PFI-TT: Energy-Efficient Smart-Privacy Windows made of Dynamic Crystals

The broader impact and commercial potential of this Partnerships for Innovation - Technology Translation (PFI-TT) project includes the development of inexpensive, energy-efficient window technologies and devices. Optical light transmission of such windows will be switchable by low-voltage electric fields within a fraction of a second. Beyond windows, other potential applications include coverings of greenhouses, skylights, and a large variety of electro-optic applications.

The societal outcomes include reduction of energy consumption, improved comfort of building inhabitants, reduced energy demand, and creation of new jobs associated with manufacturing of these new breeds of energy-efficient windows. The team will utilize demonstrations based on the project’s outcomes to contribute to the general public's appreciation of the importance of the energy efficient technologies.

The proposed project develops energy efficient windows capable of dynamically controlling transmitted light by applying low voltages (~1 Volt). Commercial and residential windows are the source of loss of about 40% of heating/cooling energy. The nanostructured liquid crystal technology promises to improve dynamic windows by controlling light transmission in the visible and near-infrared.

This control will be achieved using a thin layer of a liquid crystal with ordered metal nanoparticles dispersed within it, which can be continuously rotated or switched using low-voltage fields. The main goal of this project is to develop and test prototypes of inexpensive. electrically-switchable windows while solving technological hurdles related to the speed of switching and scaling their dimensions.

Skylights are the initial target market. The team will explore how these switchable devices can be engineered using nanoparticle-doped liquid crystals for applications in buildings within different climate zones. This application may lay the groundwork for a number of other technologies that rely on electrically-controlled molecular and nanoparticle organization at the mesoscale.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.