There is a high probability that the Ecodesign Directive of the European Union will include positive displacement pumps in the near future. The Ecodesign Directive sets the framework of a legislative efficiency guidelines of energy-related products (ERP) to reduce their energy consumption. However, positive displacement pumps are used in various applications that affect the attainable efficiencies. Consequently, a regulation for all positive displacement pumps on the pure basis of the efficiency is not sufficient. This paper illustrates the necessity of an application-related consideration of positive displacement pumps and provides two major steps towards an application-related efficiency guideline: firstly, a concept of data acquisition and analysis is presented and discussed. The concept aims to identify the energetically relevant applications of positive displacement pumps and to determine a relationship between the various pump types, their applications and energy consumption. Secondly, a physically based, type independent and easy to apply model of the efficiency of positive displacement pumps is presented and its suitability in the context of an efficiency guideline is discussed. The model has been introduced by the authors recently and describes the efficiency as a function of four dimensionless variables. A parameter identification and model application on four different pump types and 155 different pump sizes including 2680 operating points proves its practicability to compare different pump types.