need reliable data.
“Wave energy technology is at such an early stage,” said Levi Kilcher, a senior researcher at NREL and the lead author of the study. “Because the industry is still young, it’s challenging to estimate how much energy future technologies might capture.”
For this study, which was funded by the U.S. Department of Energy’s Water Power Technologies Office, the team built a new method to estimate total wave energy potential. “The original wave resource assessment was a great first start. But there were also several critiques of that method,” Kilcher said.
For example, previous methodologies did not account for wave direction—which direction a wave rolls in from. “That can actually lead to double-counting waves,” Kilcher said.
Some waves are born far offshore, frothed up by a storm perhaps, and travel thousands of miles before crashing on a country’s shoreline. “But there’s quite a bit of wave energy that’s generated by winds blowing inside a country’s maritime boundaries,” Kilcher said. His new method accounts for wave direction and those local waves, too.
“The other neat thing is that our method works for all scales—from the very small, single-project scale all the way to the entire ocean basin,” Kilcher added.
