Energy Efficient Windows

Energy saving windows (Facade) 

Energy efficient windows

The offices in the building with lots of glass windows provide a great view for the employers but from energy efficiency point of view it is not economical. This is because of the sunlight that pours into the office thus results in raising the inside office temperatures and leads to operate the air conditioning for cooling.  The Fraunhofer Institute for Machine Tools and Forming Technology in Germany has done a research on this issue and able to create a light blocking facade on mirrors that will not allow light to enter into office. The facade was developed in coordination of Fraunhofer with Weissensee School of Art in Berlin.  

It was designed by one of a student named Bára Finnsdottir. The façade was an array of circular shaped small umbrellas made of a fabric type material with wires running through them. Such wires are made up of an alloy of nickel- titanium. When sunlight strikes on these umbrellas the wires heated up and allow the circular shaped umbrellas opened up till the sunlight disappears. Such façade has the characteristics of open and close according to intensity of light. So the façade become translucent as sunlight disappears or the clouds came in thus allowing the circular discs to be shut down.

Such kind of façade can be easily retrofit on surface of glass windows and also within the pane in case of double door windows. The façade can be designed in different shapes and sizes and can only be used to cover the desired area of a window.      

      

More research is going on in making façade of such kind of material that will absorb such thermal energy and release it during night in order to generate electricity from it or by using flexible solar cells in front of windows as a facade that will withstand such closing and opening position.

The demonstration of that technology as a working prototype will be shown on 13 to 17 April 2015 at a industrial trade show of Hannover Messe.