Transparent Thermochromic Smart Window Films

Lead Performer: Argonne National Laboratory – Argonne, IL; Partners: National Renewable Energy Laboratory – Golden, CO, Lawrence Berkeley National Laboratory – Berkeley, CA, Washington State University – Pullman, WA

Buildings

October 7, 2021

Lead Performer: Argonne National Laboratory – Argonne, IL
Partners:
-- National Renewable Energy Laboratory – Golden, CO
-- Lawrence Berkeley National Laboratory – Berkeley, CA
-- Washington State University – Pullman, WA
Project Term: July 31, 2019 – September 30, 2020
Funding Type: Funding Opportunity

Project Objective

An emerging and highly promising concept to reduce building energy consumption is through the development of a “smart” window based on VO2 (vanadium dioxide) material. VO2 is a next-generation glazing material that allows visible light to go through the window while selectively blocking near-infrared (NIR) solar radiation. VO2 is particularly suited for energy-efficient window applications as its modulation of solar radiation only occurs in the invisible NIR portion of the spectrum, where more than half of solar radiation energy is contained.

This project aims to develop a thermochromic dynamic window film that will achieve revolutionary optical and solar modulation performance at a low cost. This proposed smart film is based on ultra-small M-phase VO2 nanoparticles embedded into a low-cost transparent polymer matrix. The novel smart film will incorporate three distinguished features:

  1. Self-regulating and selective transmission of the majority of NIR solar radiation depending on the environmental temperature
  2. High visible light transparency
  3. Enabling a multifunction material that can provide smart-controlling for both solar radiation and thermal insulation when a thick and porous matrix is applied

Project Impact

This project will design and manufacture a new generation of smart and highly efficient thermochromic dynamic window films that can be used for both retrofits and new windows. The resulting windows will have improved solar modulation, which will provide energy-efficiency benefits, all while maintaining high levels of daylight and unobstructed occupant views to the outside. To keep the windows cost competitive, the targeted cost to manufacture the smart window film is less than $3 per square feet.

Contacts

DOE Technology Manager: Marc Lafrance
Lead Performer: Ralph Muehleisen, Argonne National Laboratory

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