Smart Glass Windows Could Slash Nation’s Energy Bill

Inefficient windows are responsible for thousands of dollars in energy loss for both residential and commercial property owners. But new smart glass technology could allow windows to control sunlight and heat, drastically reducing energy costs across the country.

Imagine this: you wake up in the dark hours of an early winter morning, but instead of flipping on the lights, you flip a switch that sends a tiny electric current through the electrochromatic glass of your windows. The windows instantly turn from dark to transparent, allowing the warmth and natural light of the sun to flood your home.

Now imagine this: you’re the office manager of a company in scorching hot Phoenix, Arizona. Instead of cranking up the air conditioning when the sun warms the windows of your office to over 100 degrees, you simply flip a switch. Instantly the smart glass windows of your office building become tinted, blocking out the sun and helping to maintain a cooler temperature inside.

While these two scenarios might seem like science fiction, the technology that could make them a reality already exists–and it’s about to get a lot cheaper.

Smart window technology has “always been a premium product that, at $50 to $100 per square foot, has been too costly for most commercial and residential construction projects,” writes Steven Ashley of Txchnologist.com. But those prices are likely to fall in the next year, as a new, higher-volume manufacturing plant in Faribault, Minn. goes on line, and smaller smart window start-ups across the country begin to ramp up production.

So how does this dynamic glass actually work? I’ll let SageGlass, owner of the new Minnesota plant, to explain:

SageGlass’ electrochromic coating consists of five layers of ceramic material. Applying a low voltage of electricity darkens the coating as lithium ions and electrons transfer from one electrochromic layer to another electrochromic layer. Reversing the voltage polarity causes the ions and electrons to return to their original layer, causing the glass to return to its clear state.

Now, you might be wondering how installing electrified windows is going to help buildings reduce their energy consumption, rather than increase it. Ultra-efficiency is the answer: Experts say that powering 2,000 square feet of the color-changing glass—the equivalent of more than 100 windows—would require less power than illuminating a 60-watt light bulb.

And other companies, like Pleotint LLC, are working on ways to create smart windows from a temperature-sensitive film that grows more opaque as it absorbs solar heat—a passive technology called thermochromism–eliminating the need for even this small amount of electricity.

It might seem like futuristic technology, but researchers at the National Renewable Energy Laboratory (NREL), say if electrochromatic windows replaced all the conventional windows in the country. That’s about 5 percent of the nation’s entire energy budget.

Now that’s a bright idea.

Article by Beth Buczynski, appearing courtesy Crisp Green.

photo: Ctd 2005