Smart glass that can tint automatically has recently been featured on a crop of highly visible new buildings, like Levi’s Stadium and Overstock’s Utah headquarters.

Can that increased demand help a cleantech manufacturing startup navigate a difficult, risk-averse market? Investors don’t seem to be shying away. 

On Tuesday, View Dynamic Glass announced that it had raised another round of $200 million, with $70 million coming from funds and accounts managed by BlackRock, and $50 million from the investors at TIAA Investments. The company said existing investors participated in the round, but declined to specify which ones. 

The round brings View’s total funding to over $700 million -- a lot of funding for a tech startup that isn’t a well-known Silicon Valley darling. View has fixed manufacturing costs and a factory that churns out its glass in Mississippi.

Previously View raised $150 million from a fund set up by the New Zealand government for citizens’ retirement costs; glassmaker Corning; and Madrone Capital Partners, a fund associated with the Walton family, heirs to the Walmart fortune. Prior venture capital investors include Khosla Ventures, DBL Investors and The Westly Group. 

CEO Rao Mulpuri described the funding round as validation of View’s growth, and said the money would be spent on adding production capacity at the Mississippi factory. “We’re growing 25 percent every quarter” and doubling glass output every year, said Mulpuri. 

To date, View has installed its smart glass at 350 corporate offices, airports, hospitals, stadiums and universities -- adding up to a total of 20 million square feet.

The electrochromic technology came out of Lawrence Berkeley National Lab. It uses a thin layer of tungsten oxide deposited onto a pane of glass and sandwiched by another pane of glass. When voltage is applied, the windows can tint on demand. 

Electrochromic windows can cost twice as much as a standard double-paned window. But the energy savings from keeping buildings cool by tinting the windows can be pretty substantial. Tinting can cut 20 percent of a building’s heating and cooling costs and 20 percent of lighting costs.

But most of View’s customers are not buying the windows solely for sustainability or cost-cutting. Many of them buy the windows because they’re a cool tech product.

View’s windows automatically tint and un-tint depending on the position of the sun, or based on workers' preferences. Unlike with blinds, employees can enjoy views and natural light, even when the sun is glaring down on the building.

Mulpuri said View's project sizes are growing, and that the company is “production-limited rather than demand-limited.” In addition to those 350 buildings in its portfolio of completed projects, View has another 150 buildings waiting to get windows. 

Despite the recent strong growth, it's taken a lot of capital to reach this point.

Many other cleantech manufacturers that have raised similar amounts of money have struggled, or have gone bankrupt. Raising $750 million doesn't guarantee success -- in most cases, it's been a predictor of future problems.

View isn't saying how much production it plans to add to its Mississippi factory. Mulpuri confirmed that View isn’t yet operating at the 5 million square feet per year it once set as a factory goal.

But he said that the company is now in a phase of “wash, rinse, repeat” (meaning the product has been refined considerably), and it is now focused on growth.

View is one of a handful of cleantech startups that worked with the state of Mississippi to get factories built (many under the aegis of former Governor Haley Barbour), and is one of the few companies still operating in the state. Biofuel disaster KiOR is the most well-known flame-out among the list of companies.

View isn’t the only maker of smart glass out there. French glass giant Saint-Gobain acquired Sage Electrochromics in 2012.