Sea waves power homes for 12 months, thanks to a blowhole wave generator
- Wave Swell spent $12 million to build its generator and tested it extensively
- It uses an oscillating column design that works like a natural blowhole
- It has an energy conversion efficiency of 48 percent, claims the company
ABC News has reported that a technology demonstrator for wave-based power generation, installed in the Bass Strait in Australia, has been powering local homes for more than 12 months.
According to the U.S. Energy Information Administration (EIA), the annual energy potential of waves off the coast of the U.S. is 2.64 trillion kilowatt-hours, roughly 66 percent of the country's annual power generation. Abundantly available throughout the year, sea waves can be a valuable addition to the growing list of renewable sources of energy that we are tapping into to reduce our dependence on fossil fuels.
However, there is a significant problem. Scientists have not been able to arrive at an optimal design to harness energy from the waves. While some have attempted to use bobbing buoys, others have tried to tap into the pressure differences on the sea floor as the waves pass overhead to generate power, all to not-so-acceptable results.
Wave Swell: Where others have failed
Wave Swell's first energy generator unit is different because it has a blow hole design. Named the Uni Wave200 generator, with a whopping cost of 12 million dollars, it has been extensively tested at the Australian Maritime College, according to the ABC News report.
Although the generator is designed to be used in the seas, it has no moving parts inside the water. Instead, it uses an oscillating water column design that mimics a blow hole. The entire structure sits on the sea bed, and an opening on one side allows waves to move in and out of the chamber. Waves enter the column, and as they rise and fall, they push air into the turbine located on the top of the generator assembly, which then moves to generate power.
The Uni Wave 200 can generate 200kW at its peak, which is enough to power 200 homes. Last year, we reported that the generator was to be connected on a trial basis in the Bass Strait, and it has now been running for over 12 months.
How has the trial turned out?
Speaking to ABC News, Wave Swell CEO Paul Geason said that the generator had achieved conversion rates of 48 percent. This means that out of the total energy brought in by waves, the generator supplied 48 percent of that to the grid. "That rate is very encouraging and, in fact, is higher than other renewable energy technologies," Geason added.
With the unit operating for over 12 months, the company is ready to look at the next step in commercializing its technology. The next iteration of their wave generator is expected to generate five times as much energy as the UniWave 200 and could be placed on any coastline worldwide.
The wave generators could also be part of the breakwater or sea walls that nations are preparing to build as the sea levels rise and coasts erode. After a successful demo, interest in the technology has come from different world regions.
However, there is also the stigma of other projects in this domain. "In our industry, people remember the ones that didn't work and think, 'Oh well, that's ocean energy, so it can't possibly be successful,' when in fact, that's not true, and this unit [UniWave 200] has proven that," Geason told ABC News.