An Australian power company is planning to build the world's tallest structure - a solar tower - in the middle of the outback. The project is part of a global campaign to encourage the use of more renewable energy. Enviromission says the tower, at a proposed height of 1,000 metres (3,300 ft), will be more than twice the size of the world's current tallest freestanding building, the Canadian National Tower in Toronto. The one billion Australian dollar (US $0.56 bn) project is being backed by the Australian Government, and is expected to be completed in 2006 in the remote Buronga...
