Window furnishings could become a thing of the past if researchers in the US can get a new “smart glass” technology off the ground.
Researchers at the US Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a smart glass which can monitor and adjust heat transfer depending on the application of voltage.
Smart glass is designed to remain transparent blocking heat or has the ability to darken and reduce sunlight glare. The technology has been praised as a bold energy efficient solution for glass building facades, particularly in large urban skyscrapers.
"Smart windows are able to dynamically control the amount of heat and light from the sun that enters a building,” said Berkeley Lab scientists and lead author of the research Delia Milliron in a video describing the technology. “This is useful to improve comfort for building occupants and also to save energy that is used for thermal control and artificial lighting.”
The dynamic coating technology features a new "designer" electrochromic material made of Nano crystals of indium tin oxide embedded in the glass. A similar process is used to make auto-tinting eyeglasses.
Milliron also discussed the benefits of choosing to embed Nano crystals into the glass over “single phase” materials such as amorphous or crystalline, noting that researchers were “able to control the transition of heat and light from the sun independently but at the same time the particles are so small so when they’re spread across the window pane they’re invisible to your eye.”
According to a public release from the DOE/Berkeley Lab, Milliron and her team were able to create three states with the smart glass: fully transparent; blocking near-infrared light; and blocking both visible and near-infrared light.
With a global skyscraper boom and growing government pressure for the built environment to reduce carbon emissions, the technology could have application in buildings in a bid to reduce energy costs and contribute to carbon reduction.
"It’s become very in vogue to have a whole lot of glass on your facade, and that creates a problem from an efficiency perspective – you can’t control the heat,” Milliron said.
Currently, energy loss through windows represents four to five per cent of the US’ total annual energy consumption, equating to $50 billion dollars in energy costs annually According to Howdy Goudey, a scientist with Berkeley Lab's Buildings Energy Efficiency Program.
“Smart Windows have the potential to dramatically reduce this energy use associated with windows by adjusting to the optimal properties under all environmental conditions,” he said.
With building facades representing up to 20 per cent of a building's construction costs, concerns have been raised over the price of smart glass. Milliron, however, is confident the cost could be brought down to produce a glass that is just 10 to 15 per cent more expensive than a standard window.
While smart glass has not been perfected for release to the market, with price points and material choices still up in the air, the researchers are thrilled with their findings and the opportunities for the built environment.
"The most exciting part has been taking this project all the way from synthesising a new material, to understanding it in great detail, and finally to realising a completely new functionality that can have a big impact on technology," said Milliron.