They are more efficient, but at what cost?
A Silicon Valley startup unveiled a smart window product that gives building designers a promising new tool and improves building efficiency. View (formerly called Soladigm) officially introduced its auto-tinting window system made of a dynamic glass that tints based on building light and temperature. There have been many attempts to make windows that can change color to adjust light and temperature indoors, but these glass products are rarely used.
View says that its electrochromatic glass is durable and provides a reasonable payback on energy reductions and eliminating blinds. But shaving energy bills—typically, a 20 percent reduction in HVAC and lighting—aren’t the only draw. “The energy savings are tremendous but this is much larger than that. It’s a truly intelligent window system that allows for a fantastic user experience,” says CEO Rao Mulpuri. The glass allows people to sit in comfort next to the windows by reducing glare and heat when tinted and allowing as much natural light in as possible.
In a commercial setting, such as a hotel or store, the glass is connected to a building management system through a Wi-Fi network that measures occupancy & temperature and uses light sensors. A person can manually adjust the tint from a wall switch or a networked device or the system can be set to automatically adjust the low-voltage windows.
The core technology is a electrochromatic material and how it is applied to glass. Using physical vapor deposition techniques common in the thin-film solar or display industry, it sputters metal oxide gases onto glass to create a ceramic coating. The finished window includes wiring and a second glass pane. Using a ceramic material (which is abundant) makes the window coating durable, which has been a problem for other auto-tinting technologies.
View’s windows cost 50 percent more than plain windows, so it’s a premium product building owners need to be willing to pay more for. Building designers and architects will no doubt have many ideas on how smart glass can be incorporated into building facades or skylights. The key is demonstrating that its energy-saving features can justify the new technology. Existing electrochromic window designs cost around $100 per square foot. View has not disclosed how much its windows will cost, but it is estimated that View’s smart windows will cost around $20 per square foot.
More comparative analysis needs to be done of the cost savings on utilities as compared to the cost of the windows plus the additional electricity used to run the system.