Outback's solar tower will reach for the sky

MELBOURNE - The firm behind a plan to build a power-generating solar tower - touted as the world's tallest structure - in Outback New South Wales is to sign an agreement to buy the site.

Melbourne-based Enviromission will buy a 10,000ha slice of Tapio station at Buronga, 25km northeast of Mildura, to build the 1km tower.

Enviromission chairman Roger Davey would not confirm the purchase price, but said it was "more than A$1 million" ($1.1 million).

The agreement will be signed in Mildura, 550km northwest of Melbourne, before an audience of community leaders.

"This formalises the commitment between Enviromission and the vendor subject to planning issues, so we can move ahead with confidence," Davey said.

"It confirms our commitment to the site and the Sunraysia region for the first solar tower."

The mammoth project, worth hundreds of millions of dollars, will be built by the end of 2009.

The reinforced concrete tower will cover an area the size of the Melbourne Cricket Ground's surface at its base and will be surrounded by a "greenhouse" of glass, polycarbonate and polymer.

Air at 30C at the edge of the glasshouse is heated up to 70C at the centre, where the tower draws it through 32 turbines to the cooler air above.

The power station will produce up to 200 megawatts of electricity - enough for a city the size of Hobart - and can generate 24 hours a day.

Enviromission floated on the Australian Stock Exchange in 2001.

Its major investor is the owner of the solar tower technology, US company SolarMission Technologies.

Enviromission has the exclusive Australian rights to the technology, first developed on a much smaller scale in Spain in the early 1980s, using a German design.

A group of Chinese investors has formed a joint venture to invest a further US$2 million ($2.88 million) in the project's development.

There are also plans to invest a further US$8 million for development of a solar tower in China.

Enviromission will be a part owner of a global intellectual property company that will benefit from solar towers built around the world, Davey said.

The pre-feasibility study was completed successfully in February last year.

- AAP