Science Daily June 27, 2024
Vertical facades of buildings mostly see terrestrial features that become broadband-radiative heat sources in the summer and heat sinks in the winter. The resulting summertime terrestrial heat gain by buildings overwhelms their narrowband longwave infrared (LWIR) radiative cooling to space, while the wintertime terrestrial heat loss causes overcooling. A team of researchers in the US (Princeton University, Oak Ridge National Laboratory, UCLA, Arizona State University) showed that selective LWIR emitters on vertical building facades could exploit the differential transmittance of the atmosphere toward the sky and between terrestrial objects to achieve higher summertime cooling and wintertime heating than conventionally used broadband emitters. The impact of passive thermoregulation was comparable to that of painting dark roofs white and was achievable with both novel and commonplace materials. According to the researchers their findings represented new and remarkable opportunities for materials design and untapped thermoregulation of entities ranging from buildings to human bodies… read more. Open Access TECHNICAL ARTICLE