Introduction The Long Term Development Statement (LTDS) in Common Information Model (CIM) provides standardised network data that enables interoperability between electricity network analysis tools. It provides a common data format to represent electrical network components and their relationships. This allows consistent data exchange across different software tools, such as PowerFactory and IPSA. The LTDS in CIM comprises several profiles, each describing a specific characteristic of the distribution network. These profiles are defined in accordance with the Common Grid Model Exchange Standard (CGMES) and the IEC 61970 family of standards. For further details, please refer to Form of Long Term Development Statement (LTDS) with particular attention to LTDS Grid Modelling Annex 1 – Grid Modelling Guidelines and LTDS Grid Modelling Annex 2 – Data Exchange Specifications. The latest version of the appendix is available through BSI GB CIM Engagement Hub.Scope of Data Published The present iteration of the LTDS in CIM is limited to Equipment (EQ), Short Circuit (SC), Short Circuit Result (SCR), and System Capacity (SYSCAP) profiles, in line with the Stage 2 LTDS CIM publication structure. The scope of each published profile is summarised below: EQ profile defines the physical structure of the electricity distribution network, including substations, transformers, feeders, switches, and related connectivity. SC profile provides short-circuit characteristics required for fault level assessment. SCR profile contains the results of short-circuit studies. SYSCAP profile provides system capacity information, including firm capacity and non-coincident maximum loading data. UK Power Networks is responsible for operating within three distinct distribution licence areas: Eastern Power Networks plc (EPN), London Power Networks plc (LPN), and South Eastern Power Networks (SPN). The LTDS CIM publication provides profile data for each licence area, organised according to these operational boundaries. For a detailed understanding of the data scope published in the November 2025 LTDS cycle, users should refer to LTDS Stage 2 Publication Notes, which set out the specific content and limitations of the dataset. The supporting documentation can be found on our library using the following link:  LTDS CIM Deliverables - May 2026 Shared Data Request Form This dataset has been triaged as 'Shared' (see attached data sharing risk assessment). To request access to this dataset, please register, login then complete the Shared Data Request Form Methodological Approach The models were developed by configuring all required LTDS CIM classes, attributes, and associations, while sensitive data was excluded to produce LTDS Stage 2 profiles. Conformity and Interoperability tests were performed iteratively to ensure usability, accuracy and alignment with the relevant standards. Quality Control Statement Quality control measures applied during the development of the LTDS CIM models include: Independent XML-based validation to confirm structural completeness and data exchange reliability. Application of the latest SHACL constraints to ensure compliance with current LTDS CIM schema requirements and guidance developed in coordination with Ofgem and the LTDS CIM Working Group, established under the ENA Data and Digitalisation Steering Group (DDSG) Work Programme. Assurance Statement The Network Insights Team collaborated closely with Data Interoperability Engineers and Modelling Engineers to ensure the LTDS CIM models meet the required standards of accuracy, consistency, and interoperability. This work was coordinated with Ofgem and the LTDS CIM Working Group, ensuring that all models published for the three licence areas reflect agreed methodologies and best practice. Other The LTDS Data Exchange Definition artefacts were developed to support Stage 1.3 of the CIM LTDS grid modelling. Publication notes were also produced to provide guidance on Stage 2 Profiles. All artefacts and notes for this release are available on the BSI Engagement Hub at: LTDS Stage 2 Publication Notes. For any further inquiries, please contact us at via email to networkinsights@ukpowernetworks.co.uk The dataset is updated every May and November in line with regulatory requirements and is intended to improve transparency, interoperability, and stakeholder engagement across the energy sector. You can download metadata information here: Eastern Power Networks (EPN)London Power Networks (LPN)South Eastern Power Networks (SPN) Alternatively, you can download dataset information: Metadata (JSON) Definitions of key terms related to this dataset can be found in the Open Data Portal Glossary: https://ukpowernetworks.opendatasoft.com/pages/glossary/