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Cool workers
Cool workers
Today's offices blow highly chilled air from the ceiling, wastefully cooling the entire space. Here air doesn't need to be as cold, since it circulates from the ground up.

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Last updated December 03 2008: 10:34 AM ET
Eco-friendly city of the future The Emirate of Abu Dhabi begins construction on its green city, Masdar. See the plans for this $15 billion undertaking. More video