Second-Gen Smart Windows Inch Closer to Market

Smart glass – glass that allows users to control for glare, light, and even heat – has the potential to help buildings use energy far more efficiently. According to a recent report by Navigant Research, the smart glass market is set to grow more than 10-fold in the next decade, to $899 million in 2022 from just $88 million this year.

Many of these technologies are still at the early stages of development. But one of them – a second-generation product with a unique convenience feature – is on the verge of a big step closer to commercialization.

Heliotrope has been working with Lawrence Berkeley National Laboratory to develop a technology that allows windows to separately control transmission of light and heat, the only product of its kind. “Decoupling light and heat coming through the window is unique to our technology,” Heliotrope’s president Jason Holt told Breaking Energy.

For more on how it works, see Smart Windows Just Got a Lot Smarter at Saving Energy

The window comes with three separate settings: bright, cool and dark. On the “bright” setting, the window functions just like any other window – it lets in both light and heat, both valuable commodities in colder climates.

On the “dark” setting, the window is effectively tinted, letting in only about 3-5% of the light without blocking the view to the outside. “If we can get below 5% light transmission, you could significantly cut out glare,” Holt said. “You may be able to do away with blinds altogether.”

The “cool” setting is “really the novelty that nobody else has”, said Holt. “That’s the state where you maintain all the light coming through the window, but you block the heat, and that has important consequences for folks in the architectural community.”

Maximizing natural light in an office building can offer substantial energy savings. Lighting accounts for about a third of a building’s energy consumption. “People don’t really appreciate how much you spend on lighting,” Holt said.

Cutting back on heating, air conditioning and ventilation needs  – which account for another third of buildings’ energy use – can amplify savings.

“It’s a smart window that offers a functionality that no other product on the market does,”  Holt said.

Getting the Glass to Market

To say that it’s on the market may be getting a little ahead of the game. Heliotrope plans to begin commercial sampling – independent evaluations of the technology by large glass companies – later this year. “It will help us in our future fundraising efforts and give us a lot of credibility,” said Holt. Sampling could last anywhere from 6-9 months to a few years.

And the actual marketing will be carried out by large glassmakers who buy the specialized film from Heliotrope. “Our approach is to actually deal with glass guys further upstream to get to market much more quickly,” said Chief Executive Mike Clary. He estimated 18-24 months before its technology is incorporated into product cycles.

Assessment of the actual impact on energy use – how much buildings stand to save – is ongoing. Heliotrope is working with Lawrence Berkeley, and will use some of the data produced in commercial sampling, to determine total potential impact in terms of kilowatt hours saved on various types and sizes of buildings in different geographic locations.

Heliotrope’s windows will come with a cost premium over traditional windows, much like other varieties of electrochromic glass. Navigant has identified price as the primary barrier to adoption of smart glass.

But the company is confident that its production costs are going to be half – or less than half – of those of first-generation electrochromic windows. “All of the materials that comprise our special films can be made into inks that can be deposited using really cheap tools,” he said.

And the products Heliotrope offers will be geared at new construction, at least at the initial stages. “The biggest energy impacts from this technology can be realized when it’s specified as part of a holistic building design process,” Holt said.. “The way we’re making this doesn’t lend itself to a retrofit opportunity.”