The SFL biosphere on the roof of the Science Tower is surrounded by energy glass. It generates electrical energy for operating the biosphere and is filtering the sunlight due to the dye of the energy glass – the filtered, transmitted light promotes the growth of plants.
The core component of energy glass is the “Grätzel-Cell” (also called dye-sensitized solar cell, DSC). Like photosynthesis in plants, this transforms sunlight into electricity using a dye. Grätzel cells consist of two coated glass panes whose interstitial space is filled with a dye and an electrolyte. As a result, the cells are not only transparent – energy-glass can harvest energy on both sides (the only transparent bifacial solar harvesting technology world-wide).