Plus energy - a new energy performance standard in Germany for both residential and non-residential buildings

Germany possesses a long tradition in energy-saving construction and has continuously tightened the energy performance requirements and extended the balancing scope in its energy-saving ordinance. In the last few years, several buildings with energy concepts that have the aim of generating more energy than the building needs (if compared in an annual balance) have been designed, realized and monitored - so-called plus energy buildings. This article presents selected examples of the plus energy approach for both residential and non-residential buildings along with their key technologies and available research initiatives dealing with the issue. It also discusses the different possibilities for defining the notion of plus energy and points to ongoing further developments for additional building types and settlements.