Insulated Glass is a very prominent building material today, and with the high volume of insulated glass units being used, it inherently plays a significant role in both energy consumption and energy savings. Heating and cooling a building requires a lot of energy, so anything that can be done to reduce the amount of energy needed or conserve the energy already expended will result in less CO2 emissions and less cost.
One of the best energy conservation measures that can be implemented for today’s buildings is to use modern insulated glass equipment to produce high efficiency, energy-saving double-glazed, triple-glazed or vacuum insulated glass units (known as VIG units). The vast majority of the buildings standing today were built when energy conservation was not as important as it is today. These buildings consume a large amount of energy for heating and cooling. The windows used in many of those buildings are double glazed, as this technology has been around for decades, but compared to today, they are extremely inefficient at conserving energy. Insulated glass units started being used after the first series of petroleum crises were experienced in the US, which did help energy savings to a small degree, but the insulated glass equipment of the day simply doesn’t compare to what we can do today. Thus, even those older insulated glass units are now completely outdated.
Using advanced glazing solutions will significantly reduce heating and cooling consumption and dramatically reduce the associated CO2 emissions. These advanced solutions include Low-Emissivity (Low E) glass, which is glass treated with a special transparent coating. This coating.
reflects or absorbs heat (in the form of IR light or heat energy). In cold weather, this coating can reflect heat back into the building reducing energy loss from the window, as well as absorb solar energy from the outside. In warm weather, this coating reflects heat from the outside, not allowing it into the building, and thus, reducing cooling costs and energy consumption. This coating is expected to remain an important aspect of the glass industry well into the future.
Today, this specially coated glass is also being used in conjunction with various gases, including argon and krypton, to further reduce loss in double glazed and triple glazed insulated glass units. These gases are safe, odorless and non-toxic. The gases work to conserve energy because they are much denser than air, and thus, provide considerably more insulation value, which significantly reduces heat transfer. Adding these gases to insulated glass units is done most efficiently by today’s advanced insulated glass equipment and manufacturing techniques.
A new type of insulated glass panel that is growing in popularity is Vacuum Insulated Glass units (or VIG units). Many glass industry experts believe these vacuum insulated glass units are the ultimate solution for energy conservation in windows. The special insulated glass equipment required to produce these vacuum insulated glass units represents a major capital investment, in the tens of millions of dollars, but many glass industry experts feel it is worth the expense, as this glass will become the industry standard in the future.
To understand how vacuum insulated glass panels work, think of a ThermosR brand container used to keep drinks hot or cold for 8 hours or so. These containers are called vacuum flasks. They are double-walled and the air molecules have been almost entirely removed from the area between the walls. This lack of air, or vacuum, dramatically slows conductive and convected heat flow. This same principle is applied to vacuum insulated glass units. When this technology is combined with the specially coated Low E glass, the benefits of vacuum insulated glass units becomes even more dramatic. In the near future, heating and cooling energy consumption could be reduced to the point where these windows are rated R-12, the same R-value achieved with a traditional 2” x 4” studded wall.
This tremendous potential energy conservation from windows will be made possible by advances in insulated glass equipment, which allows these new insulated glass units and vacuum insulated glass units to be produced cost efficiently and with the highest quality.