Stadtwerke Köln GmbH. is the infrastructure and services company of the City of Cologne. The company undertakes water supply and electrical gas heat and steam energy supply through the subsidiary RheinEnergie. Other subsidiaries provice waste management and housing services for the city in addition to operating the public baths. The subsidiaries Kölner Verkehrs-Betriebe (KVB) and Häfen und Güterverkehr Köln (HGK) operate the cities urban and industrial transportation systems respectively.