The Baltic 1 grid connection links EnBW's offshore wind farm of the same name to the 50Hertz transmission system and is the first German offshore wind farm (OWF). It is located approximately 15 kilometres north of the Fischland-Darß-Zingst peninsula. 21 wind turbines generate a total of 185 gigawatt hours yearly, which could supply 50,000 households. The voltage is transformed in the Bentwisch substation near Rostock, and connected to the onshore grid by 50Hertz. EnBW Baltic 1 has been operational since 2 May 2011.