Growing panes: will smart glass stimulate mineral demand?

By Cameron Perks
Published: Thursday, 17 May 2018

As modern architecture increasingly looks to smart glass for its unique, functional and environmentally friendly properties, Industrial Minerals correspondent Cameron Perks takes a look at how this may stimulate demand for glass minerals, as well as certain metal oxides.

On reading the words "smart glass" you would be forgiven if the first thing they brought to mind was Google Glass or some other niche technology from Silicon Valley that is likely to fade into the fog of history.

But smart glass is much more than the latest craze, and even more than just the latest innovation. In fact, the first implementation of smart-glass technologies was made in 1982 by Gentex, when it introduced the world’s first automatically dimming rear-view mirrors for cars.

And while it has not made its way into my own car windows, popular magazine New Scientist reported in 1989 that General Motors had filed a European patent application (No304 198) for "smart windows which automatically control the transmission of light and heat," made of glass which "darkens and bleaches when an electric current is fed through it from [a] light sensor and control circuit."

While it may be "old" technology, smart glass is experiencing a resurgence in popularity because of the 21st century demand for building materials to be more multifunctional, to have "unique" properties and, in the case of architecture, to help to build environmentally sustainable spaces for living and working.

Smart glass benefits

A study published in 2017 by Piers MacNaughton and his multidisciplinary team at Harvard University in the United States found that "improved indoor environmental quality is associated with better health outcomes," and that workers from "green certified buildings" scored significantly "higher on cognitive function tests - controlling for annual earnings, job category and level of schooling - and had 30% fewer sick-building symptoms than those in non-certified buildings."

Smart glass is "about 70% more energy-efficient during summer and 45% more efficient in the winter, compared with standard dual-pane glass," making it an integral part of green-building architecture, according to a recent article by RMIT University in Melbourne, Australia.

In this article, associate professor Madhu Bhaskaran explains how she and PhD student Mohammad Taha have developed a vanadium oxide-based self-modifying material which will help smart glass to become greener and more automated. Prof Bhaskaran explains that their coating "doesn’t require [the input of] energy [unlike existing technology] and responds directly to changes in temperature."

The article used a smart-glass retrofit of New York City’s Empire State Building in 2010 as an example of how economic and environmental benefits were already being drawn out of existing technology. This retrofit resulted in "reported energy savings of $2.4 million and… carbon emissions [reduced] by 4,000 metric tonnes [per year]."

More recently, in 2017 industry major SageGlass, whose parent company is Saint Gobain, installed its smart glass at the University of Colorado Boulder, in the US. In the same year, View Inc announced that it will install 66,000 square feet of dynamic glass at San Francisco International Airport, while Kinestral Technologies unveiled the first installation of its new Halio smart tinting glass at the San Francisco office of Alexandria Real Estate Equities.

Looking to future glazing design trends, SageGlass thinks that large-scale installations, expansion into additional global markets, and the increasing use of smart glass in the hospitality sector will create the majority of new business opportunities.

Raw materials supplies

So how will these trends affect raw material supplies? Since the innovation in smart glass is in the thin metal-oxide layer within the glass, it might be logical to conclude that the demand for some metals is likely to rise. And while some of the technology being used in today’s products is proprietary, we know that oxides of tungsten, molybdenum, vanadium, indium and titanium can be electrically stimulated to increase their light-absorption properties.

In the case of vanadium, RMIT’s announced technological breakthrough caught the eye of Vanadium Corp, a vanadium processing technology and exploration company, which reintroduced the work to the Toronto Stock Exchange. "Smart windows and energy storage are examples of the glaring need to address the global short supply of vanadium, [which is] only possible with more efficient and sustainable methods of production," the company’s chief executive officer, Adriaan Bakker, said.

European prices for vanadium pentoxide were $14.90-15.50 per lb in-warehouse Rotterdam on Friday April 20, according to Metal Bulletin’s assessment, down from $15.50-16.00 per lb one week before.

While Bakker’s conclusion may be logical, it may also be important to remember that the metal oxide layer used in smart glass is extremely thin. In the case of RMIT’s glass, the coating is 50-150 nanometers in thickness, which is thinner than a human hair.

But since 90% of all manufactured glass is comprised of silica, sodium carbonate (soda ash) and calcium carbonate (limestone), building retrofits and the increasing trend toward using glass in new buildings may mean that the growth in demand for these materials will continue.

Industrial Minerals assessed the price for soda ash, European, synthetic, dense and light, large contracts, ex-works at €190-210 ($227-251) per tonne on May 10, up from €180-200 per tonne on February 22. Prices moved up recently on tight supply in the European market.