University of California, San Diego (UC San Diego)

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 desirable or 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. Transparent adhesive products that can be applied directly onto existing windows could improve window energy efficiency and other important qualities without substantially affecting the window’s appearance.

The University of California, San Diego (UCSD) will develop a polymer-based thermal insulating film that can be applied onto windowpanes to reduce heat loss and condensation. The team's approach uses polymer-based coatings with specifically designed structures. Heat management is gained by the thermal conductivity of polymer and the internal thermal barriers. The coating is inherently low-emissivity, and also resists condensation and abrasion. The technology is initially designed for single-pane windows, but can be expanded in the future for use in double-pane windows, doors, and roofs, as well as potential applications in the automobile, aerospace, and military industries.

If successful, UC San Diego’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. The team estimates that wide implementation of its coating could reduce single-pane window heat loss by nearly 60% per year, which would conserve 1.2 quads of energy and save consumers $12 billion in energy costs. Consumers adopting these retrofits could also benefit from improved window performance, including greater comfort and condensation resistance in cold weather.