- NET Web Desk
Researchers at Indian Institute of Technology (IIT)-Guwahati have developed an affordable and efficient ‘passive’ radiative cooling system that does not require electricity to operate.
This “Radiative Cooler” coating is a “electricity-free” cooling system that can be installed on rooftops and works both during the day and at night as a replacement for conventional air conditioners.
Passive radiative cooling systems operate by releasing heat absorbed from the environment as infrared radiations, which can pass through the atmosphere before being released into the cold outer space.
Majority of passive radiative coolers only work at night, and in order to work during the day, they must reflect solar radiation.
Till now, these cooling solutions have not yet been able to cool the room sufficiently during the daytime.
A research team of IIT-Guwahati led by Ashish Kumar Chowdhary, Research Scholar at the institute, under the supervision of Prof Debabrata Sikdar, Assistant Professor, Department of Electronics and Electrical Engineering, has designed and modelled these coolers, in order to address relevant issues and bring out more accessible and efficient radiative cooling system that can operate round the clock.
“Designing a passive radiative cooler for daytime operation is more challenging due to the simultaneous requirement of high reflectance in entire solar spectral regime (0.3–2.5 µm wavelengths) and high emissivity in the atmospheric transmittance window (8–13 µm wavelengths),” – stated Prof. Sikadar.
“These radiative coolers requiring no external energy sources for their operation could be one of the best alternatives to replace the conventional air conditioning systems used to cool buildings and automobiles in countries experiencing hot weather, such as India,” he added.
The theoretical design of the radiative cooling system are tested and verified against rigorous computer-based simulations.
This patterning-free design of radiative cooler is large-area compatible and hence, also less prone to imperfections during fabrication process, the release said.
“The team hopes this will reach the market once the large-scale prototypes are developed and tested for operational stability and durability under different climatic conditions. They are now working towards this,” the release added.
Meanwhile, the key benefits of this system over previous technologies are its lithography-free and large-area compatible design, which ensures effective cooling throughout the entire day without requiring the cooler to be positioned or angled toward the sun.
