Monday 11 September 2006

Converters test the ocean's might

Weekend Australian
Saturday 9/9/2006, Page: 6

The sea has the potential to meet more than 10 per cent of the world's power needs, writes Keith Orchison

ANYONE who has been dumped while surfing knows how much energy there is in the sea, and an Australian company is among a number around the world now pursuing the use of ocean waves to generate emissions-free electricity in competition with solar, geothermal and wind resources.

Sydney-based Energetech Australia is in the forefront of international effort pursuing the deployment of a large-scale commercial wave energy converter, with its technology described by the prestigious Electric Power Research Institute (EPRI) in California as one of the few devices in ocean energy development that has overcome most of its technical challenges.

Tapping the thermal energy of the ocean has been a dream for researchers for more than 200 years, with the first experimental system installed in Cuba in 1930, but the concept has been continuously over-run by fossil-fuelled power for decades and more recently by the advances of wind power.

Today increasing demand for energy around the world, strong rises in fossil fuel costs and the growing urgency of the search to abate greenhouse gas emissions are driving the interest in wave and tidal power as well as other forms of renewable energy. The first wave power production was delivered to an electric grid in Scotland in 2004.

However, the technology faces the risk of cruel seas - storms have wrecked pioneering wave power plants offshore Norway and Britain and damaged another off the Azores islands.

The Energetech plant is one of a number of small-scale commercial ventures being pursued across the globe and the company has just completed its third ocean trial off 'Port Kembla harbour at Wollongong. The company is also investigating development of a $40 million plant at Portland, Victoria, which would generate enough electricity for 30,000 homes or desalinate enough water for more than 50,000 houses.

The company has attracted venture capital of more than $20 million from Australia, the US and Europe and has grant funding from the federal and Victorian governments exceeding $3.3 million.

Energetech's chief financial officer, John Bell, has told media in western Victoria that Portland would be a good site because it has one of the best "wave climates" in Australia.

He explains that the technology works best with waves of between one and three metres, which are forced into a chamber by V-shaped arms, producing a vertical movement of air to drive a turbine powering a generator. The device is suitable for deepwater coastal locations such as harbour breakwaters and rocky headlands and cliffs. It can be deployed as a single unit or strung together in a series, similar in concept to wind farms. It can also be integrated in to the structure of harbour breakwaters.

If the Portland development goes ahead, it will consist of 10 to 15 wave energy units installed one to five kilometres from the shore. Each unit is 20m in length and width.

Energetech is also pursuing potential developments in Canada, the US and Europe.

One of its main competitors in the worldwide race to establish a wave power industry is the Irish company Finavera Renewables, which has recently been awarded $A5 million by the European Commission to install a demonstration plant off the coast of Portugal as the first step in laying out a 100 megawatt system, large enough to power 60,000 houses.

EPRI's research of wave power concepts being pursued in the US and elsewhere have led it to suggest that the generation of electricity from this source "may be economically feasible in the near future". The Palo Alto research institute, which is funded by America's investor-owned utilities, says there are "compelling" reasons to pursue the technology including it being "one of the most environmentally benign ways to generate power". EPRI acids that offshore wave energy offers a way to minimise NIMBY issues that plague most energy infrastructure projects onshore, including renewable activities such as wind farming.

"Wave energy conversion devices have a very low profile and are located far enough away from shore that they generally not visible," it says. "Moreover, wave energy is more predictable than solar and wind energy and the ocean's processes that concentrate wind and solar energy into waves make it easier and cheaper to harvest (than onshore solar systems and wind farms)."

Not the least, wave power has the potential to be big business. Research has revealed that wave energy is a suitable renewable resource, apart from the Australian and western Europe coastlines, in North America, the Pacific islands, Japan, China, South America and Africa. It is estimated that about 20,000km of ocean coastline globally are suitable for harnessing wave power. The International Agency has estimated that it could supply between 10 and 50 per cent of the, world's power needs later this century.

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