CETO is a wave-energy technology that converts ocean swells into renewable power and desalinated freshwater. It was developed by Carnegie Wave Energy Limited, an Australian ASX-listed inventor and owner of the patented device. Carnegie raised over $45m to fund the development of the technology which it has tested off Fremantle, and Garden Island (HMAS Stirling), Western Australia.
CETO is designed to be a simple and robust wave technology. CETO is the only ocean-tested wave-energy technology globally that is both fully submerged and generates power and or desalinated water onshore. The CETO technology has been independently verified by Energies Nouvelles (EDF EN) and the French naval contractor DCNS.
Named after a Greek ocean goddess, Ceto, the system distinguishes itself from other traditional wave-energy devices in being a fully submerged, pumping technology that drives the hydraulic fluid onshore. Submerged buoys are moved up and down by the ocean swell, driving pumps that pressurize seawater delivered ashore by a subsea pipeline. Once onshore, the high-pressure seawater is used to drive hydro-electric turbines, generating zero-emission electricity. The high-pressure seawater can also used to supply a reverse osmosis desalination plant, creating zero-emission freshwater. Conventional seawater desalination plants are large emitters of greenhouse gases; this is due to the amount of energy required to drive the grid-connected pumps that deliver the high-pressure seawater to reverse osmosis membranes for the removal of the salt.
Traditionally, wave technologies are characterised as offshore, floating power stations.
Commercial demonstration and independent verification of results
On completion of Stage 1 of the Perth Wave Energy Project, Carnegie enlisted Frazer-Nash Consultancy Ltd to verify the CETO 3 unit's measured and modelled capacity. During the CETO 3 in-ocean trial, Frazer–Nash verified the peak measured capacity to be 78 kW and delivered a sustained pressure of 77 bar, above what is required for seawater reverse-osmosis desalination.
Perth Wave Energy Project (PWEP)
Stage 1, already been completed, involved the manufacture, deployment and testing of a single commercial-scale autonomous CETO unit off Garden Island. For this stage, the CETO unit was not connected to shore but was stand-alone and autonomous, providing telemetric data back to shore for confirmation and independent verification of the unit's performance.
Stage 2 involves the design, construction, deployment and operational performance evaluation of a grid-connected commercial-scale wave-energy demonstration project, also at Garden Island. The facility will consist of multiple submerged CETO units in an array, subsea pipeline(s) to shore, hydraulic conditioning equipment, and an onshore power generation facility.[when?]
La Réunion Wave Energy Project
The Réunion Island project is a joint venture between Carnegie and EDF Energies Nouvelles. The project will initially consist of the deployment of a single, autonomous commercial scale unit (stage 1) which will be followed by a 2MW plant (stage 2) and a further expansion of the project to a nominal 15MW installed capacity (stage 3). Stage 1 has been awarded $5M of French government funding.[when?]
Ireland Wave Energy Project
Carnegie has signed a formal funding and collaboration agreement[when?] with the Irish Government's Sustainable Energy Association (SEAI) for a €150,000 project to evaluate potential CETO wave sites in Ireland and develop a site-specific conceptual design. The project is 50% funded by the SEAI and 50% by Carnegie, and forms the first phase of detailed design for a potential 5 MW commercial demonstration project in Irish waters. The project was under way in 2011 and is being managed through Carnegie's Irish subsidiary, CETO Wave Energy Ireland Limited.
- Western Australian Government – $12.5M grant for the Perth Wave Energy Project at Garden Island.
- Australian Department of Defence & Defence Support Group – MoU for Collaboration on a CETO power and water project and offtake.
- EDF EN – Northern Hemisphere CETO Power licensee and JV development partner.
- French Government – $5M grant for Carnegie/EDF EN Stage 1 Réunion Island power project.
- DCNS – Northern HemisphereEPCM partner.
- Sustainable Energy Authority of Ireland – Collaboration agreement & concept funding for a 5 MW Irish CETO power project.
- British Columbia Government – Grant of $2M for a Canadian CETO project.
- Australian National Centre of Excellence in Desalination – Desalination research project with funding granted.
Other wave energy and CETO characteristics
- Wave energy is a renewable, high availability, zero emission source of power.
- About 60% of the human population lives within 60 kilometers of a coastline, minimising transmission issues.
- Since water is about 800 times denser than air, the energy density of waves exceeds that of wind and solar, increasing the amount of energy available for harvesting.
- Waves are predictable in advance, making it easier to predict mismatches between supply and demand.
- CETO does not stand for Cylindrical Energy Transfer Oscillating unit – a popular misconception. The name refers to CETO, a Greek sea goddess.
- CETO sits underwater, moored to the sea floor, without visual impact.
- CETO units operate in deep water, away from breaking waves. The waves regenerate once they pass the CETO units, meaning there is no impact on popular surfing sites.
- CETO units are designed to operate in harmony with the waves, rather than attempting to resist them. This means there is no need for massive steel and concrete structures to be built.
- CETO is the only wave energy technology that produces fresh water directly from wave energy by magnifying the pressure variations in ocean waves.
- Any combination of power and water can be achieved from 100% power to 100% water, combinations can be changed rapidly allowing intraday production modulation.
- CETO contains no oils, lubricants or offshore electrical components. They are built largely from existing offshore components with a predictued subsea lifespan of more than 25 years.
- CETO units act like artificial reefs, because of the way they attract marine life.
- Wave energy
- Water desalination
- Wave farm
- Reverse osmosis
- World energy resources and consumption
- Carnegie Wave Energy, 2011. Available from <http://www.carnegiewave.com/> [19 May 2011]
- Desalination, 2010. Available from <http://www.environment.gov.au/soe/2006/publications/emerging/desal/index.html> [10 May 2011]