Have you seen windows that change colors to adjust the amount of light and heat that enters the room? Such technology does exist, and you can see it for yourself at a hotel in downtown San Francisco this week.
The W Hotel is showing off electrochromic windows, or “smart windows,” made by View, a startup that until recently was called Soladigm. The dual-pane electrochromic windows contain two transparent conducting oxide films sandwiching an ion storage layer, an electrolyte, and an electrochromic layer. Applying a low voltage to the conductive oxide pushes the ions out of the storage layer and through the electrolyte to meet with the electrochromic layer. The meet-up prompts the electrochromic material, which contains tungsten oxide, to absorb or block light. It also causes the material to darken and give the window a tinted look. Reversing the voltage sends the ions back to its storage layer and causes the window to lighten in color and let more light in.
The technology makes it possible to cool or warm up a room and thereby save the costs of using air conditioning or heater to control the indoor temperatures. But getting the conducting materials to work just right and allow for a fine control of lighting and heating is difficult. Because electrochromic windows aren’t widely used, they also are about 50 percent more expensive than the conventional dual-pane windows with coatings that filter out some of the ultra-violet radiation, said Rao Mulpuri, CEO of View.
“But this is more than a window. It’s an intelligent system that eliminates the need for blinds or shades and controls heating,” Mulpuri said.
The Milpitas, Calif., company estimates that its technology could reduce the amount of energy for heating and cooling of a commercial building by 20% over a 12-month period, or 25% during the hours of the day when electricity use is at its highest. Exactly how much savings View’s technology will achieve will depend on a variety of factors, including the location and orientation of the building and windows and the number of sensors and other electronic equipment that allow for manual or automatic adjustments of the windows’ filtering ability.
View built its first factory for mass production in Mississippi and began shipping to customers toward the end of the third quarter this year, Mulpuri said. The startup, founded in 2007, has raise $124 million in equity since its inception.
Mulpuri declined to disclose the production capacity of his factory, so it’s hard to gauge the demand for View’s windows. He also declined to name customers except for the W Hotel. The Mississippi factory has room for expansion if the company signs up more customers, he said.
The company has U.S. customers, and it’s concentrating on the European market as well. Europe will be a major market for electrochromic windows because the costs of producing energy are generally high there, and Europeans are more willing to pay a premium for products that will make them more energy efficient and help them reduce their carbon footprint. Mulpuri said.
The installation at the lobby of the W Hotel in San Francisco will feature View’s smart windows and an interactive display to explain how it works.