Innovators compete in open-ocean trials using waves to turn ocean water into drinking water
Reliable access to freshwater is critical for water-scarce coastal and island communities and those hit hard by natural disasters.
That’s why the U.S. Department of Energy and its National Renewable Energy Laboratory launched the Waves to Water Prize, a competition for innovators designed to accelerate the development of small, modular, wave-energy-powered desalination systems. The event is a three-year, five-stage competition that offers up to $3.3 million in cash awards.
Beginning in 2019, 60 teams proposed, developed and designed systems that could be shipped in a standard container measuring just over a cubic meter, deployed in under 48 hours, and produce potable water from seawater.
Five devices made it to the DRINK Finale and started their first open-ocean tests at Jennette’s Pier on March 30. The in-water tests continue for five days, with related educational activities happening at the pier in Nags Head all week.
“Access to freshwater is becoming more and more critical,” said Scott Jenne, NREL’s principal investigator for the Waves to Water Prize. “This is especially true in remote locations if a natural disaster destroys access to a municipal water supply.”
During the first stage, teams took their desalination ideas from paper to prototype. They built their systems — which included wide-ranging designs like inflatable rafts, undulating seesaws, and a big, yellow, spinning top — and tested the devices’ ability to turn salt water into fresh drinking water using wave energy. Teams also strategized how to manufacture their prototypes and developed plans to transport and operate them with the agility needed for post-disaster deployment when a quick response can save lives.
Those winners each earned $100,000 to build and ship their designs to North Carolina for the final stage. The projects include:
Project 816’s Ballast, Buoys, and Borrowing from Archimedes device can be deployed in a variety of site conditions by just two people with common equipment and basic tools. The inflatable, raft-based wave energy converter—built with commercial, off-the-shelf components—powers a land-based desalination system.
Sea Potential’s DUO Wave-Powered Desalination System is an inflatable device that captures energy using a hydraulic cylinder (which uses liquid instead of air or electricity to power mechanics). The device uses that energy to pump seawater through a reverse-osmosis membrane, which extracts salt and other impurities to produce drinkable water.
MarkZero Prototypes’ rapidly deployable MZSP Freshwater Production System features pivoting arms, inflatable pontoons, an onboard, reverse-osmosis system (which turns saltwater into freshwater), and a constant-pressure, variable-moment pump, all designed to meet the changing demands of diverse ocean conditions.
Oneka Technologies’ Oneka Snowflake, the Wave-Powered Watermaker, is a circular, raft-like device that can be assembled without tools. Easy to install and adaptable to most ocean conditions, the Snowflake can produce up to 10,000 liters of clean water per week (enough for about 450 people), which is especially important for disaster and recovery situations.
WATER BROS’ Wave Actuated, Tethered, Emergency Response, Buoyant Reverse Osmosis System (WATER BROS) is a wave-powered device that has a unidirectional, rotational wave-energy conversion mechanism. Optimized for emergency response, WATER BROS is not only rapidly deployable, low cost, and highly resilient, but it also uses near-shore waves to generate clean drinking water in even the harshest conditions.
Riding the energy wave
East Carolina University’s Coastal Studies Institute has partnered with DOE to host the prize finalists at Jennette’s Pier, with experts assessing how the final designs perform in the open-ocean trials.
One winning team will earn the $500,000 grand prize for the best overall system; other teams can earn smaller prizes—adding up to a combined pool of an additional $500,000 for metrics like highest water production, cleanest water, and simplest deployment.
“Our mission,” Jenne said, “is to provide a solution that complements current technology and helps deliver clean water to communities for disaster relief purposes and to remote communities around the globe.”
Competitors in the Waves to Water Prize receive additional support from Engineering for Change, the International Desalination Association, and Janicki Industries.