14 DAY TRIAL // Windows that allow light and heat levels adjusting are already available but Soladigm, the producing company, aims at making these "electrochromic" windows a lot cheaper and thus more affordable for home and office buildings use.
Having a large scale utilization of this type of windows is a good way of reducing heating and cooling bills, as they are capable of absorbing or reflecting light and heat just as you push a button.
The electrochromic window concept emerged a few decades ago, but constant technological evolution managed to improve the thin-film deposition equipment, the same that is used to make thin-film solar panels and flat panel display.
The company, based in Milpitas, California, uses a thin-film deposition process that makes conducting layers between two panes of glass and so the amount of sunlight and heat that passes through can be easily controlled.
The windows have two transparent conducting oxide films sandwiching an ion storage layer, an electrolyte and an electrochromic layer, all this between the two layers of glass.
When applying a low voltage to the conductive oxide it moves the ions out of the storage layer and across the electrolyte to meet with the electrochromic layer, and it is this collision that makes the electrochromic material to absorb or reflect light, and it also gives the window a tinted look.
For the window to lighten and let more light in, the voltage is reversed and the ions go back to the storage layer.
“We did a case study in five cities, and the average savings in commercial buildings are about 25 percent of the heating, ventilation, and air-conditioning energy use annually,” Rao Mulpuri, CEO of Soladigm says.
He adds that the trick to making electrochromic windows cheaply is having the right materials and latest manufacturing method.
Current electrochromic windows costs about $100 per square foot and even if Soladigm has not said how much future windows will cost, some say that the price could be lowered down to $20 per square foot.
An alternative might be the low-E windows, that manage the amount of light and heat that gets into a room as they have a metal oxide coating that reflects near-infrared light and allows most visible light to pass through, and they generally cost around $10 per square foot.
Both products can control the amount of heat from near infrared and make it possible to warm up a room in cold days, reports Technology Review.
“There might be time when you want light blocked but you want the near-infrared to get in. In the winter, you want light and the heat to warm up the house, so having the ability to switch both or independently will be ideal," Tom Richardson, a researcher at LBNL's Advanced Energy Technologies Department says.
The only question now is which one the lowest overall price and the highest quality.