Glass coating transmits more than 100% PAR
Start-up company Physee discovered a way to increase PAR transmission of glass to 107% by adjusting a specific coating to the glass. A second coating could add heat production at the same time.
Physee is founded by a group of former students from the Delft University of Technology. They manufacture clever window coatings that produce data. One of the coatings they tested showed an increased PAR radiation transmission of glass by 4% already, while they expect 7% will be possible. While manufacturing glass the coating can be applied to last for 15 – 20 years. For existing glass it is possible to apply it every 2 – 3 years.
PAR radiation lays between 400 – 700 nm. The coating which they call PAR+ transforms a part of the radiation between 100 – 400 nm into a longer wavelength. This way, it contributes to growing light which results in raising production. It doesn’t seem to matter if the glass is diffuse or not.
As always with innovations, lots of questions remain. Can they guarantee the life span of the coating? How does the decrease of light in the 100 – 400 nm spectrum influence other growing conditions like pollination or fertilization? Physee plans to answer many remaining questions by tests in official research facilities.
Physee is able to catch the radiation over 700 nm, with another type of coating. This type can be used to contribute to heat the greenhouse. Apparently, both coatings can be used together.
Hagelunie is a sponsor of the research station in The Netherlands. Therefore, we will be on top of the results of the practical tests. When there is more information available, we will inform you. For more info, visit the Physee website or contact your Hagelunie risk specialist.