Development of new solar shading systems based on daylight-directing solar control glass lamellas

To reduce electricity consumption for cooling and ventilation in buildings with glass facades, it is necessary to use efficient solar shadings. At the same time it is necessary to optimise the utilisation of daylight to meet stricter requirements for a daylight factor of at least 2 % at work places and also to reduce the electricity consumption for artificial lightning. In buildings with large room depth in relation to windows, there is often ample daylight close to the windows and too little at the back of the room. Therefore new efficient solar shading devices should be developed that can reduce solar gain in the surroundings close to windows. At the same time they should direct part of the solar light further into the room.

The aim of the project is to survey the energy saving potential and daylight conditions for the new types of flexible solar shading devices consisting of glass lamellas with solar control coatings with high reflectance that can shade for direct solar radiation and at the same time direct the daylight further into the room where it is most needed.

The project will result in a new type of solar shading that both solves the problem of high temperatures as a result of too high a solar gain and at the same time optimises the exploitation of daylight so that energy consumption for lighting is minimised. The new solar shading system can be used in new as well as existing buildings and will result in a significant reduction of the electricity consumed for cooling, ventilation and artificial lighting. An added benefit of the new system is that it will reduce the heat loss from facades during winter and solve the problem of exterior condensation on low-E glazing. The new solar shading system can be used directly by manufacturers of solar shading either in the production or for further development.

The project is Subsidised by ELFOR, PSO F&U 2006.