In-depth knowledge from demonstrations is needed for the future development of facility management, related to the introduction of energy-saving devices, buildings and energy systems. Particularly there is a need to understand better how the concept of Energy Flexibility can effect energy saving strategies and innovation decisions. Using a district heating network installation as a case study (TU Delft university campus in the Nether-lands), this research investigates the opportunities and barriers that stakeholders en-counter. To save energy and to deploy renewable energy systems, the Technical University of Delft is looking for ways to lower the heat supply temperature in the local (heat) grid on its campus. This implies that the connected individual buildings on the campus will need to be able to manage their energy demand more effectively, taking into account the new grid requirements, as well as the local climate conditions and user needs for indoor comfort, while delivered network supply temperatures for heating are lowered. This innovation adoption study first analyses the motivations of stakeholders to change grid requirements at the TU Delft campus and the opportunities and barriers they encounter for introducing energy flexibility in the campus buildings, due to these changing grid requirements. The transition from a high to a medium supply temperature has far-reaching consequences on the facility management of the buildings and the redevelop-ment of the heat grid. Secondly, this study looks at the main results from comfort simulations and real-life experi-ments to transform the heating network with a smart control system, with the aim to provide relevant information on encountered opportunities and barriers regarding facili-ty management. Thirdly, the study discusses the encountered portfolio management opportunities and barriers from the viewpoint of innovation adoption. The research concludes that the introduction of a smart heat network can be successfully test-ed on an estate of buildings with one estate operator. The smart control system can lower the heat network supply temperature in an individual heat network branch, which can support the implementation of renewable energy systems. However, this requires a time shift in the energy use of individual buildings and technical modifications of hardware, devices, buildings and systems. The visibility of energy flexibility still needs to be improved and research results show an urgency to lower complexity for facility management. The lack of interoperability of building management, control and data transfer systems is an important practical barri-er for facility management. Limited suitable business models, the lack of framing of energy flexibility for sustainable portfolio management, and legal barriers can further hinder adoption of energy flexibility.@en