Description
The Wave Swell Energy (WSE) King Island project involved the design, construction, deployment, operation, and decommissioning of a 200kW version of the company’s technology – the UniWave200 – in open ocean waters off Grassy Harbour on the south-eastern coast of King Island in Bass Strait.
The unit was installed on January 10, 2021, exporting its first power into the King Island grid on June 18, 2021. It was decommissioned in late 2022 and was removed from site on 28 Mar 2023.
WSE worked with Hydro Tasmania, the island’s energy and network provider, to connect the unit to the local grid, and delivered energy from the project into the existing network. Hydro Tasmania separately monitored the energy produced by the unit to ensure it met the requirements of the King Island grid.
The wave energy produced complemented Hydro Tasmania’s existing hybrid grid, further diversifying the renewable sources and reducing diesel consumption on King Island.
Location
Bass Strait, 4.75 metres depth, near township of Grassy, King Island, Tasmania, Australia
Licensing Information
The local licensing procedure involved submitting an application of intent to Crown Lands in Hobart (state 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 were obtained.
Project Progress
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 was decommissioned and removed in late March 2023, having reached and surpassed its official 12-month project life.
Key Environmental Issues
None encountered.
(No official project environmental web page. Company web site is www.waveswell.com).
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. | A noise monitoring program based on recommended practice referenced in the EPA document Noise Measurement Procedures Manual 2008. Noise levels were measured as not exceeding 64.3dB at 50 metres distance, which occurred when the turbine was operating at its maximum rotational speed of 2000 RPM. More typical turbine speeds resulted in noise levels of less than 60dB. | An assessment by Marine Solutions Tasmania Pty Ltd concluded the project is not considered to pose a threat to marine mammals. Furthermore, the same assessment concluded “Anthropogenic noise is considered ‘of less concern’ for Little penguins. Little penguins swimming past the unit could utilise avoidance behaviour, and it is unlikely that noise will be heard at levels warranting concern from individuals on the shore. | Completed |