Introduction

About

The digital transformation of the energy system offers numerous benefits, including enhanced connectivity among energy components, direct market access for end-users, and seamless integration of renewable energy sources. However, realizing these benefits requires addressing challenges such as ensuring end-users' adoption of digital technologies, addressing societal acceptance issues, engaging communities effectively, and ensuring decentralization and data sovereignty. Additionally, an integrated framework allowing effective data integration across the energy value chain also including data from other sectors, is required.

Figure 1: High-level view of the CELINE federated architecture

To address these challenges, CELINE introduces an innovative framework (see Figure 1) designed to promote the widespread adoption of digital technologies within the energy sector, thereby fostering seamless interaction and collaboration among energy stakeholders. It focuses on facilitating the adoption of localized, community-based, and digital-driven energy innovations that are user-centric, community-driven, and tailored to address the specific needs of geographical areas or communities. CELINE will conceptualize, co-design, develop, and demonstrate an open-source cross-sector data-driven digital ecosystem and toolbox, comprising digital twins of community energy systems and AI assistant tools, enabling the creation of tailored cross-sector data-driven services aimed at:

1. support community-led self-consumption and production schemes

2. enhance end-users' capabilities in managing energy resources, optimizing energy usage, and making well-informed energy-related decisions

3. empower end-users by improving their digital and energy literacy, enhancing user experience, and overcoming potential resistance and barriers.

CELINE tools and services will be tested in three real-world Demonstrators (Ds) across different European regions, offering diverse climate, geographical, and socio-economic conditions (Valencia/ES, Lappeenranta/FI, and Alpe Cimbra/IT).

Context

As Europe advances toward a digitally integrated and data-driven society, the concept of dataspaces has emerged as a cornerstone of the European data economy. Dataspaces aim to create interoperable, sovereign, and trusted environments for data sharing across sectors and borders, in alignment with EU values and legislation. Driven by strategic initiatives like the European Data Strategy, the Data Governance Act, and numerous domain-specific efforts, dataspaces enable organizations and individuals to collaborate through a federated, modular architecture that preserves data sovereignty and enhances interoperability. Within this evolving landscape, the development of dedicated tools to support the creation, governance, and operation of dataspaces is critical. This project responds to that need by designing and developing a data toolbox grounded in the principles and practices of Dataspace architectures. The toolbox will empower stakeholders to build and manage interoperable, trust-enabled data ecosystems aligned with current and emerging European frameworks.

Objective

The objective of this repository is to provide a state-of-the-art (SotA) analysis framed as a broad landscape review that informs the design and implementation of the CELINE data toolbox. The analysis identifies and evaluates key developments across regulatory, strategic, technological, and semantic domains relevant to dataspaces, clarifying that the inclusion of any specific initiative, technology, framework, or methodology does not imply CELINE’s endorsement or commitment to adopt it. Instead, the SotA serves to:

• Understand the policy context by mapping EU legislation and strategies that shape sovereign, trusted, and interoperable data flows.

• Survey active initiatives and programmes to reveal reusable reference architectures, certification schemes, and open-source building blocks.

• Analyse technical foundations and ontologies that underpin interoperability, data sovereignty, and cross-sector collaboration.

• Synthesise cross-cutting themes that influence the Dataspace paradigm and highlight gaps or innovation opportunities.

The insights gained will guide subsequent tasks and work packages, where final selection, adaptation, and integration decisions will be made according to concrete requirements, integration needs, and technical feasibility, in aligning CELINE with European priorities, leveraging proven methodologies, and maximising the project’s impact and relevance.

Scope of the Repository

The structure of this repository reflects a layered approach to capturing the ecosystem around dataspaces:

1. EU Policies & Recommendations: An overview of regulatory and strategic guidance from EU institutions that inform the design of interoperable and ethical data systems. A list of analysed EU policies & recommendations is presented in Table 1.

2. EU Initiatives and Programs: A survey of large-scale European efforts such as GAIA-X, EOSC, and European dataspaces that serve as contextual anchors. A list of analysed EU initiatives and programs is presented in Table 2.

3. Funded Projects: A targeted review of relevant Horizon 2020, Horizon Europe, and Digital Europe projects to derive lessons, gaps, and synergies. A summary of the analysed projects is presented in Table 3.

4. Ontologies and Data Models: An analysis of semantic assets that enable cross-domain data interoperability, discoverability, and governance. A list of analysed ontologies and data models is provided in Table 4.

5. Analysis of Key Themes: A synthesis of recurring insights related to trust frameworks, data sovereignty, federation, and sustainability in dataspaces.

6. Conclusion: A consolidation of findings and implications to guide the ongoing development of the project’s data toolbox.

Each chapter contributes to a comprehensive understanding of the current landscape, offering a foundation for innovation that is aligned, interoperable, and sustainable within the evolving European data ecosystem. The analysis spans multiple domains (e.g., energy, mobility, health, manufacturing) to extract transferable principles and best practices that can inform a generic yet adaptable toolbox for Dataspace development.

Table 1: List of EU Policies and Recommendations considered during the SotA analysis.

Table 2: List of EU Initiatives and Programs considered during the SotA analysis.

Table 3: List of funded projects analyzed for the SotA analysis.

Table 4: List of analyzed ontologies and data models.