Case Studies

Understanding how the Solar Spectrum is measured

The sun radiates solar energy via electromagnetic waves over a range of wavelengths known as the Solar Spectrum (280 - 2500 nanometres: 1 nanometre = 1/1,000,000,000 of 1 metre)

The Solar Spectrum is commonly divided into three bands (based on ISO9050):

Ultra-violet (UV)280nm - 380nm

Visible Light (VL)380nm - 780nm

Infra-red light (IR)780nm - 2500nm

The energy distribution within the Solar Spectrum is approximately:

2%Ultra-violet

47%Visible light

51%Infra-red light

It is important to understand that the shorter the wavelength (ie the lower the nanometers), the higher level of energy associated with the radiation. This is highlighted by the fact that it is the shorter wavelength, high energy UV light which causes skin to burn, fabrics to fade and plastic to deteriorate.

RAT Equation (Reflect, Absorb, Transmit)

When combined solar energy hits glass - Ultra-violet, Visible Light and Infrared rays - it is reflected (by glass to the outside of a building), absorbed (by the glass) and transmitted (through the glass into the building) in different proportions (depending the type of glass involved).
Example:
6mm clear float glass reflects 6.9%, absorbs 15.2%, and transmits (directly) 77.9% of solar energy. With KristalBond applied to 6mm clear float glass it now: reflects 5.7%, absorbs 51.5% and transmits 42.8% of solar energy.

This means that with KristalBond on your glass, it is now reflecting 1.2% less, absorbing 36.3% more and transmitting 35.1% less solar radiation into your building.

Another very important measurement is the U-value. The U-value measures how well heat flows through an object (its thermal conductivity) ie.The rate of heat loss or gain through glass, due to the environmental differences between outdoor air and indoor air. The lower the U-value, the better the insulation offered.
6mm float glass has a U-rate of 5.83 and KristalBond rates at a far lower 3.46

The most important measure however, is how much UV light is flowing into your home or office. Remember, UV light not only causes skin to burn, but also causes fabrics and fittings in homes, offices and retail premises to fade and/or deteriorate over time, which is an unnecessary and costly exercise. Untreated 6mm float glass allows 59.2% UV light into your environment

With KristalBond applied, an amazing 0% now enters the premises ie no UV light is transmitted through KristalBond.

Performance

KristalBond BG 90 Spectral Performance Data

Tested based on ISO 9050 standard, except U-Value which is based on ISO 8990.
SHGC - Solar Heat Gain Coefficient, Ref - reflectance, Trans - transmittance, UV - ultra violet, Abs – absorptance

What Cause Color To Fade?

40% Ultraviolet 25% Light 25% Heat 10% Others

There is more than one factor that cause colour to fade. Of all the factors including heat, light and external conditions, UV light is by far the most detrimental.

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