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A 2,600-foot tower planned for the Arizona desert will be the
world's second tallest structure and will be able to power 100,000 homes through
hot air alone.

The solar updraft tower, designed by EnviroMission, will work by collecting hot
air as it rises from the heated ground surrounding it. The very tall, narrow
tower increases the strength of the hot air flowing upward, where it will turn
32 turbines along the way.