FAQ eLstar Dynamics smart glass technology
Although there are some design parameters which influence the switching speed, switching start instantaneous and homogenous: there is no delay. The switching takes in our current design about 30 seconds to go from its darkest state to maximum transparency.
Our switchable smart glass does not share any features with electrochromic devices beyond the fact that both technologies are switchable and use (some) electricity. Our smart glass uses the principle of electrophoresis, or to quote Wikipedia: “the motion of dispersed particles relative to a fluid under the influence of a spatially uniform electric field”.
In plain English: our pigments (the colored parts) are extremely small and are carried by a fluid. By applying a current, these particles are either drawn towards a small electrode, increasing the transparency level or spreading out against the outer pane of the window, darkening the glass.
Switchable glass is glass which can change its tinting state or opacity level. Dynamic glass is another term for switchable glass. Switchable glass can be subdivided into 2 main categories:
- uncontrollable switchable technologies, such as thermochromic and photochromic devices. These technologies change the tinting level based upon temperature (thermochromic) or light intensity (photochromic). The end user cannot chose tinting levels, however there is no power supply required.
- Smart glass or controllable technologies. Smart glass is switched by applying a current (electricity) to the active layer of the product. Smart glass can be transparent liquid crystals (TLC), electrochromic device (EC), polymer-dispersed liquid crystals (PDLC), suspended particle devices (SPC) or electrophoretic. All technologies are different from each other, however they are all controllable by the end user.
No, the switching speed of our dynamic glass does not increase with the size of the glass.
As we work together with existing supply chains across the world, we are facing similar limitations in size as normal glass. We are aiming for sizes 1.5 x 3 meter / roughly 5ft x 10ft.
Our technology is versatile – which includes the colors. We can create any color and also retain this color: from its tinted status until the transparent status, the switching is with the same color. Only the light transmission is altered, not the color point.
First commercial samples will be shipped at the end of the first quarter of 2021. Consumer applications will be available later that year.
Yes, almost any shape possible can be made. We do need to setup exact design boundaries and rules for the maximum bending radius and cross curvatures to allow maximum freedom in (façade) design and engineering.
Anywhere. Our versatility allows us to think broad: from appliance glass to high-end architectural glass. As our technology will be highly affordable, also applications within normal households will be within reach.
Additionally, the use within the transport sector is very interesting: trains, buses and cars are all applications where glare and direct sunlight exposure decrease comfort levels and increase fuel consumption.
Yes – both to change tint levels and to maintain tint levels. The power used is minimal though.
By applying a current to the active layer of the glass. This can be done through function integration with a smart house concept, by connecting through an app or through a regular switch like sunblinds.
During a power outage, the glass will slowly transition to its non-powered status, which is its tinted status. This takes approximately 30 minutes.
The SHGC is depending on many factors and is mainly influenced by the build up of the entire stack of products: is there a low-E coating applied, is it double or triple glazing, what is the thickness of the glass, etcetera. This in turn is depending on the climate zone and other choices which you make during design of the façade and the rest of the building.
However, a part of the infrared light is reflected by our smart glass. In the visible spectrum, as we absorb the light, physics tell us that the substrate becomes warmer. This heat is dissipated from the window by radiation (both inwards and outwards), convection and conduction. In its fully tinted status, the glass heats up the most. The energy which would otherwise heat your body or the inside of the building is absorbed. As there is radiation and convection to the outside, there is less heat gain than through transparent glass. The exact amount however is design dependent.
Yes. First of all, the pigments used do not show any bleaching or other degradation due to UV-light exposure. Secondly, the surrounding glass in the final field of application filters out most UV-light so most UV-light never reaches our application. Thirdly, additional layers of UV and IR radiation might be provided by the IGU maker in the form of a low-E coating or similar. In automotive applications, additional PVB’s are used to absorb all UV.