How Solar Gard® window film saves energy
In ¼” (3mm) annealed glass, 87% of the energy is transmitted, 5% is absorbed and 8% is reflected.
Solar Gard window film reflects significant solar energy, while absorbing another portion of the energy. The result is that the amount of solar radiation transmitted inside the room is considerably less. Specs will vary depending on the Solar Gard window film selected.
The movement or transfer of heat from a region of higher temperature to one of cooler temperature is called heat transfer. The transfer of heat always flows from hot to cold. No heat will transfer if there is no difference in temperature.
There are three types of heat transfer: Radiation, Conduction, and Convection. For window film, radiation is the most important method of heat transfer because it moves infrared waves. This is why we refer to solar energy as solar radiation.
Solar energy through a window is transferred or transmitted by infrared waves. Radiant energy is converted to heat when it strikes people or objects. If you block the transfer of this energy you keep it from turning into heat because it never strikes an object. Window film interrupts the transfer of this energy by reflecting the energy back.
Transmission is basically the percentage of Solar energy (UV + Visible Light + Near Infrared) that can passes through a window. Reflection is the ratio of solar energy reflected back to the source, expressed as a percentage. Absorption is the percentage of solar energy absorbed to that of the total solar energy.
With solar window film installed on the inside of a window, the proportions are changed dramatically, with reflected energy and absorption increasing. This corresponds to a reduction in solar heat transmitted inside the room or the automobile. The properties of the window film dramatically influence how and in what way transmission, reflection and absorption change.
