Target Start Date
01/2026
Anticipated Duration
12 months
Objective
Reliability of an underground transmission system depends on highly skilled utility engineers working throughout the life cycle of design, construction, installation, operation, and maintenance of the system. It is essential to retain cable system institutional knowledge and support the next generation of technical leaders. The project addresses the following needs with knowledge, methods, and tools:
- Knowledge management of EPRI research and development project results and industry experiences
- Investigation results of advanced tools and techniques for effective cable system management
- Knowledge transfer on various topics covering design, construction, installation, operation, and maintenance of extruded and laminar dielectric cable systems
This project intends to provide resources and technical support to current and future cable engineers. Participants may be better equipped with the latest knowledge, technologies, and educational materials, resulting in more reliable and cost-effective transmission cable systems. Utility engineers can apply the results of this project by participating in educational sessions while interacting with industry subject matter experts and other experienced utility engineers. For example:
- The educational workshops and workshop proceedings can be used to equip utility engineers and improve work productivity for long-term system performance.
- The updated Underground Transmission Systems Reference Book and Increased Power Flow Guidebook can be used to validate system designs, improve system operation and maintenance, and increase or optimize ratings of transmission cable lines.
- The EPRI Green Book training proceedings can aid in cable engineers to better understand general principles and practices needed to provide reliable underground transmission systems.
Approach
This project focuses on knowledge management in underground transmission. It provides:
- Semi-annual educational sessions and proceedings.
- Updated EPRI Underground Transmission Systems Reference Book and Training Materials.
- Updated EPRI Increased Power Flow Guidebook.
Research Value
This project may provide the following benefits:
- Improved underground transmission system design
- Enhanced cable project execution
- Retention and/or transfer of institutional knowledge
- Reduction in overall installation, construction, operation, and maintenance costs
Anticipated Deliverables
| Deliverable | Description | Date |
|---|---|---|
| Underground Transmission Education Workshops (report) | EPRI intends to hold educational workshops in conjunction with the Underground Transmission Task Force meetings, twice annually. Topics include design, construction, installation, operation, and maintenance of both extruded and laminar dielectric cable systems. Workshop proceedings will be made available. | December 2026 |
| EPRI Underground Transmission Systems Reference Book (The Green Book)—2026 Edition (report) | The EPRI Underground Transmission Systems Reference Book (the Green Book) is a desk and field compendium on the general principles involved in planning, design, manufacturing, installation, testing, operation, and maintenance of underground transmission cable systems. The project team continuously updates the Green Book, focusing on one or two sections each year. | December 2026 |
| EPRI Underground Transmission Reference Book Training Proceedings – 2026 Update (report) | Report contains training session proceedings in: - Underground Transmission Cable Systems - Pipe-Type Cable Systems - Extruded Cable Systems - Installation, Construction, and Operations & Maintenance | December 2026 |
| Increased Power Flow Guidebook (The Platinum Book)—2026 Edition (report) | This report will be continuously augmented with updated and additional materials on the state of the science and best practices for increasing and optimizing power flow through underground transmission cables and their associated circuit components. | December 2026 |
Past Example EPRI Research on Topic
| Product ID | Title | Description | Published Date |
|---|---|---|---|
| 3002029513 | Underground Transmission SystemsReference Book (The Green Book) | Desk and field compendium on the general principlesinvolved in planning, design, manufacturing, installation, testing,operation, and maintenance of underground transmission cable systems. | 2024 |
| 3002029514 | EPRI Underground TransmissionSystems Reference Book Training Proceedings | Materials from Green Book training sessions structured inaccordance with the book’s diverse subject matters. | 2024 |
| 3002030267 | Increased Power Flow Guidebook(The Platinum Book) | State-of-the-art and best practices reference andguidebook on increasing power flow capacities of existing overheadtransmission lines, underground cables, power transformers, and substationequipment. | 2024 |
| 3002029515 | Underground Cable Fault LocationReference and Application Guide – 2024 Update | Summary of underground cable fault location methods andapplication of the methods for transmission cable systems. | 2024 |
| 3002027229 | EMF Management User’s Guide forUnderground Transmission Systems | A design guide for magnetic field management methodsbased on practical installations and for quantifying ampacity deratingeffects of magnetic field management methods. | 2023 |
| 3002024554 | Framework for the Comparison ofOverhead and Underground Power Transmission | This report provides a comparative analysis framework for69-kV through 500-kV overhead and underground transmission installations. | 2022 |
| 3002021332 | Life-Cycle Cost Guide forUnderground Transmission Cable Systems, Survey Results, and Case Studies | This report identifies key considerations to include in alife-cycle cost (LCC) analysis and general approach to an LCC analysis forunderground transmission cable systems, focusing on less-often consideredaspects of cost analysis, including operation, maintenance, repair, anddecommissioning. | 2021 |
| 3002019134 | Underground Transmission SystemProtection | Describes basic theories and options for cable systemfault protection, including special considerations for hybrid overhead and undergroundlines. | 2020 |