Gases for Life - Messer Group

Green PageEnjoying the optimum insulation properties of insulated glass: Messer employees Ute Schaad, Marlen Schäfer and Anita Kötél.Krypton optimises insulation performance of insulated glass windowsBenefits of gas in glassHeat insulation is one of the most important “alternative energy sources” with the potential tomake a major contribution to climate protection. Windows are the main culprits when it comes toenergy leakage from buildings. The use of noble gases such as krypton can significantly improvethe insulation performance of insulated glass.It is a basic law of physics that wheredifferent temperatures meet, theyseek to balance each other out. Evermore sophisticated insulation techniquesare being used in buildings to preventthis ‘balancing out’ in order to saveheat energy. Of course, the quality ofthe glass and the finishing is crucial indetermining the insulation propertiesof double or triple-glazed windows. Butwhat you put in the space between thepanes also plays an important role in thisregard: the lower the thermal conductivityof the filling gas between the panes,the better the insulation.The simplest filling gas is air, but it hasrelatively high thermal conductivity. Thenoble gases argon and, in particular,krypton, which is rarer and thereforemore expensive, have lower thermalconductivity.The superior insulation properties ofkrypton allow the gap between theindividual panes to be reduced comparedwith conventional insulated glass windows.Thus for argon, the optimal gapbetween panes is 16 mm, while for kryptonit is only 8 to 12 mm. This enablesthe U-value to be reduced by between0.3 and 0.5, depending on the filling gasand filling level. Double-glazed windowsfilled with krypton can thus achieveinsulation values that are comparablewith those of much heavier, argon-filledtriple-glazed windows. Furthermore,windows filled with noble gases havethe welcome side effect of also offeringimproved sound insulation.Jens Tauchmann, Messer GroupThe U-ValueInsulation efficiency is expressed with the U-value, which indicates how much heat a buildingmaterial allows to pass through. The lower theU-value, the greater the insulation. For example,a single pane of glass has a U-value of 5.8,while insulated glass filled with air has a U-valueof 3.0. If argon is used as a filling gas, U-valuesof under 1.5 are achievable, while the use ofkrypton allows this figure to be reduced evenfurther to below 1.0.3.02.52.01.51.00.5GlassAirArgonKryptonGases for Life 03 | 201117