Soladigm raises $55M for smart windows

Updated: Soladigm, a startup that makes windows that can be tinted on demand, has raised another $55 million, bringing the company’s total funding to $125 million. Soladigm’s investors include DBL Investors, GE, Khosla Ventures, Navitas Capital, Sigma Partners, and The Westly Group.
Soladigm has been building a $130 million window factory in Mississippi, which was supposed to start shipping windows in the first quarter of 2012. It’s unclear if the company has started shipping its windows yet, but I’ll update this if I hear more from them. I would speculate that this funding will go toward helping the company move into commercial production. Update: A Soladigm spokesperson says the company hasn’t begun commercial production out of the Mississippi plant yet, but is on track to do so later this year.
Founded in 2007 and based in Milpitas, Calif., Soladigm makes electrochromic windows, which change colors to reflect or absorb light when a low-voltage electrical current is applied. The tinting effect can cool or warm a room, and save energy by cutting down on air conditioning. The Department of Energy has noted that electrochromic windows can cut a commercial building’s air conditioning costs by up to 20 percent per year.
The company uses a thin-film deposition process to create conducting layers between two panes of glass for controlling the amount of light and heat that pass through. The secret sauce to the window is the materials used to make the electrochromic layer. Soladigm is using a tungsten oxide-based electrochromic layer for its initial product. Soladigm has licensed technology from Lawrence Berkeley National Laboratory.
The big challenge for popularizing electrochromic windows is cost. Electrochromic windows can fetch around $100 per square foot, while windows with reflective coating already are widely available and cost far less. Soladigm has declined to disclose its manufacturing costs.
Soladigm competitor Sage Electrochromics, was acquired by French glass and construction giant Saint-Gobain earlier this year. Saint-Gobain had long been an investor in Sage.