Energy-efficient ways of cooling buildings and vehicles will be required in a changing climate.
Energy-efficient ways of cooling buildings and vehicles will be required in a changing climate. Researchers at Linköping University have now shown that electrical tuning of passive radiative cooling can be used to control temperatures of a material at ambient temperatures and air pressure. The results have been published in Cell Reports Physical Science.
"To cool buildings, for example, traditional air conditioning is mainly used today, which requires large amounts of energy and uses environmentally hazardous refrigerants. With the help of passive radiative cooling, the cold of outer space could be used to complement normal ACs and reduce energy consumption," says Magnus Jonsson, professor and leader of the Organic Photonics and Nano-Optics group at Linköping University.
Passive radiative cooling utilizes that thermal energy can leave an object in the form of infrared radiation. All objects emit heat as infrared light – trees, buildings, water and even humans.
Different types of materials emit different amounts of infrared heat. This depends on the ability of the material to absorb infrared radiation – the better it is at absorbing infrared heat, the better the material is at emitting the heat. For example, ordinary white writing paper is good at absorbing infrared heat and, consequently, at emitting it. By contrast, metals are rather bad at it, as most of the heat is reflected.
Read more at Linköping University
Image: Debashree Banerjee, principal research engineer, Magnus Jonsson, professor and Mingna Liao, PhD student are part of the research group that, among other things, explore the possibilities of passive radiative cooling. (Photo Credit: Thor Balkhed)
