Scaling the Future – Interview-Based Insights on Scalability, Replicability, and Standardization in HYNET Demonstrations

This paper presents a structured comparative analysis of four demonstration sites under the Horizon Europe-funded HYNET project, which aims to deploy interoperable hybrid AC/DC electricity networks across Europe. Based on interviews conducted with demonstration leaders, the study identifies key enablers and barriers related to scalability, replicability, technical interoperability, and regulatory readiness. While each demo site addresses a distinct operational context from grid-forming control in weak islanded systems to cross-border High-Voltage Direct Current (HVDC) corridors and real-time digital twins, common themes emerge. These include adaptable control architectures, modular planning tools, and improved protection and communication frameworks. Significant challenges remain in standardization, infrastructure access, and market alignment. These insights contribute to the project’s Scalability and Replicability Analysis (SRA) and offer policy and industry stakeholders actionable guidance for the broader deployment of hybrid AC/DC systems.