Real power from nothing but hot air

A one kilometre-high tower capable of producing enough energy for 200,000 homes has been approved by the Australian government and could be in operation within three years, subject to approval by the New South Wales state authorities.

In effect a giant chimney, it will generate electricity by drawing warm air from ground level through turbines. Its developer, EnviroMission, says the full-scale prototype, planned for a site on the border of New South Wales and Victoria, could be replicated in deserts throughout the world.

The company's chief executive, Roger Davey, said: "It's completely silent, it doesn't need any fuel, and the only by- product is hot air." [read more]