选择题：New Material Can Cool Buildings

New Material Can Cool Buildings

Researchers at Stanford University have developed a new material that can move heat out of buildings and into space. The material can cool buildings even on hot days.

The cooling material is a very thin sheet with many layers that could be placed on a roof like solar panels. However, instead of turning sunlight into energy as solar panels do, the material turns heat into infrared radiation.

Shanhui Fan is an electrical engineering professor at Stanford University. He says that the panels have a layer of material that is like sand. The panels also act like a mirror. They take heat out of buildings and reflect the light from the sun. Both the heat and sunlight are sent 100 kilometers into outer space.

The panels are cool to the touch, even in the sun. Researchers say they can reduce the indoor temperature to nearly 5 degrees Celsius below the temperature outside.

Mr. Fan says it is like having a window into space. He says the heat is sent directly into space without warming the air. Buildings in developing countries that do not have electricity or air conditioning could use the panels.In areas where one is off-grid,there is a significant potential benefit for storing medicine or even food. In many of these situations, being able to reduce the temperature is important. And this would provide a way to do it.

The Stanford researchers described their technology in the science publication Nature. They say the main problem is creating actual cooling systems using the high-tech panels. It may be possible to develop a cooling spray technology in the next three to five years that could be used on existing solid structures.



1. The material can cool buildings only on cold days.回答


2. The material turns heat intoinfrared radiation because it is a very thick sheet with many layers that could be placed on a roof like solar panels.回答


3. The heat of the buildings and sunlight are sent 100 kilometers into outer space by the panels.回答


4. The off-grid areas may use the panels to reduce the temperature of buildings to store medicine or even food.回答


5. A cooling spray technology may be developed in the near future that could be used on existing solid structures.回答