AGC Glass Europe

Energy consumption has been a source of growing concern over the past few decades, and limiting heat losses through glazing has become a priority for glassmakers. AGC Glass Europe and its R&D Centre have long worked on improving the insulating properties of glass by applying coatings on it. This is an advanced glass technology for which AGC Glass Europe claims European leadership.
AGC Glass Europe boasts a wide range of superinsulating coated glass, also called low-emissivity (low-E) glass. These include the recently developed Thermobel Energy N^® with a Ug value (indicating the level of heat loss) of only 1.1 W/(m².K). This double glazing offers excellent insulating properties, as the heat loss is completely cancelled out: the quantity of heat entering the building through solar gain is higher than the heat leaving the building through the window. The overall balance becomes positive, i.e. the solar gain is larger than the heat loss. In this way the windows actually contribute to the heating of the house, leading to energy savings that correspond to about 6 kg of CO₂ per square metre per year, or 120 kg of CO₂ per dwelling per year.

By contrast, single glazing has a Ug value of 5.8 W/(m².K). In such a case more heat is lost through the window compared with solar gain: the overall balance is a clear loss of energy. This loss of energy must be compensated by extra heating corresponding to emission of 84 kg of CO₂ per year per square metre of glass, or 2,000 kg of CO₂ per dwelling per year.
The use of ordinary double glazing with a Ug value of 2.8 improves the balance by reducing the amount of heating needed, but it remains still negative with an overall energy loss corresponding to 22 kg of CO₂ per square metre of glass, of 500 kg per dwelling per year.
Now if we compare on the one hand the energy used and the CO₂ emitted to produce the glass, and on the other the energy and the CO₂ saved by using low-E double glazing, the balance is once again positive. To produce 1 square metre of   Thermobel Energy N^®  , the industry emits around 25 kg of CO₂. By contrast, replacing single glazing by low-E double glazing leads to a saving of about 91 kg per year. That means that the CO₂ emitted to produce the glazing is offset by the savings in 3.5 months. If conventional double glazing is replaced by Thermobel Energy N^® low-E double glazing the time needed to cancel out the CO₂ emission is 10.5 months.

 

For more information see http://www.glassforeurope.com/images/cont/166_43490_file.pdf

Since Energy N®, AGC has developed a wide range of coated glass such as  Top N+ , Top 1.0, Stopray 0.9 and Stopray Ultravision   that have higher performance than Energy N®.
For example, by combining soft and hard coatings AGC offers a whole range of Stopray products with a Ug value of 0.9. This combination of Stopray coating and Planibel G Fast significantly enhances the thermal performance of the insulating glass.

The new  Stopray Ultravision 50  is a high performance soft-coated glazing with an innovative triple silver coating. Light transmission is maximised (LT=49%) while solar heating is significantly reduced (Solar Factor 23%). Stopray Ultravision 50 makes it possible to benefit from more interior light and lower cooling costs.

AGC has also developed a large range of double glazing products using these coatings, such as Innovation Structura Duo+ and Thermobel VIP (Vacuum Insulation Panel).

Structura Duo+
AGC produces insulating double glazing system recommended when a high level of thermal and solar performance is required. Stopsol, Sunergy or Stopray solar control glass can be used in Thermobel glazing. Structura Duo combines the light and aesthetic properties of structural glazing with the performance of insulating glazing. Structura Duo+ features new composite materials to replace the aluminium surround, thus improving insulation and enhancing the appearance of the installed system. This solution is especially suited to facades with double glazing, laminated glass or monolithic glass for use in northern European climates.

Thermobel VIP (Vacuum Insulation Panel)

Thermobel VIP is the latest innovation in terms of fully insulated glass facades. Used as a spandrel, Thermobel VIP is double glazing combined with a vacuum element which allows optimal thermal insulation of all-glass facades, with Ug values of up to 0.15 .  
Thermobel VIP can be totally recycled and can also provide sound insulation.

 

Thermobel TRI is a new type of triple glazing specially developed by AGC. The objective was a product with high environmental performance while letting as much natural light as possible to enter buildings (the main disadvantage of standard triple glazing is that it is rather dark). As well as a very low Ug value, Thermobel TRI offers a higher level of light transmission than other products on the market, and, most importantly, a higher solar factor. This maximises free solar gains, meaning you can use the sun’s energy to heat your home. Thanks to these unique properties, Thermobel TRI easily meets the criteria for passive home heating, delivering a Ug value of 0.7 W/(m².K) and a solar factor of up to 63%.

One for the future

Based on a study of the ift Rosenheim ni Germany, a window fitted with triple glazing with a high solar factor, such as Tri, is optimal for the residential market. Compared to similar products on the market, it offers the highest energy savings, which can decrease the annual energy consumption by up to 10%? Considering the variation in energy prices and the window's durability, it's a good investment.

Recently, three important studies*, commissioned either by AGC Glass Europe and/or Glass for Europe, showed the energy efficiency performance of the new TRI coating. The results of those three studies match and confirm the added value of the TRI coating.
 

Read or download the studies on www.agc-tri.com or see the webcast on http://webcast.yourglass.com/tri/
 

Moreover, installing triple glazing with TRI not only cuts energy consumption but also adds value to the building, bearing in mind the new legal requirements for energy certification of residential buildings.

^*Study 1: IFT (Institut für Fenstertechnik) – Institute for Window Technology. “Study of energy conservation and thermal insulation of high-performance triple insulating glass units with optimised solar energy transmittance. Calculation for residential buildings.”
Study 2: TRIBU – French Institute in Environment for the building and town planning sectors in France. “Study on the impact of glass in an environment statement for an individual house in France.”
Study 3: TNO – Institute for market research and scientific research in the Netherlands.

Among human activities, transport and more particularly car use is one of the major sources of CO₂ emissions nowadays. At the same time, emerging and fast growing economies are contributing strongly to the increase in car sales. The best example is China where car sales are growing by approximately 25% a year.
In industrialised countries (Europe and the USA) there is a strong willingness to reduce the contribution to CO₂ emissions made by transport. Indeed, governments are introducing new regulations targeted at cars, and fines are also planned for car manufacturers who fail to reach their targets. Car manufacturers are under heavy pressure to lower the fuel consumption of their products, and are responding by improving engine efficiency, aerodynamic design, using lighter materials etc. At the same time, glass is much in demand by car manufacturers because of its excellent properties (mechanical, optical etc.), its aesthetic qualities and the great visibility it affords. The glass area used in cars is continually increasing, a feature that is sometimes even used as a marketing advantage. Accordingly, glass manufacturers have a responsibility to provide innovative solutions in order to contribute to the reduction in CO₂ emissions.

CO₂ emissions are directly correlated with fuel consumption of the car, and there are basically two ways to reduce this by using glass. The first is to decrease the weight of the glass. For example, if the thickness of the windshield is reduced by 0.5 mm or so, CO₂ emissions are lowered by approximately 0.2 g/km. By decreasing the thickness of all the glazing, CO₂ emissions can be reduced by about 0.5 g/km.
The second way is to improve the thermal properties of the glazing. Given that air conditioning can increase fuel consumption by 10%, improving the thermal isolation will reduce the fuel consumption.

The sun’s spectrum is made up of thee kinds of radiation: ultraviolet, visible and infrared. In an ordinary windshield, the ultraviolet is absorbed by the polyvinyl butyral interlayer but the visible and infrared radiation is mainly transmitted through the glass. The visible and infrared ranges are responsible for 54% and 43% respectively of the energy transferred into the car. One of the major functions of the windshield is of course to provide high visibility for the driver, and therefore regulations impose a minimum visible light transmission of 70%. The problem is as follows: how to significantly reduce the energy transmission through the windshield while maintaining sufficient transmission of visible light? The IRIS® coating developed by AGC provides an answer to this question.

The IRIS® coating is a complex stack of different thin metallic coatings, deposited directly on clear glass by the magnetron sputtering process. It is important to note that magnetron sputtering only generates wastes that can be recycled. Furthermore it is a dry process and consequently environmental friendly. After coating, the glass can be curved and laminated in conventional windshield production lines.

The IRIS® windshield provides high visible light transmission (more than 70%) and high infrared reflection. These unique properties permit energy reflection of about 35% compared with 5% for a conventional windshield. The total energy entering the car is decreased by 10% compared with the best absorption technologies in which part of the energy absorbed inside the windshield is re-emitted into the car. This technology decreases the thermal load inside the vehicle and consequently the need to use air conditioning for cooling the interior. Based on simulations by AGC and our customers, the IRIS® windshield is estimated to decrease CO₂ emissions by 1 g/km.
Comfort is also improved for the driver and passengers. Our simulations show that the temperature of the dashboard and seats can be lowered by 9°C, making them less hot to the touch. This further reduces the use of airco.

Given the total amount of CO₂ emissions in Europe generated by transport*, reducing the CO₂ emissions for each vehicle by 1.5 g/km would cut annual CO₂ emissions in Europe by 6 million tonnes!
Beyond this impressive statement, AGC considers that this kind of product has a bright future, especially for the new electric vehicles for which the challenge will no longer be CO₂ emissions but the power savings necessary to achieve a sufficient driving range.