Dynamic glazing with switchable solar reflectance for radiative cooling and solar heating

Dynamic control of sunlight entering a building through glazing panels (e.g., windows, curtain walls, and skylights) is essential for reducing building energy consumption. Here, we demonstrate a dual-mode glazing panel with switchable reflectance (89% versus 17%) via reversible electrodeposition of a silver film on a transparent glass of the glazing. In cooling mode, the silver film-coated glazing, functioning as a radiative cooler, achieves net cooling power of 20–60 W/m2 on a summer day with direct solar irradiance of 560–970 W/m2. In heating mode, transparent glazing absorbs only 13% and allows ∼70% of sunlight to shine through, providing a net heating power of around 400 W/m2 on a winter day with solar irradiance of 540 W/m2. Simulations show that employing such dynamic glazing panels in a medium-size office building (∼5,000 m2) could save up to 23% annual heating/cooling energy consumption under the local climates of 15 U.S. cities.