How Australia got hot for solar power

Down under, they’re all over alternative energy – starting with a 1,600-foot tall “solar tower” that can power a small city.

Rattling down a red dirt road on the edge of the Australian outback, Roger Davey hits the brakes and hops out of a rented Corolla. With a sweep of his arm, he surveys his domain – 24,000 acres of emptiness stretching toward the horizon, the landscape bare but for clumps of scrubby eucalyptus trees and an occasional sheep.

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.

CNN/Money