Smart High Tech Buildings Use Sunlight to Save Energy

Smart High Tech Buildings Use Sunlight to Save Energy
At Dallas/Fort Worth Airport, the lights are controlled by sensors that measure sunlight. They dim immediately when it's sunny and brighten when a passing cloud blocks the sun.

At a new middle school in Washington, D.C., the air conditioner shuts off when a window is open.

A wall of windows at a University of Pennsylvania engineering building has built-in blinds adjusted by a computer program that tracks the sun's path.

Buildings are getting smarter and the next generation of building materials is expected to do even more.

Windows could trap the sun's energy to heat hot water. Sensors that measure the carbon dioxide exhaled by people in a room could determine whether the air conditioning needs to be turned up.

"More potential products have been invented in the last 15 years than in the entire prior history of architecture,' says Philadelphia architect Stephen Kieran. "We're only beginning to tap the potential of those materials.'

The new materials and technology are being used in a wave of buildings designed to save as much energy as possible. They range from old ideas, like "green roofs,' where a layer of plants on a roof helps the building retain heat in winter and stay cool in summer, and new ideas, like special coating for windows that let's light in, but keeps heat out.

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