Although Wave Swell Energy is a young company, having been founded in October 2016, the risks associated with the technology are low and well understood. Extensive experience in developing both the oscillating water column (OWC) and turbine has provided a vast depth of information which minimises the risks and enhances the likelihood of the success of the WSE project on King Island.
The OWC is constructed from concrete using simple molds and steel reinforcing. While the nominal life of a project is given as 25 years, this is more for accounting purposes to calculate the amortization of the unit. The OWC will actually survive for fifty or even a hundred years. Concrete caissons of a similar size and shape, used in the Normandy landing during World War II, are still in existence in the same location, with little evidence of structural wear and tear. Large concrete structures weighing thousands of tonnes (as is the case with the WSE OWC) are one of the few things that are highly resistant to the ravages of the ocean.
While the WSE turbine is not expected to exhibit the same immunity to ocean conditions as the OWC, it will readily survive the nominal device life of 25 years. Past wave energy turbines, including those developed by WSE personnel, have operated properly for many years without any unexpected issues. In addition, the WSE turbine is of a simpler design and is more robust than any previous wave energy turbine deployed in the real ocean. Standard regular maintenance of components such as bearings will ensure the turbine’s operational ability throughout its life in the ocean.
Bass Strait, 4.75 metres depth, near township of Grassy, King Island, Tasmania, Australia
The local licensing procedure involved submitting an application of intent to Crown Lands in Hobart (capital of Tasmania), requesting the location of the project on the seabed administered by that authority. This application was submitted and consent to use the ‘land’ was granted. A standard Development Application was then submitted to King Island Council and granted. All permits and approvals have now been obtained.
The King Island project officially commenced in March 2019. The UniWave200 device was installed in January 2021, with electricity commencing to the local Hydro Tasmania grid on 18 June 2021. Data from the WEC has been provided to and analysed by PNNL. The WEC is due for decommissioning in the months ahead after having reached and surpassed its official 12 month project life.
Baseline Assessment: Wave Swell Energy King Island Project
|Receptor||Study Description||Design and Methods||Results||Status|
|Fish||No studies required||N/A||Previous evidence from Oscillating Water Column projects strongly indicates fish gravitate to such structures, treating them as artificial reefs.||Completed|
|Birds, Shorebirds||No studies required as the entry to the turbine is protected by mesh||N/A||N/A||N/A|
|Physical Environment||No studies required||N/A||Unit sits on the sandy seabed under its own weight. No reefs or sea grasses present.||Completed|
|Physical Environment||Benthos – No studies required||N/A||Minimal scour predicted by independent consultants||Completed|
|Human Dimensions||Marine uses/users – |
No studies required
|N/A||The location is sparsely used. Some sailing races occur in the vicinity, although the sailing club officials are happy with the proposed location.||Completed|
Post-Installation Monitoring: Wave Swell Energy King Island Project
|Stressor||Receptor||Study Description||Design and Methods||Results||Status|
|Noise||Marine Mammals||Post-installation underwater noise monitoring for marine mammals.||It is unclear if noise from the air turbine, which is situated 8 metres above sea level, will impact mammals and penguins underwater. This study will reveal any adverse effects. Tests have measured the turbine at 74 dB at 1 metre – similar to a household vacuum cleaner. The recommendation is to monitor the underwater noise levels of the turbine at a distance of 100 metres to determine any effects on sea mammals and penguins.||N/A||Planned|