Dynamic windows have long been a promising solution for achieving energy efficiency in buildings. These windows, which can change their opacity in response to electric stimulus, offer the possibility of controlling glare, blocking infrared light, and maintaining a clear view. However, until now, most dynamic windows were limited to only two states: completely transparent or completely dark.
In a recent study published in the journal ACS Photonics, researchers have demonstrated a breakthrough in dynamic window technology that introduces a new material capable of three distinct modes. This material, based on hydrous tungsten oxide, offers the ability to switch between transparent windows, windows that block infrared light, and tinted windows that control glare. With this advancement, building occupants will have more options for maintaining a comfortable indoor environment while reducing energy consumption.
The key to achieving these three modes lies in the presence of water within the crystalline structure of tungsten oxide, forming what is known as tungsten oxide hydrate. Previous dynamic window materials were limited in their functionality because they lacked this critical water component. By introducing water, researchers have discovered a previously unknown behavior in the material.
By injecting lithium ions and electrons into the tungsten oxide hydrate material, the researchers were able to tune the wavelengths of light that are blocked. This process results in two distinct modes: the “cool” mode and the “dark” mode. In the cool mode, the material allows visible wavelengths of light to pass through while effectively blocking infrared light. This mode helps keep buildings cool, thus improving energy efficiency.
In the dark mode, the material transitions to block both visible and infrared wavelengths of light, providing complete opacity. This mode offers effective glare control while maintaining privacy. The ability to switch between these two modes provides building occupants with greater flexibility in managing the amount of light entering the space.
The presence of water in the crystalline structure of tungsten oxide hydrate plays a crucial role in the material’s behavior. Because water makes the structure less dense, it becomes more resistant to deformation when lithium ions and electrons are injected into the material. This increased resistance allows the material to accommodate more lithium ions before undergoing structural changes.
The discovery of dual-band light control in a single material, already known to the smart windows community, holds great promise for accelerating the development of commercial products with enhanced features. The ability to switch between multiple modes gives manufacturers the opportunity to create dynamic windows that cater to the specific needs of building occupants.
By offering windows that can be transparent, block infrared light, and control glare, these advancements in dynamic window technology contribute to creating more sustainable and energy-efficient buildings. The reduction in energy consumption achieved through the use of these windows could have a significant impact on overall energy efficiency and, consequently, on the global environment.
The latest breakthrough in dynamic window technology provides a great leap forward in achieving energy efficiency in buildings. By utilizing hydrous tungsten oxide, researchers have introduced a material that allows for three distinct modes: transparent, infrared-blocking, and tinted windows. With the ability to switch between these modes, building occupants can enjoy a comfortable indoor environment while reducing energy consumption. This discovery holds immense potential for commercialization, driving the development of enhanced dynamic window products that cater to the specific needs of different buildings and occupants. As we continue to prioritize sustainability, advancements in dynamic windows like these are crucial steps towards a greener future.