The Hohenstein Institute in Boennigheim, Germany, has expanded its current range of tests to allow modern office and living spaces to achieve  needed climate control with minimum energy use.

According to the institute, manufacturers of textiles, windows and multilayer glass as well as other transparent materials, such as films, will be able to use the test results to optimise their products specifically with regard to low energy transmission.

Energy saving

Based on EN 410 ‘Glass in building’, the experts at the international research and test institute determine the so called g-value as a measure for the energy transmittance of materials.

The energy savings resulting from a low g-value, as well as comfort aspects and consumer safety are becoming increasingly important for marketing products, the Institute reports.

Low g-value = high energy savings

The g-value is composed of the directly transmitted solar radiation and the secondary heat emission resulting from radiant emittance and convection on the inside of the material.

A g-value of 1 corresponds to an energy transmission (heat gain) of 100%. Conventional uncoated glass has a g-value of about 0.85, which means that 85% of the incoming heat can be transmitted into the room behind the glazing. The rest is reflected or absorbed by the glass. Modern triple glazing has a value of approximately 0.55.

Waves transmission

With the measurements using modern spectral photometers, the experts at the Hohenstein Institute cover the wavelength range from 250 to 2500 nm, such as UV radiation, visible light as well as infrared heat radiation.

According to the Institute, tests can also provide information about direct radiation transmittance, radiation reflectance, radiation absorption factor, light transmittance, light reflectance as well as UVA and UVB transmission.

www.hohenstein.com