When heating systems in residential buildings are exchanged, the new renewable heat act of Baden-Württemberg, one of the federal states of Germany, requires to cover at least 10 percent of the heating need by renewable energy. The act came into force with the beginning 2010. A similar act for new buildings in whole Germany is already in force since middle of last year.
Alternative measures include additional insulation of the building envelope. With the renewable heat act for renovations the responsible Minister for the Environment, Tanja Gönner, is expecting an impulse for the renewable energy industry, but also for building renovation.