## 4 Technological Challenges and Integration Issues
### Human and Organizational Factors  
While the technical aspects of a digital twin often receive the most attention, human and organizational factors are equally important to its success. The deployment, maintenance, and effective use of a pan-European digital twin present complex socio-technical challenges that rely on skilled personnel, institutional capacity, coordination across organizations, and a culture that is ready to embrace digital transformation [24]. Regardless of how advanced the technology may be, the twin will not achieve its intended value without the involvement of engaged and capable human actors [4]. A key barrier to digital twin implementation is the skills gap across the electricity sector. Developing and integrating digital twins requires interdisciplinary expertise in data science, software engineering, power systems modeling, and cybersecurity [24]. Although European transmission and distribution system operators have strong capabilities in electrical engineering and grid operations, many organizations, particularly smaller distribution operators, lack personnel with the digital skills needed to design, implement, and manage digital twin systems. According to the joint report by TSOs and DSOs, the shortage of human and technical resources is one of the most pressing challenges facing distribution system operators in their digital transformation efforts [4]. Limited staffing and competing operational demands make it difficult to dedicate time and expertise to innovation projects. These skill mismatches also affect areas such as advanced analytics, artificial intelligence, and IT architecture, which are becoming increasingly important for digital twin deployment [20]. Addressing this skills gap will require both upskilling in the current workforce and target the recruitment of new talent. Utilities must invest in training their existing personnel in the use of digital tools and may need to establish entirely new roles, such as digital systems architects, data governance officers, or grid simulation specialists [24]. EU-supported programs, including Horizon Europe and the BRIDGE initiative, are already contributing to the development of relevant curricula and training modules [43]. Events and platforms organized by ETIP SNET, including sessions focused on artificial intelligence and grid digitalization, reflect growing momentum in the sector to build digital capabilities [44]. However, these efforts must be significantly scaled up to meet the demands of the transformation envisioned through the digital twin [4]. Beyond individual skills, organizational change is another essential enabler. Implementing a digital twin often requires fundamental changes to workflows, organizational hierarchies, and decision-making cultures [24]. Grid operations that were traditionally guided by engineering judgment and established procedures may increasingly depend on model outputs and predictive analytics. This shift can encounter resistance, particularly when digital tools are perceived as opaque or when they appear to challenge established expertise. Building trust in the outputs of the digital twin, and in the broader move toward data-driven operations, depends on the availability of user-friendly interfaces, transparent decision-support systems, and phased implementation that delivers visible operational benefits [4]. Pilot projects that clearly demonstrate how the digital twin helped prevent a costly outage or optimized network reinforcement can be especially effective in generating internal support and acceptance [20]. Organizational silos within utilities present additional structural challenges. Digital twin projects require coordination across departments that have traditionally operated independently, including information technology, operational technology, planning, operations, and regulatory affairs. In many utilities, these departments have different priorities and use distinct terminologies, which makes sustained collaboration difficult.