The European Union intends to reduce the energy consumption in the building sector. The European Directive 2010/31/EU requires the definition of national standards for nearly zero energy buildings. This article presents a research study supported as part of the research initiative “Zukunft Bau” of the Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety for the definition of a nearly zero energy building standard for new buildings in Germany. First, the methodology is discussed, then the first results of a variant study on a model building are presented and discussed.