Smart glass offers dynamic lighting and heating possibilities
Most people spend the majority of their time indoors, with one study putting the figure as high as 90 %. But with the majority of commercial and residential windows not allowing in enough natural light, health and wellbeing often suffer. Current solutions, including thermodynamics (TC), electrochromism (EC), polymer-dispersed liquid crystal (PDLC) devices and suspended particle devices (SPD), all have limitations. Only EC has full-range transparency, and other than PDLC all have delayed responses. The EU-supported Intelligent Glass project uses PDLC technology, where a film of liquid crystals is placed within layers of electric conductors. This film is then sandwiched between two glass layers. Specialist glass processing, developed in-house, alongside vacuum and thermo treatment of the PDLC film, enable additional features. These include: full-range dimming transparency; smart tuning; heat protection; energy saving; better UV protection, and usage as a projection screen. “The solution’s functions can be fully integrated into smart buildings and devices. For example, window transparency adjustments can be automatically triggered by heat or light sensors,” explains project coordinator Simon Jenkole from Pametno steklo (website in Slovenian), the project host.
A more dynamic use of space at home and work
The Intelligent Glass solution can be mounted for a variety of uses. It can function as a straightforward window or glass façade but can also work as a divider for offices or homes. It can be installed just like a normal window with its panels’ transparency levels adapting to weather conditions. “This opens up more possibilities for how we can use our spaces, while giving the illusion of either more openness or privacy, depending on need,” notes Jenkole. The system has a full dimmable transparency range of 0-100 %, with UV protection and a response time of under a second. Transparency levels also regulate room temperature, offering more energy efficiency than normal windows. Intelligent Glass can be installed on curved and non-standard surfaces and accommodate additional touchscreen units. In addition to autonomous operation enabled by sensors, Intelligent Glass can be controlled by mobile devices or a manual control panel. The project team integrated the PDLC and electrochromic technology into their sandwich design, which was successfully tested for temperature, transparency and UV protection. Results have shown Intelligent Glass can achieve peak electricity demand savings of up to 30 %, while offering 67 % better heat efficiency. Exposure to natural sunlight was also increased by up to 25 %, representing a real benefit as reduced exposure has been linked to health problems like increased blood pressure, stress and weaker immune systems. These, in turn, can impact on workplace concentration, productivity and energy.
Smarter buildings
Intelligent Glass’s climate-adaptive potential, which saves on heating, air conditioning and lighting costs, is in line with EU policies on heating and cooling. It also supports the Federation of European Heating, Ventilation and Air Conditioning Associations’ ambitions of limiting air conditioning energy consumption in Europe. The team are now fine-tuning the technology to expand its market reach, for example, by further adapting its touch-, projection- and non-standard-surfaces potential. The technology also has to be validated at scale and be able to cater for demands such as different window sizes, thicknesses and electricity standards across countries, before being launched initially in Slovenia and Croatia. “As well as providing a European competitor in this global market, Intelligent Glass could help improve workplace productivity by up to 33 % according to research. It also directly contributes to the drive for smart buildings which are more sustainable and cost-effective,” says Jenkole.
Keywords
Intelligent Glass, glass, lighting, heating, sunlight, UV protection, smart buildings, window, thermodynamics, electrochromism, polymer-dispersed liquid crystal, suspended particle devices, transparency
