The Perth Wave Power Project (PWEP) is an innovative offshore development in Garden Island, Western Australia (WA). It was developed by Carnegie Wave Energy and officially switched-on in February 2015.
The plant has a peak rated capacity of 5MW and can produce desalinated water. Carnegie signed a power offtake agreement for the project with Synergy. The electricity generated by the project is sufficient to power approximately 3,500 households.
Carnegie claims it to be the most advanced wave power project in Australia. PWEP is also the first commercial demonstration project of Carnegie.
The project created 30 jobs and won the Sustainable Energy Industry Excellence and Innovation Developer Award from the WA Sustainable Energy Association in March 2010.
The project secured environmental and safety approvals in December 2012 following a two-year environmental impact assessment. It received planning approval from the WA Government in February 2013.
Detailed design was completed in 2013 and construction was started in September 2013. The project has recorded more than 14,000 cumulative hours of operation
Perth Wave project details
The Perth Wave Power Project uses Carnegie Wave Energy’s innovative, proprietary wave energy technology called CETO.
The project is located offshore of Fremantle at a 25m water depth in the ocean between Garden Island and Five Fathom Bank. It is situated 3km offshore from HMAS Stirling, Australia’s largest naval base. It is also located close to the National Centre of Excellence in Desalination (NCED), Rockingham.
Make-up of Western Australia wave energy plant
The offshore wave energy project is mainly made up of three CETO units in water, high-pressure subsea pipelines to transfer the pressurised water onshore and a power generation system onshore.
The offshore structures are supported by pile foundations. The onshore generation system, completed in January 2015, is connected to the power grid at HMS Stirling.
Financing of Australian wave energy development
The project was completed at a cost of $39.87m. Carnegie received a $13.1m grant for the project from the Australian Federal Government under the emerging renewables programme (ERP). Another $10m was provided by the Western Australian Government under the low-emissions energy development (LEED) programme.
The company also secured $13.09m in funding from the Australian Renewable Energy Agency (ARENA) and a private equity funding of $16.2m from the Australian Special Opportunity Fund managed by Lind Partners.
An additional $5.8m was secured in the form of private funding ($3.525m) and government grants ($2.26m) in November 2012.
The desalination plant was partly funded through a $1.27 AusIndustry grant under the Clean Technology Innovation programme.
The company also received a $200,000 payment from ARENA for the CETO 6 in 2017.
Development of the Western Australian power project
The Perth project was officially launched in January 2010 at Carnegie’s Wave Energy Research Facility in Fremantle. It was delivered in two stages. The first stage, with 2MW peak capacity, was launched in 2010 and completed in April 2011. The second stage has a capacity of 3MW at peak.
Performance evaluation of the Perth commercial demonstration project will help Carnegie to develop similar commercial scale projects and start earning revenues from this innovative renewable energy technology.
Since the project is near to the HMAS Stirling Naval Base, Carnegie entered into a memorandum of understanding (MOU) with the Department of Defence in January 2009 for the development and offtake of power and water for the project.
The CETO 5th generation units were installed in 2015. A wave energy (hydraulic) powered desalination system was also connected and operated to produce power for the Department of Defence.
The project was partly decommissioned to deploy a larger capacity CETO 6 pre-commercial array to connect back to Garden Island. The CETO 6 deployment project was completed at a cost of $33m in October 2019. The CETO 6 can offer up to 1.5MW output per unit and incorporates the power generation offshore, inside the buoy.
The new design facilitates simplified installation and maintenance programme by eliminating the necessity of heavy offshore lifts and associated costly heavy lift vessels.
Contractors involved with the PWEP project
An MOU was signed with Hatch Engineering for the engineering, procurement, construction, and management of the project.
The contract for the design of the turbine and generation system was awarded to Tyco Tamar. Two consultancies, namely RPS Consulting Engineers and Geomarine, were awarded the contract for the foundation design. The pipeline design contract was awarded to INTECSEA, a WorleyParsons Group company. Flexsteel Pipeline Technologies supplied the pipe, while Total AMS (TAMS) installed the same.
Keppel Prince Engineering (Keppel) provided structural pile foundations and fabrication works for the project.
CETO unit attachment and foundation and CETO tether were provided by Subsea Riser Products (SRP).
ABB Australia supplied an Onshore Plant and Process Control System under a contract awarded in September 2013.
Construction of Perth Wave Energy Project
Construction of stage one of the projects began in 2010 and it has been operating successfully since April 2011. The jack-up rig for drilling the pile foundation for stage one was supplied by Boskalis Australia. Stage one was initially not connected to the grid. It was only operated as a stand-alone system for about 12 months for testing.
As part of stage one of the project, a commercial scale CETO unit was deployed in the Sepia Depression in 2010. The Sepia Depression is located between Garden Island and Five Fathom Bank.
The deployed system consisted of the mooring and a CETO unit. A telemetry instrumentation buoy was also installed to send data back to shore for confirmation and independent verification of the unit’s performance.
The desalination plant was constructed by MAK Industrial Water Solutions and was supported by a $1.27m grant from Australia’s Clean Technology Innovation Program.
Technology used at Carnegie Wave Energy’s plant
The CETO power system is anchored to the ocean floor and operates out of sight. The technology involves tying up of an array of submerged buoys to seabed pump units.
The passing oceanic waves cause the buoys to move harmonically. The pumps are driven by the moving buoys, causing the water pressure to increase. The high-pressure water is carried to shore via a pipeline.
The pressurised water can be used to drive hydroelectric turbines to generate electricity. The entire process consumes zero electricity and causes zero emissions. The water can also be used to drive the pumps of a reverse osmosis plant for desalination, eliminating the consumption of electricity by the pumps.
The plants using CETO technology has the least visual impact as most of the plant infrastructure and equipment is submerged.
In September 2012, Carnegie unveiled the design for a new CETO 5 unit used in the project. The new design incorporates significant improvements over the previous generation CETO units including CETO 3 and 4. The CETO 5 unit has a higher diameter of 11m compared with the 7m diameter of the CETO 3 unit. It has a rated capacity of around 240kW, which is three times higher than that of CETO 3.
The project is expected to reduce greenhouse gas emissions of more than 500,000t over its entire life. A unique feature of the CETO technology is that it is fully submerged underwater and attracts marine life.