A team of students mentored by Lei Zuo, the Robert E. Hord, Jr. Professor in mechanical engineering, is sailing into the third stage of a national competition backed by U.S. Department of Energy (DOE).

The Waves to Water Prize is a five-stage, $3.3-million contest to accelerate the development of small, modular, wave-powered desalination systems capable of providing potable drinking water in disaster-relief scenarios and remote coastal locations. This is the first prize administered as part of the U.S. Department of Energy’s Water Security Grand Challenge.

Access to clean, sustainable drinking water is a matter of concern around the globe. According to the World Health Organization, 785 million people worldwide lack this access, and half the world’s population is predicted to be living in water-stressed areas by 2025. The irony is that water covers 71 percent of the earth’s surface, with 96 percent of all water on the planet forming the oceans. To make that water drinkable, it must be desalinated, or de-salted.

Desalination takes on multiple forms, but usually is achieved by either reverse osmosis (pushing the salty water through a partially permeable membrane) or distillation (phase separation methods such as boiling). The DOE report “Powering the Blue Economy” identifies wave-powered desalination as a potential growth market for marine energy technologies, particularly targeting isolated coastal/island communities with high energy costs. Wave energy-powered desalination systems could help address coastal challenges, such as resilience, disaster recovery, and water scarcity, especially if systems are competitive on price, water production, and reliability when compared to conventional alternatives.

Students led by Ph.D. student Jia Mi from Zuo’s Center for Energy Harvesting Materials and Systems have blended their expertise in marine renewable energy with the expertise of a group of students in desalination led by Vanderbilt University Professor Shihong Lin. The joint team is known as Wave Drinker, and they have already advanced through both the concept and design sections of the competition. Seventeen teams were selected to proceed past the second round, with each receiving an even split from $800,000 to produce working prototypes of their systems. Wave Drinker’s portion, more than $47,000 in, is enabling them to create and assemble their system. They are one of only four teams left in the race to be led by academic institutions.

The current objective of the group is to develop a wave-powered desalination system which can produce at least 400 liters of fresh water within five days, the requirement of this third competition round. The contest rules come with a few constraints. The team must build a system than can be set up in under 48 hours, the total system weight cannot exceed 650 kilograms, and the system must be shipped in a container no larger than 41 by 44 by 35 inches. According to team captain Jia Mi, Wave Drinker’s solution can meet the requirements, and their modeling predicts water production much higher than the minimum requirement.

Up to 10 winners will be chosen to advance to the fourth round, where they would split a $500,000 prize evenly to further improve their design and compete for a final stage.

The Virginia Tech Wave Drinker team members include Ph.D. candidate and captain Jia Mi, master’s student Joseph Capper, post-doc Qiaofeng Li, Ph.D. candidate Xiaofan Li, and undergraduate students Ziming Fang and Yizhi Wang.

Written by Alex Parrish