Geysir is clear float glass treated with a low-emissivity (low-E) coating on the outside of the greenhouse. This pyrolytic coating is applied online during the float glass production process and is extremely durable. Thanks to the coating’s low emissivity, the heat generated is kept inside the greenhouse, resulting in a significant reduction in the amount of energy consumed to heat the greenhouse.
This glass is then sandwiched between two durable anti-reflective (AR) coatings to maximise hemispherical light transmission and protect the glass from corrosion.
More info on Geysir glass on: https://www.agculture.eu/solution/geysir/