United States. The Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) is working with manufacturers to bring to market a "super window" that is at least twice as insulating as 99 percent of windows for sale and will be ready to reach mass-market status.
The "triple thin" super window design doubles the thermal performance of current Energy Star-rated double-glazed windows and is seven times more insulating than a single-glass window. Berkeley Lab scientists have built and tested prototypes in the lab and now work with Andersen Corporation, a recognized door and window manufacturer, and separately with Alpen High Performance Products, which specializes in energy-efficient doors and windows. Both efforts seek to build and test improved prototypes suitable for large-scale manufacturing.
"Our approach is to attack the problem from two sides: to develop forces of both 'market attraction' and 'technology push,'" said Berkeley lab researcher Steve Stevekowitz, one of the inventors of the super window concept. "We're working with manufacturers to help them with their technology challenges, while also working with Energy Star, supply chain companies and utilities, who can offer rebates and incentives for consumer purchase. Our role is to be a catalyst to facilitate technological innovation and an evangelist in furthering DOE's energy efficiency mission."
Berkeley Lab has a long history of innovation in green building technologies; for example, it recently demonstrated the use of controlled lighting and shading to save energy and is working to make net-zero energy homes a reality. His work on high-performance windows dates back to the late 1970s, when the oil crisis catalyzed new ways to save energy. Berkeley Lab researchers at the time provided technical support for an entirely new product: a low-emissivity (or low emissivity) window coating that helps block long-wave infrared rays, to reach mass-market status. Low-e. emissivity coatings have saved the country billions of dollars in energy costs.
Selkowitz believes the slim new triple window could save even more. Current double-glazed windows consist of two layers of low-emissivity coated glass and argon gas in the space between the glass layers to further reduce heat transfer. Berkeley Lab's super window innovation is threefold: it inserts a third layer of very thin glass sandwiched between the two layers of a double-glazed window, adds a second low-emissivity coating, and replaces argon gas with krypton gas, which is much more insulating than argon in the very narrow space between the panels.
While there are other triple-glazed windows on the market, the virtue of this one is that it has the same width and virtually the same weight as existing double-glazed windows. This avoids having to redesign the window frame and blade, which would be a significant cost obstacle to market penetration.
Source: Berkeley Lab.
