Scientists have developed an all-season smart-roof coating that keeps homes warm during the winter and cool during the summer without consuming natural gas or electricity. Research findings reported in the journal Science point to a groundbreaking technology that outperforms commercial cool-roof systems in energy savings.

“Our all-season roof coating automatically switches from keeping you cool to warm, depending on outdoor air temperature. This is energy-free, emission-free air conditioning and heating, all in one device,” said Junqiao Wu, a faculty scientist in Berkeley Lab’s Materials Sciences Division and a UC Berkeley professor of materials science and engineering who led the study.

Today’s cool roof systems, such as reflective coatings, membranes, shingles, or tiles, have light-colored or darker “cool-colored” surfaces that cool homes by reflecting sunlight. These systems also emit some of the absorbed solar heat as thermal-infrared radiation; in this natural process known as radiative cooling, thermal-infrared light is radiated away from the surface.

Read more at DOE/Lawrence Berkeley National Laboratory

Image: Samples of an all-season smart-roof coating designed to keep homes warm during the winter and cool during the summer – without consuming natural gas or electricity. The device looks like Scotch tape, and can be affixed to solid surfaces such as a rooftop. Research findings by scientists at the Department of Energy’s Lawrence Berkeley National Laboratory point to a groundbreaking technology that outperforms commercial cool-roof systems in energy savings. (Credit: Credit Junqiao Wu, Lawrence Berkeley National Laboratory)