'Smart' window design instantly changes tint depending on air temperature
Korean scientists create energy-saving windows that reflect heat in the summer and absorb it during the winter.
Thu, Sep 29, 2011 at 03:37 PM
Korean scientists have developed a new type of smart window that can instantly change from being transparent to opaque based on changes in air temperature, reports the BBC.
The new technology provides a novel way of automatically regulating temperature inside houses and buildings, with an aim at significant energy savings throughout the year.
"Smart windows can prevent the inside of a building from becoming overheated by reflecting away a large fraction of the incident sunlight in summer," wrote the Korean research team in a recent article in ACS Nano. "Alternatively, they can help keep a room warm by absorbing the sun's heat in winter."
The technology is a vast improvement over similar kinds of tint-changing windows that already exist. For instance, previous designs were built with charged ions that cause the windows to shift from opaque to transparent when electric current is applied. By contrast, these new, smarter windows are built with a special polymer made from counterions instead, as well as with solvents such as methanol. Not only is the new design cheaper and less toxic, but it's much more efficient, too — capable of shifting from opaque to transparent in a matter of seconds.
Perhaps the best feature of the new windows is that they don't require manual operation. By changing instantly based upon outside air temperature, they are geared toward self-regulated, and thus maximally efficient, energy savings.
"Until now, the numerous technologies developed not only have been chemically unstable, prohibiting their use in long-term switching applications but have been accompanied by the use of expensive special equipment and complicated harsh processing conditions," added the report.