The results are clear
Our collectors are fitted with solar glass that is highly translucent and very strong. It’s intended as maximising the amount of solar energy that is captured by the collector absorber plates while protecting them from impact damage. To explain, this, it’s first necessary to understand how a solar collector uses the ‘greenhouse-effect’ phenomenon to heat water.
The sun’s rays that fall on the glass cover are a form of short wavelength radiation. Most of the solar radiation passes through the glass but some is reflected or absorbed. The transmitted portion of solar radiation that reaches the black absorber plate heats it and the water that is contained inside. The hot absorber also re-radiates thermal energy (a form of long wavelength radiation) which, in the absence of a cover, would escape and allow the plate to cool. The glass cover, however, acts as a reflector of the long wavelength radiation and bounces it back to the absorber, thereby containing the heat. Glass that has higher iron levels absorbs more solar radiation and allows less to reach the absorber plates. Low-iron glass can transmit about 91% of the incident solar radiation. Envirosun solar glass is produced with very low levels of iron impurities. Envirosun solar glass is also tempered using a heat-treatment process.