CC BY 4.0Copei, SebastianSebastianCopeiRülicke, LindaLindaRülicke2025-07-072025-07-072025https://publica.fraunhofer.de/handle/publica/48921610.1016/j.dib.2025.11183810.24406/h-489216With multiple national and international data space projects, the drive of this technology may change data-sharing processes disruptively. With the promise of sovereign, secured, and trustful data exchange, a data space seems perfect for closing the gap in inter-company communication through various domains. The energy domain in Germany is also currently in the digital transformation stage. With complex processes across multiple companies in regulated and unregulated scopes, the rigorous fulfillment of the General Data Protection Regulation (GDPR) and national security requirements is mandatory. However, data spaces seem to be a possible technology that can fulfill the requirements while allowing flexibility in implementing all needed processes. With this paper, we want to share our experiences with the implementation of a data space in the German energy domain. In addition to the general challenges and barriers that occur while creating a data space, we will outline specific challenges and barriers from the energy domain in Germany. Furthermore, we will present our solutions to overcome some of these challenges and barriers and collect them as Best Practices that can be adopted from other data space initiatives.enData SpaceEnergy Domain: ArchitectureChallengesBarriersjournal article