Bosch Solar Energy AG was a German solar wafer and solar cell manufacturer, based in Erfurt, which specialized in crystalline silicon-based photovoltaic (PV) products, as well as thin-film modules using amorphous silicon and CIGS absorber materials. The company consisted of the various divisions for silicon, wafers, solar cells and modules, research and production facilities in Germany and France and plans were made to open a production line in Malaysia. It has been listed on the German stock exchange since 30 September 2005 and on 19 December 2005 its shares were admitted to the TecDAX. The enterprise was founded in 1997 as ErSol Solarstrom GmbH & Co. KG.