Glass is also chameleon

2000/03/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Ingeniaritza

A bank of the German city of Dresden has for the first time used glass windows that vary their transparency depending on the light intensity.

The tests have revealed that this material saves 50% of the energy needed for the air conditioning of buildings. The thin layer of tungsten oxide is attached to the surface of the glass and the low-intensity electric current passing through it changes the color of the membrane. Thus, transparent glass becomes blue. When the intensity of light coming from the street is very high, the glass loses transparency and the maintenance of the cool building requires less air conditioning, so energy is saved.

On the contrary, when the light intensity decreases, the glass recovers initial transparency and the need for artificial light decreases. In addition, the transparency of the glass can be controlled centrally in the windows throughout the building.