The power of the ocean’s waves, currents and tides is immense. Step into a strong current at the beach or dive under a wave breaking on your head and this is easily discovered. The challenge for those working to turn such a wild source of renewable power into energy is first to capture it and then ensure it can be delivered and used efficiently as electricity.

While ocean power is still in the early stages of development in Australia, the past decade has seen the successful development of some major projects around the country and increasing government support. Oceanlinx, BioPower and Carnegie Corporation have emerged as the major players in the ocean power field.

Oceanlinx wave power

International company Oceanlinx has the most advanced wave power technology in Australia, with a commissioned power station in New South Wales and plans to develop the largest wave energy project in the world in Portland, Victoria.

Dr Tom Denniss founded the company, then Energetech Australia, in 1997 to develop a unique oscillating water column device (OWC) and a turbine that would more efficiently fuel a generator.

Now completely developed, the Oceanlinx OWC chamber narrows so that the air passing through it is accelerated to its highest velocity as it passes the turbine. Unlike most turbines, which are designed to function for a gas or liquid flowing in one direction, the blades of the Denniss-Auld turbine oscillate with the airflow through the chamber and the turbine converts energy on both the up and down stroke.

In October 2005 the company was the first in the world to successfully generate power from a floating water column at its test site in Port Kembla, New South Wales. By December 2006, Energetech’s Wave Energy Generator was successfully installed off Port Kembla, transforming energy from waves into electricity or desalinated water.

In October 2007 the company announced six project developments and contracts, totalling circa 73 megawatts (MW) in aggregate capacity. This included the advanced permitting stage for the waver energy project in Portland, for 18 units totalling 27 MW of power and a Power Purchase Agreement with Integral Energy for the supply of electricity from the prototype 450 kW unit based at Port Kembla. This will be the first offshore wave energy company to be connected to the commercial grid. Overseas, Oceanlinx is developing projects in the United Kingdom, the USA’s Rhode Island State Authority South Africa and Hawaii.

BioPower Systems wave and tidal power

In January BioPower Systems received an investment of $1 million from the Australian Government’s Renewable Energy Equity Fund, CVC REEF, to develop designs for full-scale prototypes of its wave and tidal-current energy converters.

The company’s ocean power conversion technologies are based on the concept of biomimicry, using biological species as inspiration in engineering design. The bioWAVE wave power system and bioSTREAM tidal power systems both derive beneficial traits from certain sea plants and swimming species.

“By observing the way plants and fish interact with the ocean environment, we have been able to borrow some aspects and integrate these into our designs to improve efficiency and survivability,” said BioPower’s Chief Executive Officer, Dr Tim Finnigan.

The investment by CVC REEF is a follow-up to an earlier CVC REEF seed investment that provided funding to support model-scale prototype tank testing at the Australian Maritime College in Tasmania. Dr Finnigan said the earlier investment had allowed the company to verify the technologies, with very promising results.

BioPower is currently in the process of securing further funds to develop a project that will involve ocean deployment of full-scale prototypes.

Carnegie Corporation wave power

Carnegie Corporation is the third Australian company making major waves in Australia’s ocean power industry. In early 2008 the company successfully deployed two CETO 2 Wave Energy prototypes off the CETO test site at Fremantle in Western Australia.

Named after the Greek ocean goddess, the CETO technology distinguishes itself from other wave energy devices by resting out of sight on the ocean floor. An array of submerged buoys is tethered to seabed pump units. The buoys move in harmony with the motion of the passing waves, driving the pumps which in turn pressurise seawater and deliver it ashore via a pipeline. The high-pressure seawater can be used to supply a reverse osmosis desalination plant, replacing greenhouse gas emitting pumps usually required for such plants. The high pressure seawater can also be used to drive hydro turbines and to generate zero-emission electricity.

The manufacture and pre-deployment testing of the first CETO 2 unit took place in Perth in late 2007. Deployment was then carried out in January onto pre-deployed moorings. High pressure piping was connected as part of the process and water is now being delivered back to the onshore Fremantle facility.

The company is aiming to have its CETO technology commercially ready by 2009. Two units will be deployed offshore at Fremantle throughout 2008, creating a mini CETO wave farm. This will be followed by the deployment of a full-scale CETO 3 unit at a deepwater test site, which will complete the CETO development program in 2009.

Ocean power and Australia’s future energy mix

South Australia University Senior Research Fellow Brian Birke says ocean power technologies are important for Australia’s future renewable energy mix.

“A combination of renewables offers more total power and less variability than relying on any one. Hence wave and tidal complement wind, geothermal and hydro,” he explains.

However he notes that the industry faces some major challenges in developing the technology.

“Australia is physically isolated from the ‘epicentre’ of [ocean power] activity in United Kingdom, Europe and North America, so locally manufactured hardware must be transported long distances to those markets,” he says. “Australia also has a relatively small economy without the resources to do everything on a grand scale like the United States.”

Finally, he says that Australia seems to suffer from an environment where it is very hard to get financial support for new technologies. Nonetheless, he remains positive about the future and the large potential markets for Australian innovations in Asia.

“We have a culture of innovation and we must be prepared to back our home grown products,” says Mr Birke.