By now, you’re probably aware that your windows can play a pretty big part in your home’s energy use. Windows stand as a last defense against winds and heating and cooling loss—but the glass can also keep out unwanted solar heat as well. That means you need to pay attention to the energy measurements listed on your window’s specs. In particular, you’ll need to look at the solar heat gain coefficient, which tells you how much solar radiation the window allows through the glass.
The only problem? That number is a static measurement, so your windows let in or prevent the same amount of solar heat all year. But there are some parts of the year when that sun might be useful as passive heating, so you could use less energy in the winter, too. That idea is exactly why building experts developed dynamic smart glass for windows. This glazing can adjust tints to allow in more solar heat when you need it—and shade your home when it’s hotter out. They represent the next innovation in residential windows, so you may be seeing them in a home near you very soon. Here’s what you need to know about smart windows to get you ready to greet this burgeoning technology.
WiFi Connected Smart Windows
Lately it seems like everything in the home is getting the smart device treatment, so why should windows be any different? View, a dynamic smart glass manufacturer, produces electrochromatic glass that can be controlled automatically using WiFi connections. Thin wiring in the window can sense room occupancy, as well as the temperature and light inside and outside the building, and will adjust to compensate for these measurements.
However, the windows can also be networked to a smartphone to allow users to manipulate the window settings manually. View claims that proper installation can result in a 20 percent reduction in energy costs—and that the windows offer an attractive alternative to shades or blinds. However, keep in mind that with innovation comes an increased price. These models will cost you about 50 percent more than a regular window, which is a lot to pay to replace your shades.
What Is Electrochromatic Glass?
Smart windows are fitted with electrochromatic glass, glass panes which can change color according to certain conditions. This is the natural evolution from low-emissivity, or Low-E glass, where the glazing contains metallic coatings that reflect sunlight. Electrochromatic windows are made up of five microscopically thin layers. They contain two electrical contact layers, two electric conductor layers, and a separator. These layers allow lithium ions to travel throughout their interiors. When connected to a small charge, the ions can be moved through the layers to make the window appear more or less opaque.
Smart Glass Film
What if you like the proposed benefits of smart glass, but not the 50 percent price hike? You may have an option to retrofit your windows with smart window film. Glass Apps, another smart window maker, produces an adhesive smart film that can be applied directly to existing glass surfaces. The film is connected to a switch that allows you to toggle between clear and opaque settings. While this technology is still relatively new, it might be a better way to get some of the smartglass benefits without buying new windows for your home.
What Are the Pros and Cons?
While a lot more testing needs to be done to understand the specific benefits, most experts agree that smart glass has the potential to save you a lot of excess energy—which also means saving money on your utility bills. Shades and blinds just aren’t a practical (or particularly advanced) technology to prevent solar heat gain, so having a more precise system could do a lot of good here. And if you’re one of those people who can’t stand the look of conventional blinds, you may enjoy the blind-free views that come with the installation of smart glass.
On the other hand, this technology is still developing, so there are still kinks to work out. Most smart home products suffer from compatibility and user interface issues that make their setup and functioning difficult—at least for the time being. And as previously noted, there’s an issue with cost. Technology prices tend to fall as demand and availability increase, so if you’re interested in this technology, you may want to wait it out and see where the industry goes. After all, you don’t want to be stuck with the window equivalent of the LaserDisc when the DVD comes out.
No matter what kind of windows you choose for your next replacement project, taking into consideration how your glazing affects your home’s energy performance is a good place to start. Energy saving windows are always a “smart” bet.