Abstract Capital goods manufacturers aim to fulfill customer requirements. Since a while they offer their customers not only a pure technical solution but rather a technical product including customized services. The integration of a product and services is called technical Product-Service Systems (PSS). The objective is to support customers with different services over the entire lifetime of the product and to ensure a long and successful relationship between capital goods manufacturers or PSS providers and their customers. However, beside customer needs PSS providers have to consider governmental and societal requirements as well. They have the responsibility to offer sustainable PSS by improving the sustainability of the technical product or of the service as well. In the scientific literature, different research projects assume that PSS shall be used to achieve sustainability goals and are able to reduce the ecological impact of industry. Nevertheless, this assumption is not proven by any of the research projects and no evidence has been presented in a use case yet. To evaluate the environmental impact of PSS, an approach for an ecological assessment of PSS is required. Currently, an approach, which enables PSS providers and their customers to assess, compare and evaluate the sustainability of PSS, does not exist. Therefore, this thesis strives for the development of a concept to analyze and reduce the Cumulative Energy Demand of technical PSS (CED.PSS). The CED is a method of the life cycle assessment which is described in the VDI guideline 4600. The method will be taken as a base for developing a concept considering PSS specific properties. The most crucial PSS-specific property for instance is the interdependence between the product and service elements. Finally, the validation of the concept will be demonstrated against a use case of the machine tool industry.weiterlesen