When you look at your window, what do you think about? Nothing crosses your mind about it generating energy, right? But what if that idea were about to change forever? Yes, we’re in a new era: that of smart glass. What does that mean? Well, transparency no longer represents passivity, and the light that passes through also provides energy. And this technology is closer than ever, as the US is preparing to receive its first energy-generating window. This innovation could revolutionise the field of architecture, urban energy, and even the way we interact with everyday electronics.
How can your window generate energy?
Have you ever thought that a window could generate energy? Well, that’s the idea that led researchers at UNIST in South Korea to create something impressive: a flexible, transparent, and, surprisingly, completely colorless solar cell. The secret lies in so-called silicon microscopic wires (SiMWs), embedded in a layer of transparent silicone. But how does it work? These wires are positioned far enough apart to let light pass through, maintaining the appearance of glass. At the same time, they are close enough to capture solar energy and transform it into electricity.
These microwires act as a veritable invisible capture web. In other words, light passing through the free spaces continues to illuminate the environment, but some of the light that reaches the wires is absorbed and converted into energy. And it doesn’t stop there: the researchers went further and redesigned the ends of the wires to be angled, allowing the light reflected from one wire to be redirected to the next, creating an absorption cycle that further enhances efficiency.
A transparent and bendable solar panel in your window
Of course, this technology has faced some challenges. One of the biggest criticisms of transparent solar cells has always been their undesirable coloration. This is because they could be bluish, yellowish, opaque, and often very fragile. Until this South Korean innovation arrived to deliver a clean, neutral look without color distortion (it looks like a translucent solar panel in your home).
Another notable feature is that the solar film is thin, flexible, and resistant to bending. What does this mean? It can be applied not only to buildings, but also to automotive glass, wearable devices, foldable screens, and even movable facades, such as awnings or adjustable partitions. And no, performance doesn’t decline even with a 6mm radius of curvature, which is extremely rare for solar panels. And last but not least, the structure is stretchable. This means that if tension is applied, transparency can be increased or decreased. With all this, you’ll have a window that, with a simple command, can darken slightly for privacy while still generating energy.
“The new solar cell is expected to maintain its initial efficiency of more than 95% and be applied to a variety of buildings, vehicle glass, and portable electronic devices”, said Professor Kyoung Jin Choi, from UNIST.
Does this power-generating window change that much?
This type of window offers a crucial advantage. Do you know what it is? We live in a world where every square meter counts, especially in cities, generating energy without sacrificing usable space has become an obsession. It’s impossible not to say that solar panels on roofs have helped, but they still leave areas like facades and windows as mere spectators.
Now, your window glass itself can become a mini-power plant, without obstructing the view or compromising the building’s design. And best of all, without requiring complex maintenance or additional surfaces. In terms of efficiency, the cell reaches 8.07% with 10% transparency. Now, imagine what you could achieve if you could combine these windows with this 5,550 kWh-per-year domestic wind turbine…
