Nanomaterials can help make windows more energy-efficient

ARGONNE, Illinois: A team of researchers at the US Department of Energy’s (DOE’s) Argonne National Laboratory is using nanomaterials to improve the energy efficiency of existing single-pane windows in commercial and residential buildings.

The nanofoam the team is developing – known as a nanocellular composite with super thermal insulation and soundproofing – uses gas bubbles less than 100 nanometres in diameter to block the transfer of heat and sound through glass windows while allowing visible light to pass through and maintain a clarity similar to normal windows.

“That’s really the trick, blocking the heat and sound transfer while maintaining transparency,” said Ralph Muehleisen, principal building scientist at Argonne. “It’s fairly simple to develop a coating that insulates, but getting one that is thin and you can still see through is a substantial technical challenge.”

The nanofoam, which will be extruded into sheets about three mm thick, creates a thermal insulation effect by using the tiny bubbles to reduce collisions among gas molecules, thereby reducing the transfer of heat energy. When the bubbles are reduced to that scale, super thermal insulation becomes possible.

Single-pane windows make up 30-40 per cent of windows in the United States Single-pane windows conduct at least twice as much heat as double paned, so retrofitting all those windows could save consumers about US$12 billion a year in energy costs.

“This effort really shows the power of cross-cutting scientific collaboration,” said Matt Tirrell, who is Argonne’s Deputy Laboratory Director for Science and holds a joint appointment with the University of Chicago. “By bringing together these unique skillsets and facilities, we have the ability to make substantial breakthroughs that hold the promise to make a big difference in building energy efficiency.” — Newswise