In Colorado, where the Rocky Mountains meet the high plains, researchers have been working on a problem that affects millions of people around the world: how to turn the endless motion of ocean waves into something useful — fresh drinking water.
The team at the National Laboratory of the Rockies (NLR) has been improving a device called HERO WEC since 2020. HERO stands for hydraulic and electric reverse osmosis wave energy converter — a mouthful that basically means a machine that uses wave power to remove salt from seawater. The project is funded by the U.S. Department of Energy's Hydropower and Hydrokinetic Office.
Researchers began with version one of their device, testing it hundreds of hours across three lab programs and five real ocean deployments. After learning from those experiences, they moved on to building version two. One of their biggest breakthroughs? A custom-built charge controller — the part that manages electricity flowing from the wave converter to batteries.
"The original V1 charge controller used off-the-shelf components designed for other variable energy technologies," the team explained. But here's the catch: waves don't behave like wind or sunlight. They surge and stall unpredictably, and standard parts couldn't keep up.
So the researchers built something new from scratch. They sketched their idea, used computer design software to refine it, and then constructed the physical component. The device — roughly the size of a large ice chest — was tested first on a lab bench, then connected to a simulated ocean environment with a generator and fake battery system.
The results surprised even the engineers. The new charge controller captures up to eight times more power than the original design. That means the wave converter can charge batteries more reliably, run the reverse osmosis system consistently, and ultimately produce more fresh water from the sea.
But the team didn't stop at solving their own problem. They designed the controller to be flexible and adaptable — a blueprint that other wave energy developers can customize for their own devices. Both the hardware and software can be modified to fit different wave converters' power needs.
Now, NLR's wave-powered desalination team is opening the door for collaboration. They're inviting technology developers to integrate this proven design into their own systems, potentially accelerating wave energy projects around the world.
It's a small box packed with big ideas — and it might just help bring clean water to coastal communities that need it most.