How Solar Energy is Distributed
Solar radiation emitted from the sun was lost through many barriers as it enters through the atmosphere. 29% has reflected to space by clouds, reflecting surfaces on the ground such as sea and snow. About 23% is absorbed in the atmosphere by water vapor and 48% is absorbed by the ground.
Spectrum distribution of the sunlight
There is only a visible spectrum of sunlight that humans can perceive. That is from 380nm to 740nm. Wavelength from 740 to 2500nm makes 40% of radiation reaches to the earth is not visible.
Visual transmittance of glasses
There are different types of glass available in the market and one of them is known as low emissivity glass or low-e glass. That type of glass operates mostly allowing visible spectrum of light and it blocks UV and infrared radiation in the meantime.
Seasonal performance of low-E glass
How does it can be applied to our household and what are the benefits of it. The obvious one would is blocking harmful UV rays. The main advantage is that it can reduce heating and cooling loads by controlling the heat transfer in the invisible spectrum of sunlight.
Low-e glass can help maintain heat by locking infrared spectrum of radiant heat energy to where it should belong. In summer, it helps by lower the heat entering into the house. In winter it helps by blocking most of the radiant heat escaping to the exterior. It does apply the same for different locations, different altitude with varying degrees of temperature in the world.