A Breakthrough from KAIST
In a major step toward sustainable urban living, scientists at the Korea Advanced Institute of Science and Technology (KAIST) have developed a next-generation smart window that not only drastically cools indoor environments but also reduces harmful light pollution. Led by Professor Moon Hong-cheol, the research team introduced a novel system called RECM, short for Reversible Electrodeposition and Electrochromic Mirror.
Three Modes, One Smart Solution
Unlike conventional smart windows that only tint the glass, RECM adjusts both light and heat transmission through three electronically controlled modes. The window can remain transparent like normal glass, switch to a deep-blue tinted state that absorbs most light, or enter a highly reflective mode where a silver layer forms to block both heat and sunlight. What’s remarkable is that this third mode also absorbs excess glare—making it safe for pedestrians outside, a common flaw in many reflective windows.
Cooling Performance That Speaks for Itself
In experimental model houses, the results were striking. A structure using regular glass reached temperatures as high as 58.7°C (around 137.7°F) within 45 minutes. However, with the RECM window in its most protective mode, the interior only rose to 31.5°C (approximately 88.7°F), marking a staggering 80°F drop. This highlights its potential in slashing cooling costs and making indoor spaces more comfortable in hot climates.
A Vision for Smarter Cities
Beyond energy savings, the smart window’s ability to reduce external glare addresses growing concerns about urban light pollution, which can affect both ecosystems and human health. The study was published in ACS Energy Letters and has been praised for tackling real-world issues often overlooked in smart window design.
With its ability to regulate light, block heat, and reduce glare, the RECM system could soon transform the way buildings manage energy and interact with the urban environment.
