Competition challenges inventors to use wave energy to desalinate seawater

The struggle to build what could be the next big thing in renewable energy began in a garage in Colorado. The designers collected about $100 worth of rubber, pipes and valves for wave energy experiments.

They used these materials to build a small air pump in 2017. Then they tied it to the bottom of a shallow body of water so that it could float under the water. The pressure generated by the waves moving above it will instantly push the flexible diaphragm of the pump.

The compressed air in the pump pushes the water into the pipe. As the elastic diaphragm returns to its old shape-ready for the next wave-a one-way valve system keeps the water in the tube moving.

“I have been tinkering,” explained Dale Jenne, a mechanical engineer at the National Renewable Energy Laboratory. As a teenager, he began to use lightweight, flexible materials by repairing the fiberglass body of the early Chevrolet Corvette.

Years later, when Jenne was asked to assist other NREL researchers in researching new versions of old ideas, his work on sports cars came to mind. Jenne explained in an interview that they are trying to “transform a lot of energy in the waves into some meaningful form or work.”

Many companies have tried, but their projects to extract wave energy—some costing millions of dollars—mostly ended in failure. By 2015, the use of solar and wind energy has become a big business, but the use of wave energy is still a dream.

Most of the early equipment was made of steel. They are usually like tanks, designed to withstand the impact and corrosion of waves. So the idea that you can extract wave energy with lightweight, inexpensive materials is radical.

As a result, Jenne and his other inventor, Yi-Hsiang Yu, another NREL researcher, decided to build the first version with their own money in Jenne’s garage.

“This is not just a completely crazy idea. We want to understand the right way,” Jenne explained.

The pump is working. The idea of obtaining energy from lightweight wave-powered equipment has developed into one of the major competitions of the Department of Energy.

It is called “Waves to Water” and its goal is to use enough wave energy to desalinate seawater.

The competition was launched in 2019 with a prize of 3.3 million US dollars and requires a five-stage competition to develop the best wave energy equipment. The rules require the winner to provide a machine that can “survive in harsh sea conditions,” which can be loaded into a standard container and deployed within 48 hours of coastal disasters such as hurricanes that shut down the power system.

Is this a crazy idea?

Victims of New Orleans’ massive power outage following Hurricane Ida and the ensuing drinking water shortage may not think so. 65 teams from companies and universities around the world also did not participate in the NREL competition. They include some inventors who have been working on small wave energy devices since 2012.

So far, they have competed in four stages: propose a wave power system, develop a detailed plan and model, find a test method, and then prove its function. Soon, NREL will choose from four to six finalists in these early stages to build their system and participate in the competition.It will use Jennette’s Pier, a fishing pier that extends 1,000 feet into the Atlantic Ocean in Nags Head, North Carolina

The last stage is called “drinking”. The judges will measure how much water is transported and the amount of salt removed from it by wave energy. According to Jenne, the championship will receive a cash prize of at least $500,000 and may also be eligible to win other awards.

Contestant

In the early stages of the competition, participants studied their competitors’ systems. Some teams even merge to produce winners.

Jenne explained that focusing on smaller wave energy systems “is expected to provide a faster track for innovation before we jump into larger systems.” He hopes this will prove that wave energy is ultimately at a “critical point” and is ready Used for more ambitious purposes.

The finalists for “Drink” have not yet been announced, but Jenne said their approach is different. Some people use waves to generate electricity to desalinate seawater. Others switched directly from mechanical power driven by waves to reverse osmosis, a process that uses a pump to force seawater through a semi-permeable membrane. This removes at least 95% of dissolved salts.

One of the earlier winners was a Canadian company called Oneka Technologies Inc., which spent six years designing modular buoys of different sizes for desalination. It has received funding from investors in Canada and the United States and Europe. It has commercial projects in Florida and Chile.

Another early winner, California company CalWave Power Technologies Inc., developed the so-called “HydroNode.” It is a light inflatable buoy that can be deployed from a small boat. When the waves shake the equipment, the motion generates energy to power the land-based reverse osmosis system.

“Team Canvasback” is the merger of Irish company Wave Venture and Jack’s Plastic Welding in New Mexico. Part of its design comes from Jack’s inflatable life raft for American astronauts who landed on Earth. Ocean.

Another Irish contestant, Sea Power Ltd., uses the movement between two wave-driven floating pontoons to develop electricity for desalination. According to Sea Power, the process has been tested since 2012 and survived waves of more than 10 feet.

NREL’s partner in handling the upcoming tests will be the North Carolina Renewable Ocean Energy Program, which is run by George Bonner, a former U.S. Coast Guard commander and civil engineer.

“We are excited about the’drinking’ phase,” Bonner explained, who will lead a team to help contestants deploy their equipment safely from the dock.

The Bund in North Carolina is already familiar with reverse osmosis. More and more salt water invaded the well water in the area, leading to the construction of four desalination plants powered by the grid.

Jennette’s Pier is the site of the final test. It usually attracts 250,000 visitors each year, mainly for fishing, but Bonner points out that it already has three wind turbines running on it.

He believes that the final stage of joining “Waves to Water” will “make it a “great platform for educating people about renewable energy.”