Building Efficiency

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.

Eclipse Energy Systems will further develop its proprietary transparent electrical conductor material (EclipseTEC) for use in low-emissivity (low-e) window films. Transparent, low-emissivity coatings improve building energy efficiency by reducing heat loss through the windows. Over the course of the project, the team will transfer their present technology for depositing EclipseTEC films to scalable manufacturing processes while preserving the desirable optical and low-e properties.

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 University of Colorado, Boulder (CU-Boulder) with its partners will develop a flexible window film made of nanostructured cellulose. The film can be applied onto single-pane windows to improve their energy efficiency without compromising transparency. The team will be able to economically harvest cellulose needed for the films from food waste using a bacteria-driven process. The cellulose will self-assemble into liquid crystal type structures that selectively reflect infrared light (or heat) while transmitting visible light.

The University of California, Los Angeles (UCLA) will harness advances in nanotechnology to produce thermally insulating transparent barrier (THINNER) coatings to reduce heat losses through single panes of glass. The porous coatings consist of multiple layers of silica/titania films that can simultaneously control the transmission of heat, light and thermal radiation. The internal structure of the coatings is determined by a polymer lattice that is later removed. This leaves a robust porous oxide layer that is transparent and thermally insulating.

Virginia Commonwealth University (VCU) will develop innovative methods to produce aerogel-on-glass windowpanes for window retrofits. Silica aerogels are porous materials that can be used to control heat transfer across windows. However, widespread use of silica aerogels in windows has been limited by their mechanical fragility, difficulties with transparency, and high manufacturing costs. The team will use newly developed cross-linked aerogels that significantly improve the mechanical strength and durability of aerogels.

NanoSD, with its partners will develop a transparent, nanostructured thermally insulating film that can be applied to existing single-pane windows to reduce heat loss. To produce the nanostructured film, the team will create hollow ceramic or polymer nanobubbles and consolidate them into a dense lattice structure using heat and compression. Because it is mostly air, the resulting nanobubble structure will exhibit excellent thermal barrier properties.

IR Dynamics will develop a low-cost nanomaterial technology to be incorporated into flexible window films that will improve thermal insulation and solar heat gain. The team’s nanomaterial will incorporate two materials. First, low-cost nanosheets will increase thermal resistance. Second, a new type of nanomaterial will allow heat, in the form of infrared radiation (IR) from the sun, to pass through the window when it is cold outside, helping to warm the room in cold weather. When it is hot outside, the material will block the solar IR from passing through the window and warming the interior.

Triton Systems will develop and demonstrate a high efficiency windowpane system that will encourage retrofitting of single-pane windows. Triton's Multifunctional Glazing System (MGS) will potentially provide a better balance of performance with cost and weight versus double-pane insulated glass units. The system combines a nanoparticle-polymer composite film with an insulating layer of a porous material filled with air, to provide thermal insulation. The team will enhance the pane’s durability by incorporating a nanocomposite edge seal.

The University of Alabama and their partners will develop a new testing and validation protocol for advanced occupancy sensor technologies. A barrier to wide adoption of new occupancy sensors is the lack of rigorous and widely accepted methodologies for evaluating the energy savings and reliability of these systems. To address this need, the Alabama team will develop a testing protocol and simulation suite for these advanced sensors.