Numerous U.S. buildings have single-pane windows that do not insulate the building or its occupants as well as double-pane units or other advanced windows. Single-pane windows are also inferior in condensation resistance and occupant comfort. However, complete replacement of single-pane windows with efficient, modern windows is not always feasible due to cost, changes in appearance, and other concerns. Retrofitting, rather than replacing single-pane windows, can reduce heat loss and save roughly the amount of electricity needed to power 32 million U.S. homes each year. One avenue is to replace just the pane itself with an improved windowpane. To be economical, these new types of manufactured windowpanes must be able to be installed into the existing window sash that holds the windowpane in place. To be adopted, they must improve window energy efficiency and other important qualities without substantially affecting the window’s appearance.
Project Innovation + Advantages:
Arizona State University (ASU) and its partners will develop new windowpanes for single-pane windows to minimize heat losses and improve soundproofing without sacrificing durability or transparency. The team from ASU will produce a thermal barrier composed of silicon dioxide nanoparticles deposited on glass by supersonic aerosol spraying. The layer will minimize heat losses and be transparent at a substantially lower cost than can be done presently with silica aerogels, for example. A second layer deposited using the same method will reflect thermal radiation. The windowpanes will also incorporate layers of dense polymers to control condensation and adhesion, while improving strength. The coating is designed to last more than 20 years and be resistant to damage from scratching, peeling, or freezing of water vapor within the pores of the silica layer.
If successful, ASU’s innovations will enable energy-efficient retrofits for the substantial remaining stock of single-pane windows in the United States. Retrofitting single-pane windows could produce significant economic and environmental benefits. These technologies could help reduce building energy consumption and save money for homeowners and businesses. Consumers adopting these retrofits could also benefit from improved window performance, including greater comfort and condensation resistance in cold weather and better soundproofing. Finally, by consuming less electricity, natural gas, and/or heating oil to warm a building, these technologies reduce the greenhouse gas emissions associated with using these energy sources.