Windows get smart in green building

Keeping people happy, or comfortable, is one of the many factors looked at under the Leadership in Energy and Environmental Design, or LEED, Green Building Rating System. But people like to have windows, and those windows can be a big problem for companies looking to save energy.

"It's the weakest energy link in a building," John Van Dine, chairman and CEO of Sage Electrochromics, told the Cleantech Group.

Sage Electrochromics, based in Faribault, Minn., which Van Dine calls the "Silicon Valley of the window industry," has a dynamically tinting window that can keep the view, but still block the heat and sunlight when needed.

"No one is going suggest building buildings, whether they're buildings we work in, we shop in, or our homes, without having glass windows in them. We're not going to live in a cave," said Van Dine.

Offering daylight and views counts for a couple of points under LEED. That's in addition to the points Sage's windows can get for keeping heat out, or in. The company's products can be controlled individually or as part of a smart energy control system.

"In certain installations and locations, you get the potential for a 60 percent reduction in lighting energy use in buildings," said Van Dine. He said the windows can have a 30 to 60 percent impact over current technology.

Sage has attracted the attention of investors, pulling in $16 million in Series B funding in June, led by Good Energies.

"The intent of the green buildings efficiency part of Good Energies is to invest in technologies that can collectively and cost effectively allow us to get to zero-net energy, zero-net carbon buildings, in the next four years," said Greg Kats, managing director at Good Energies.

Cleantech investor Good Energies, which has offices in Europe and North America, started its green building portfolio about four months ago. The group has also recently put cash into Windsor, Colo.-based Ice Energy (see the Cleantech Group's Ice Energy cools down power demand).

In addition to investment attention, Sage was also picked by the U.S. Department of Energy, out of 143 pre-applicants, to participate in its Loan Guarantee Program.

The DOE just announced the final regulations for the program, and invited Sage, along with 15 other finalists, to submit full applications for up to $2 billion in loan guarantees.

The company's technology has been selling since 2003, incorporated into Velux skylights for residential buildings. But now the company is moving into the commercial building market.

Sage built a manufacturing plant in Minnesota and brought its first product for the commercial market online in 2006. It's starting to deliver the new line this year.

Take a look at the company's factory here >>

"We have goals of over the next two years of bringing on our second generation manufacturing plant, which will dramatically lower the cost of our product, and create volumes that we then can get into larger segments of the construction industry," said Van Dine.

Windows that can tint automatically have been around for a while, but they're not designed to keep the view.

"It's really a privacy film product, and by applying a relatively high AC voltage, the glazing goes from a relatively clear condition to a milky condition," said Van Dine of the old windows.

"And so you don't maintain your vision through the window when it's switched into its opaque state."

Even when tinted, Van Dine said you never lose your view with the Sage windows. The windows take 3 to 5 minutes to tint, or untint, and use a low DC voltage.

The coatings are the key to the SageGlass technology. The panes are coated with five layers of ceramic materials, which have a total thickness that is less than 1/50 of a human hair.

When voltage is applied, ions travel from one layer to another layer, where a reversible solid-state change takes place, causing the coating to tint and absorb light.

Reversing the polarity sends the ions back to their original layer, clearing the glass. And you won't be stuck in with the tint if the power goes out. When power is removed, SageGlass gradually reverts to the clear, untinted, state.

That glazing technology attracted the attention of the venture division of Santa Clara, Calif.'s Applied Materials, the world's largest maker of semiconductor production equipment, as well as the attention of Belgium-based Bekaert, which makes advanced materials and coatings.

Those two companies were part of the Series B funding round.

"We are active in joint development programs," said Van Dine.

Kats of Good Energies, who sits on the board of Sage and Ice Energy, said green building is about 5 percent of new, non-residential construction in the U.S. He said it's a $12 billion a year market, growing 40 to 50 percent a year.

"A year from now we'll have eight or nine investments," in green building, he said.

Good Energies, which takes long term investments, has only one investor that it has to answer to, the Brenninkmeijer family, which controls the group through Switzerland based Cofra Holding.

The family also has big real estate holdings, which means all of these green building technologies have a good place to be used.

"Two of our sister companies, Redevco and C&A, which is the Macy's equivalent in Europe—it does retail—have about 75 million square feet, primarily in Europe, some in Asia, some in South America," said Kats. "We're helping them go green, and they're a deployment opportunity for our technologies."

"We're really the only venture capital firm with the real estate deployment capability."

That bodes well for Sage, which has just over 50 employees right now, but Van Dine expects that to go up. "That's the area that will increase the most over the next twelve months."

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