An incredible sea platform built by Wave Swell Energy called UniWave 200 uses a manufactured blowhole formation to shift air pressure, powers a turbine, and sends energy back to land. The company says the testing has produced outstanding results after only a year.

The floating UniWave system can be towed to any coastal area and connected to the regional power grid. It is built to pressurize the air in the chamber and force it through an outlet valve as a reaction to wave swells pushing water into a specially constructed concrete chamber. After that, when the water recedes, a strong vacuum is created. This powerful vacuum draws air into a compact turbine at the top, which turns a generator to produce electricity that is then conveyed to the energy grid via a cable.

The team claims that because it harvests energy from the whole water column that enters its chamber, it is more effective than wave energy generators that only collect tidal power from the top of the ocean floor.

The main advancement made by WSE, in this case, is the one-way generation; other devices that achieve the same result use bi-directional turbines, requiring the ability to modify the airflow direction or the blade pitch. According to WSE, this blow hole design enables considerably less complex and expensive turbines that should survive longer because they don’t get as much salt water blasting through them when a large wave strikes. In addition, the fact that this device’s moving parts are all above the waterline should help to increase its service life and ensure that it is entirely safe for marine life.

The UniWave’s modular design makes it ideal for installation in seawalls and breakwaters, transforming coastal erosion control initiatives into renewable energy generators. The following video provides an animation illustrating the process.

Last year, a 200-kW test platform was installed off King Island, in the notoriously choppy waters of the Bass Strait, which divides the island state of Tasmania from the Australian mainland. There, it has continuously provided dependable, clean energy to the island’s microgrid for an entire year. In addition, the WSE team made several real-time design refinements while it was in use, significantly increasing its performance.

Paul Geason, the CEO of WSE, said in a press release:

“We set out to prove that Wave Swell’s wave energy converter technology could supply electricity to a grid in a range of wave conditions, and we have done that. One key achievement has been to deliver real-world results in Tasmanian ocean conditions to complement the AMC test modeling. In some instances, the performance of our technology in the ocean has exceeded expectations due to the lessons we’ve learned through the project, technological improvements and the refinements we have made over the year.”

According to Geason, the WSE team converted wave power to electricity at an average rate of 45 to 50% under various wave circumstances. “The conversion rates that we’ve been able to achieve in terms of the amount of electricity we are able to extract from the wave energy that comes into the unit is very high. This is a vast improvement on past devices and shows that the moment has arrived for wave power to sit alongside wind, solar and energy storage as part of a modern energy mix,” he added.

Geason commented on the device’s energy output during the trial:

“It’s important to stress that the demonstration at King Island was not about producing high volumes of electricity. Rather, it was to prove our technology’s capabilities in various wave conditions. The results have met and, at times, exceeded our expectations. For example, when the unit generates 40 kW of power in reasonable wave conditions, you could extrapolate the amount of energy to be in the order of 1MWh in a 24-hour period.”

The King Island project is expected to stay in operation through the end of 2022, and preparations for production are already underway.

“Having proven our device can survive the toughest conditions the Southern Ocean and the Bass Strait can throw at it and deliver grid-compliant electricity, our priority now shifts to commercializing the technology. For Wave Swell, this means ensuring the market embraces the WSE technology and units are deployed to deliver utility-scale clean electricity to mainland grids worldwide.”

Furthermore, Geason mentions the possibility of size variations in commercial deployments. “The units can scale up from 200 kW. But, of course, the exact size will depend upon the attributes of the wave climate at any particular location. We’re currently engaged with several third parties seeking to deploy commercial units, and our efforts and resources are focused on further deployments and commercialization of our technology.”

Another remarkable floating wave energy device is Sea Wave Energy Ltd’s Waveline Magnet. After many generations of onshore and offshore prototype testing, the company asserts that it offers the “cheapest clean energy ever.” However, Unlike WSE’s concrete-based blowhole energy generator, it can be constructed entirely from recycled materials.

Watch the video below to see the UniWave 200 test platform in action.