Passive radiative cooling: New material can keep buildings cool without the use of power – TomoNews
Engineers have developed a new system to help cool buildings in crowded cities without consuming electricity.
The device, created by a team at the State University of New York at Buffalo, uses passive or radiation cooling technology so it doesn’t require electricity to operate. The system allows efficient heat dissipation throughout the day, even in densely populated urban areas.
The system is made of an aluminum film coated with an inexpensive transparent polymer (polydimethylsiloxane). This sheet is folded into an inverted cone and sits inside a foam box covered with a solar absorbing material that acts as a solar shelter..
Aluminum reflects sunlight, while polymer absorbs heat from the surrounding air and transfers this energy through the atmosphere into the open space in the form of infrared radiation, while remaining cool.
Since the functional sheet is folded in the shape of a cone, it concentrates radiation, directing it in a narrow stream upward, which ensures efficient operation in urban environments.
When placed outdoors during the day, a heat-emitting film and shelter from the sun helped reduce the temperature in a small enclosed space by 6 °C. At night, this figure increased to about 11 °C. However, due to the small size of the device (45.72×25.4×25.4 cm), it will be necessary to install numerous system nodes on the roof to cool the whole building..
Recently another team of researchers has created a new type of durable wood material for passive cooling of buildings, the temperature of which is always 5-6 °C below ambient air.
text: Ilya Bauer, photo: University at Buffalo