Informal version of the Energy Saving Act 2009 (in German). The Energy Saving Act (EnEG) is the legal base for the German Government to issue ordinances concerning energy efficiency of buildings. (For practical requirements, have a look at the Energy Saving Ordinance and the Heating Costs Ordinance). The Energy Saving Act was adjusted in some points for the implementation of the European Directive on Energy Performance of buildings. The amendments essentially concern the addition of principles for energetic requirements on lighting systems as well as for the issuance of energy certificates. Underlined words were added in 2009, compared to the prior version of the year 2005. A further amendment (EnEG 2012) is currently under preparation.