P35.015: Advanced Conductors
Objective
Advanced conductors provide increased current‑carrying capability, the potential for reduced conductor sag, and lower electrical losses compared to conventional aluminum conductor steel‑reinforced (ACSR) conductors. However, knowledge of the long‑term performance and durability of advanced conductors remains limited, particularly for newer product designs. In addition, utilities have identified a need for improved guidance related to the specification, selection, procurement, application, installation, inspection, and maintenance of advanced conductors.
This project is intended to address these knowledge gaps and provide transmission owners and operators with greater confidence in the application and long‑term use of advanced conductor technologies. The key objectives of this research are to support transmission engineers in applying advanced conductors effectively and with confidence by:
- Providing guidance on the selection, specification, and application of advanced conductors.
- Developing standardized test protocols to compare the performance, durability, and reliability of different advanced conductor designs.
- Performing empirical studies to better understand performance characteristics and degradation mechanisms associated with advanced conductors.
- Conducting laboratory evaluations of inspection and monitoring technologies applicable to advanced conductors.
- Performing empirical studies to refine installation practices and develop improved installation guidance.
- Collecting and synthesizing utility experience and insights to capture lessons learned from field applications.
Research Value
Anticipated benefits to the public and project funders include:
- Improved public and worker safety through the development of clear, technically sound guidance for the inspection, assessment, and maintenance of advanced conductors and their associated connector systems, reducing the risk of in‑service failures.
- Enhanced reliability and resilience of the electric transmission system by promoting best practices for the installation and application of advanced conductors and connectors, thereby reducing outage risk, and supporting continued delivery of electric service under increasing grid demands.
- A technical basis to support informed utility decision‑making in the selection, specification, and deployment of advanced conductor and connector technologies, helping ensure that public and ratepayer investments are applied efficiently and prudently while managing long‑term operational risk.
Approach
This project addresses critical issues related to the long-term performance of advanced conductors by undertaking specific tasks in 2027:
Develop Guidelines for the Specification, Selection, and Application of Advanced Conductors: This task develops a guide (which is intended to be updated each year) to assist utilities in the proper selection and application of advanced conductors. The following information is intended to be included: • Field and test experiences with different advanced conductors • Application case studies • Documentation and characterization of various types of conductors • Review and development of technical specifications of the different advanced conductor types • Review of the various standards associated with advanced conductors
Advanced Conductor Ratings Calculator: The initial version of this calculator was completed in 2026. This calculator helps utilities better understand the temperature and current ratings for advanced conductors. In 2027, more advanced conductor types are intended to be added to the calculator, and specific functionality improvements are intended to be made.
Update Guidelines for the Installation of Advanced Conductors: Generally, composite core conductors have different handling and installation requirements, compared to traditional steel core conductors. Typical line installation crews are not as familiar with advanced conductor installation requirements compared with the traditional conductors. Most of the premature advanced conductor failures have occurred due to improper installation practices. This task is intended to compile best practice guidelines based on manufacturer recommendations and utility experience.
Carbon Core Conductor Qualification Summary Report: In 2027, results from the EPRI developed Carbon Core Qualification test are intended to be compiled and documented in a single report. Several different conductors have been evaluated since the last compilation report which was released in 2022.
Perform Qualification Testing of Carbon Core Conductors: Because carbon core advanced conductors have only recently been developed, there is a lack of information on how utilities can qualify them for application on their transmission systems. In 2027, this task intends to test and document the results of the De Angeli-Prodotti ACCM conductor. This information can be used by utilities to properly evaluate advanced conductors.
Thermal-Mechanical Testing of Conductors and Connectors: Newly designed connectors to be used with advanced conductors are intended to be tested both thermally and mechanically using an EPRI developed heat cycling test.
Identify Best Practices for the Maintenance of Advanced Conductors: Advanced conductors can operate at temperatures more than 150°C. These temperatures could pose a risk for utility workers and the tools that they use. This task intends to evaluate the effects of high temperature on workers and the tools they use, as well as investigating the effects of these tools on the conductors. The 2027 tasks are intended to build on the initial 2026 tests which focused on the thermal effects on tools attached to the high temperature conductors.
Evaluate Field Aged Conductors and Connectors: This task intends to provide an update on the results of evaluations performed on aged Advanced conductors. Through this evaluation, it is envisioned that a better understanding of the aging impact on the electrical and mechanical performance of these conductors may be obtained.
Provide Tools and Resources on The Transmission Resource Center: The following calculators, tools, result summaries, and references are planned to be available on the Advanced Conductor Transmission Resource Center:
| Resource Title | Resource Type |
|---|---|
| Carbon Core Conductor Qualification Testing | Results Summary |
Anticipated Deliverables
| Deliverable | Type |
|---|---|
| Carbon Core Conductor Qualification Testing: De Angeli Prodotti ACCM | Technical Update |
| Carbon Core Conductor Qualification Testing: Summary of Previous Testing | Technical Update |
| Maintenance of Advanced Conductors | Technical Update |
| Advanced Conductor Ratings Calculator | Web Application |
| Guide for the Selection and Application of Advanced Conductors | Technical Update |
Past EPRI Work on Topic
| Product ID | Title | Description | Published Date |
|---|---|---|---|
| 3002032803 | Environmental Impact on Advanced Conductors: Fire Exposure | This report details information on exploratory fire exposure testing on a carbon core and a steel core conductor. | December 2025 |
| 3002030304 | Advanced Conductor Specification Guide | This report aims to provide utilities with information on developing a specification for procuring advanced conductors and connectors. | December 2024 |
| 3002027132 | Mechanical Testing of a New ACSS Connector (Solo) | This report details the testing and results obtained from the static, ambient, and elevated temperature tests on the Solo ACSS connectors (splices and dead-ends). | December 2023 |