APPLICATIONS OF TECHNOLOGY:
- Residential and commercial building industries
- Automobile industry
ADVANTAGES:
- Faster optical phase switching than state of the art
- More sensitive, stable response to subtle light and temperature changes
- Potentially more affordable than current technologies
ABSTRACT:
André Anders of Berkeley Lab has invented a method for creating cost effective, dynamic electrochromic windows. The “smart” window system uses a thin film of fast switching phase change material, typically used for opto-electronic data storage, to alter the spectrally selective transmittance, or optical property, of a transparent material such as coated glass. As a result, the window may be able to control the amount of sunlight passing through the glass to ultimately reduce a building’s air conditioning load in the summer and heating load in the winter. While conventional devices can take several minutes to darken or lighten in response to changing temperatures or varying degrees of ultraviolet or infrared light, this invention promises response times in microseconds—six orders of magnitude faster than conventional smart windows.
Unlike competing technologies that change a window’s optical properties by intercalating or exchanging ions between layers coated on glass, the Berkeley Lab system uses pulsed heating, a process that switches how much light a window absorbs or reflects, in conjunction with the novel application of phase change materials. This invention opens the door to mass production of phase change thin films for large area (square-meter scale) energy efficient windows, façades, skylights, roof panels, and automobile windows using less costly materials than conventional smart window methods. Furthermore, the new windows’ lifetimes may far surpass the current state of the art.
STATUS: Published patent application 20100225989 available at www.uspto.gov. Available for licensing or collaborative research.
DEVELOPMENT STAGE: Conceptual. This is very early stage research that will require a collaborative effort and significant R&D to commercialize.
SEE THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD:
Low Cost, Stable Switchable Mirrors: Lithium Ion Mirrors with Improved Stability, IB-1817
Transition Metal Switchable Mirrors, IB-1665
High Conductivity Single-ion Cross-linked Polymers for Lithium Batteries and Fuel Cells, IB-1553, 1554
Novel Electrochromic Device Controlled by Sunlight, IB-1235
Constricted Plasma Source, IB-1124
EnergyPlus: Energy Simulation Software for Buildings, CR-2118
REFERENCE NUMBER: IB-2669
