Wild Antarctic Winds to be Harnessed for Power

CANBERRA, Australia, August 22, 2001 (ENS) - Australia is embarking on an ambitious $US2.3 million program to take wind power further than it has ever been, by harnessing Antarctic gales for full scale electricity generation.

A wind farm is to be built at Mawson in Eastern Antarctica to meet much of the station's energy demand by slicing turbine blades into the katabatic winds that howl off the polar ice cap daily.

Towers will be built to withstand gusts of up to 300 kilometers per hour, and generate power in winds up to 130 kilometers per hour before they automatically shut down. Such demands are higher than anywhere else, according to project officials.

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Ice and stars at the South Pole (Photos courtesy Michael Burton, School of Physics, University of New South Wales)
"No existing turbine does this," said Peter Magill, of the Australian Environment Department's Antarctic Division. "The average wind we have at the site is potentially the strongest in the world. It was very difficult to find a manufacturer who was willing to sell us a turbine that could stand that."

Under the project, three 34 metre high towers, each capable of generating 300 kilowatts of power, will be built at Mawson among existing station buildings that line a horseshoe shaped granite natural harbour. Construction is to start next summer, and be completed the following season.

The 30 metre diameter blades will be built to chew through average annual winds of 43 kilometers per hour (kmh). This compares to what the Australian Bureau of Meterology said was an average annual wind speed of 5.0 kmh in central Melbourne, and 9.6 kmh at Sydney Airport.

Like other turbines, Mawson's will be designed to 'feather' their blades - exposing less surface area as winds strengthen. But whereas the latest generation of machines internationally shuts down automatically at winds of around 90 kmh, these will be built to continue.

"No other machine currently operating in the world would carry on at these speeds," said Alan Langworthy, managing director of the contracted firm, Powercorp. "This is the leading edge."

Among the engineering challenges, project builders must first come up with a way of fixing the towers through concrete into Mawson's granite so they are stable. The maximum gust recorded in 50 years of Australian occupation of the station is 252 kmh.

The towers and machinery to be built by German company Enercon will look similar to any that might be found today outside a European town.

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Mt Erebus and Castle Rock, Antarctica
But Langworthy said they would have to be strengthened, not only against the wind, but the effects on steel of cold temperatures. Their inner workings must also be sealed against the entry of fine blizzard blown snow.

He said the Enercon machines also had advantages because they were gearless, instead using a ring generator that rotated at the same speed as the propellor. The computer-linked "brains" of the machine is being developed by Darwin-based Powercorp, which has partnered Enercon in large scale Australian projects.

Most nations in Antarctica are experimenting with wind power in, but Mawson's will be ten times the capacity of the next largest, a 30 kilowatt machine at a German station.

Currently up to 800,000 litres of special Antarctic blend diesel fuel is shipped to Mawson yearly to generate light, power and heat. This project is intended to replace up to 80 per cent of fuel-generated power, and Mr Langworthy said technology was being developed to take it the next step towards 100 per cent replacement.

Australian Environment Minister, Senator Robert Hill, said the use of diesel power at Australia's three Antarctic stations was far from ideal. "The use of fossil fuel requires that it be transported from ship to shore and stored at stations before being used, and while we have minimized the risks of spillage, it is always there," Hill said.

The single major spill at an Australian station occurred at Casey in 1990, when 90,000 litres leaked out of a storage tank, forcing expeditioners out in minus 20 degree temperatures to attempt a clean-up.

Environmental assessment of the wind power project was conducted internally by the Australian Goverment, rather than being submitted for international approval through Antarctic Treaty mechanisms. Magill said the assessment concluded there was little risk of bird strike, from either ground nesting snow petrels or predatory skuas.

{Published in cooperation with The Antarctican}