EnviroMission Solar Tower

The world's first 'solar tower' is in the works for the Australian outback in the Buronga district of Wentworth Shire in New South Wales (NSW) and 25km north east of Mildura in Victoria. This 50MW tower at Tapio Station is just the beginning. Once the 200MW solar tower stations are commercialized in late 2007 or early 2008,

the energy output will represent an annual saving of more than 900,000 tonnes of greenhouse CO2 gases from entering the environment, with an outstanding Life Cycle Analysis of 2.5 years
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EnviroMission’s Solar Towers are proposed to generate electricity 24-hours a day. The power station will be at its most efficient on the hottest days when energy is most needed and peak prices are paid for electricity.

Re-radiation of heat present in the ground under the collector zone will provide the energy source during the night. This special feature enhances the commercial viability of the power station and gives EnviroMission a consistent competitive advantage over other forms of renewable energy generation(EnviroMission).

Here is an excerpt from an article by Todd Woody of CNN Business 2.0:

It's a dead-calm antipodean winter's day, the silence of this vast ranch called Tapio Station broken only by the cry of a currawong bird. Davey, chief executive of Melbourne renewable-energy company EnviroMission, aims to break ground here early next year on the world's first commercial "solar tower" power station.

"The tower will be over there," Davey says, pointing to a spot a mile distant where a 1,600-foot structure will rise from the ocher-colored earth. Picture a 260-foot-diameter cylinder taller than the Sears Tower encircled by a two-mile-diameter transparent canopy at ground level. About 8 feet tall at the perimeter, where Davey has his feet planted, the solar collector will gradually slope up to a height of 50 to 60 feet at the tower's base.

Acting as a giant greenhouse, the solar collector will superheat the air with radiation from the sun. Hot air rises, naturally, and the tower will operate as a giant vacuum. As the air is sucked into the tower, it will produce wind to power an array of turbine generators clustered around the structure.

The result: enough clean, green electricity to power some 100,000 homes without producing a particle of pollution or a wisp of planet-warming gases.

"We're aiming to be competitive with the coal people," says Davey, 60. "We're filling a gap in the renewable-energy market that has never been able to be filled before."

And although its final dimensions are still being tweaked, the 50-megawatt Tapio Station plant is just the small model: A half-mile-tall version is in the works for China, and EnviroMission is scouting sites in the American Southwest for other possible skyscraping power plants.