Glass has a rich and storied history dating back thousands of years. From creating iconic, color-splashed panels for cathedral interiors to wrapping modern office towers in massive glimmering panes of glass, the material has always been a way to make a striking architectural statement.
As glass making techniques have improved over the centuries, functional improvements followed. Better technology made it possible to produce glass that provided better insulation and offered higher durability even with enormous panes. But that’s nothing compared to the innovations glass offers today. What modern glass is capable of is more like something you’d expect to see on the Starship Enterprise than a Cape Cod house in the suburbs.
Just one example is so-called smart or dynamic windows that can turn from dark to completely transparent in less than a minute. These windows not only shade your eyes from the sun, but can lower the energy costs of a building by up to 20%, according to Live Science. Stanford University researchers developed these electrochromic windows, which use “a polymer gel containing metal ions applied on top of a transparent electrode,” Live Science described. Depending on what voltage is applied, the windows change between opaque and transparent.
The technology for now is mostly used in luxury car and airplane windows, but Michael McGehee, a Stanford University materials science and engineering professor, told Live Science the potential applications for construction could be widespread once the cost is brought down.
“They can be used in windows of all kinds of buildings, homes, larger commercial buildings,” he said.
The window settings can even be fine-tuned to be partially transparent, allowing occupants to see outside without letting people outside see in.
“You can block 90 percent of the light to reduce the glare, but you can see what’s out there… It’s not like if you have blinds or in an airplane — when you pull the plastic down, then your view is completely gone.”
Since sunlight relentlessly beats down on windows all day long, it makes a perfect receptacle for collecting the sun’s energy in the form of usable electricity. The advent of solar windows enable buildings to do just that, and researchers are actively working to perfect the technology. The tricky part is finding the balance between keeping the windows properly transparent, but without sacrificing the quality of the energy gathering solar cells. So far, that Goldilocks zone has eluded the scientists, and mainstream adoption of fully transparent windows that efficiently collect solar energy isn’t quite there yet.
However, several companies are selling workaround solutions, according to Business.com. Like Brite Solar, whose Solar Glass uses alternating panels of transparent and partially transparent glass embedded with photovoltaic solar cells, creating the illusion of total transparency. So far Solar Glass is predominantly used in the agriculture industry.
Ubiquitous Energy’s ClearView Power is a nearly-transparent solar coating currently in development. It’s a film less than one-thousandth of an inch thick that’s designed to be applied to any surface to transform it into a solar panel without changing its appearance. According to Business.com, the team’s best effort so far is achieving 90% transparency with 10% solar collecting efficiency.
Even beyond solar, University of Exeter Renewable Energy experts have launched a startup called Build Solar to produce and sell its innovative glass block solar radiation collectors, that can be incorporated into a building without the need for traditional solar panels. According to Phys.org, the blocks can be built into an initial design or retrofitted to an existing structure, just as glass blocks often replace sections of masonry to let the sunlight in. Each block contains intelligent optics that focus the energy they collect from the sun. The energy is stored and becomes available as usable energy. It’s a huge step towards zero-emission buildings.
Professor Tapas Mallick, chief scientific advisor for Build Solar, told Phys.org, “We are aiming to build integrated, affordable, efficient and attractive solar technologies, which have the smallest impact on the local landscape. It’s an exciting venture and one that should capture the imagination of the construction industry.”
The future of glass technology could pave the way to the kind of glass-encased sparkling megacities of science fiction and fantasy, but as is the case with many other nascent technologies, the cost has to come down to earth before widespread adoption can ever be possible.