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.
A wall of windows at a University of Pennsylvania engineering building has built-in blinds (百叶窗) controlled by a computer program that follows the sun's path.
Buildings are getting smarter -- and the next generation of building materials is expected to do even more.
Windows could catch the sun's energy to heat water. Sensors that measure the carbon dioxide breathed out by people in a room could determine whether the air conditioning needs to be turned up.
Many new materials and technology have been designed in the last 15 years. They now being used in a wave of buildings designed to save as much energy as possible. They include old ideas, like "green roofs," where a belt of plants on a roof helps the building keep heat in winter and stay cool in summer, and new ideas, like special coating for windows that lets light in, but keeps heat out.
As technologies such as sensors become cheaper, their uses spread.
The elevators (电梯) at Seven World Trade Center, which is under construction in New York, use a system that groups people traveling to nearby floor into the same elevator, thus saving elevator stops. People who work in the building will enter it by swiping (刷) ID cards that will tell the elevators their floor; readouts will then tell them which elevator to use. The building also has windows with a coating that blocks heat while letting in light.
More new building materials and technology are in development. A Philadelphia building firm is now working on "smart wrap" that uses tiny solar collectors to catch the sun's energy and transmitters (传输器) the width of a human hair to move it. They are expected to change the face of the construction industry in the next ten years or so.

在达拉斯/福特·沃斯机场，所有的灯都是由能测量光线的传感器控制的。当阳光充足时它们立刻变暗，而当行云遮住太阳时又会变亮。
在宾西法尼亚大学，工程学大楼的一面玻璃墙上镶着由一套电脑程序控制的百叶窗，可以跟随太阳光线。
建筑物变得越来越智能化了。新一代的建筑材料有望更加智能化。
窗户可以吸收太阳能来烧水。传感器可以测量人们在室内呼出的二氧化碳量，以此判断是否要打开空调。
在过去15年中人们已经设计了许多新型的材料和技术。这些材料和技术正被用于众多建筑中，尽可能多地来节省能源。还包括一些传统的办法，像“绿色屋顶”。在屋顶种植植物带可以帮助建筑物保持冬暖夏凉。还有新的理念，像特殊的窗户贴膜。这种贴膜既能使阳光进入室内，又能起到隔热作用。
随着传感器之类的科技产品变得越来越便宜，它们的使用也普及起来。
纽约赛文世贸中心大厦里正在建设中的电梯就用一种可以把去临近楼层的人分组的系统来减少电梯停站的次数。在楼里工作的人们进入电梯前先刷ID卡，告诉电梯他们要去的楼层，然后电脑显示屏告诉他们应该使用哪一部电梯。楼里的窗户也有贴膜，在确保光线进入的同时可以隔热。
更多新的建筑材料和技术正处于研发当中。费城的一家建筑公司正在从事一种叫“smart wrap”的新材料研究。它用一个很小的太阳能接收器来接收太阳能，并且用细如发丝的传输器来传输太阳能。预计它们会改变未来十年左右的建筑工业的面貌。