Updates & Events
Project Tasks
In 2026 we are planning to undertake several tasks in P35.013, Ratings and Increased Power Flow, including those listed below:
- Apply Novel and Emerging Technologies: There are many providers in the Grid Enhancing Technologies space (GETs). EPRI routinely identifies the newest technologies and updates to existing technologies to increase member awareness. With the number of DLR technologies increasing, it can be challenging to understand how to construct a pilot project, how to leverage a pilot to phase into operational use, and how to scope timelines and budgets. As part of 2026 efforts, the ratings team will provide recommendations based on lessons learned from multiple field evaluations with US utilities.
- Measure Emissivity and Absorptivity of Conductors from the Field: For both line ratings, LiDAR modeling, and IR inspection it is important to have accurate numbers for conductor emissivity and absorptivity. These values are often assumed; however, EPRI has developed tests that can directly measure samples provided by utilities that are new or removed from service. In 2026 an update will be provided on test results and the potential cost/benefit tradeoffs of coatings from a ratings perspective.
- Outline Benefits and Drawbacks of Increased Power Flow Scenarios: Utilities face many challenges in getting upgrades and new construction projects accepted. This task maps different upgrade scenarios to the challenge areas such as corona loss, EMF, cyber security, etc. to aid engineers in identifying “least regrets” options when considering upgrades to existing lines. A 2025 report addressed cyber-security, 2026 research will focus on EMF challenges that occur based on different types of upgrade/uprating including the linkage between EMF and right-of-way width.
- Document Uprating for Unique Scenarios: Datacenters, Storage, and Renewables: This task leverages existing EPRI learnings and upcomong utility projects to scope potential issues with unique capacity demands or unique upgrade types. While this can encompass a large range of challenges, the focus for 2026 will investigate the challenges of uprating existing lines to accomodate the high energy demand from data centers and AI.
- Update The Platinum Book: The Increased Powerflow Guidebook (The Platinum Book) is updated annually and covers all aspects of uprating. The guide covers overhead lines, underground cables, substations, transformers, and the economics of staged upgrades. As part of this task EPRI collates materials from published EPRI reports and industry standards for power flow such as IEEE, IEC, and CIGRE. For 2026 EPRI plans to update discussions of CIGRE TB 601 ensure sections for both twisted pair and coated conductor are brought up to date.
- Document Grid Enahancing Technologies (GETs) Field Trials: Many utilities are working with EPRI to pilot an emerging technology, such as DLR sensors, to get hands on expereince with the new tools and practices. EPRI collaborates with members to provide guidance, capture lessons learned, and provide data needed to do performance evaluations. The findings are brought back to members via presentations by the host utility which are then added to the TRC.
- Develop Guidance on Radial Conductor Temperatures and Ratings: Due to the fundamental properties of heat transfer transmission conductors are hotter at the core than the outer surface. The increased core heat can lead to line sag being greater than projected in software tools. Following the plans shown in the 2025 report , lab testing and modeling will be performed during 2026.
- Evaluate Weather Models and Forecasted Ratings: While historic weather data is readily available in many areas, what the forecasted weather conditions were is often not stored or available due to the extreme volumne of data to be managed. In 2026 the ratings team will gather forecasts looking forward for several weather models in multiple locations that can be verified against measurements in the field. This data can be used to help inform the uncertainty of short term AAR and DLR forecasting in future analysis once a statistically significant amount is collected.
- Develop Guidance for Accurate LiDAR Measurement Technique: Errors in LiDAR data and line clearance models can contibute to false positives and false negatives when defining the need to upgrade the transmission system. Two recent reports have documented best practices for LiDAR data collection and understanding what options are available to mitigate clearance contraints based on cost and effectiveness. Ongoing study is underway to collect additional LiDAR data which can be validated by physical measurements, which will include performing LiDAR and photogammetry data collection at the EPRI Lenox lab using a range of technologies for data capture and analysis.
- Document Utility Experience of Adoption of New Regulatory Requirements and Industry Standards: Utilities are required to adjust to ever changing regulatory requirements and industry standards. This task seeks to provide workflows and best practices to help utilities navigate these changes efficiently and to capture the potential risk exposure of different adoption strategies. During 2026 this task will track utility experiences with adoption of FERC Order 881 in the US, and continue to catalog changes to exising capacity standards and regulations. Interim findings may be discussed at Task Force or similar meetings.
Below is a graphic of all tasks currently included as part of this project. It is important to note that it is not possible to prioritize every task each year. Some tasks are long term efforts that result in a deliverable after several years, while some are short term and have deliverables during the year they are focused on. A brief task description for each is included in the carousel. The ratings team welcomes member input on tasks that should be added, removed, or be prioritized in the coming years.
2026 Engagement Opportunities
| Event Name | Date | Location | Contact | Information |
|---|---|---|---|---|
| EPRI R&D Information Exchange Webcast (P35.013) | January 27 10:00 - 11:30 am | Webcast | Justin Bell | Meeting Information |
| Transmission and Substations Task Force Meeting | February 9 - 12 | Charlotte, NC EPRI Offices | Rachel Moore | Meeting Information |
| EPRI R&D Deep Dive Webcast: (P35.013) | March 26 | Webcast | Justin Bell | More information coming soon |
| Transmission & Substations Advisory Meeting | March 30 - April 1 | Charlotte, NC EPRI Offices | Rachel Moore | Meeting Information |
| EPRI R&D Project Update Webcast: Line Ratings (P35.013) | May 19 11:00 am - 12:00 pm ET | Webcast | Justin Bell | More information coming soon |
| Overhead Transmission 2025 ARP Rollout #1 | June 18 10:00 - 11:30 am ET | Webcast | Rachel Moore | More information coming soon |
| Overhead Transmission 2025 ARP Rollout #2 | July 30 10:00 - 11:30 am ET | Webcast | Rachel Moore | More information coming soon |
| Transmission and Substations Task Force Meeting | August 10-14 | Charlotte, NC EPRI Offices | Rachel Moore | More information coming soon |
| Transmission & Substations Advisory Meeting | August 31- September 2 | Rachel Moore | More information coming soon | |
| TLW and HTC Matrix Software Demonstration | September 10 10:30 am - 12:00 pm ET | Webcast | Justin Bell | More information coming soon |
| EPRI R&D Deep Dive Webcast: Update on DLR Status in Industry (P35.013) | 10/22/2026 | Webcast | Justin Bell | More information coming soon |
| EPRI R&D Project Update Webcast: Line Ratings (P35.013) | December 2 11:00 am - 12:00 pm ET | Webcast | Justin Bell | More information coming soon |
2026 Anticipated Deliverables
| Deliverable | Deliverable Type |
|---|---|
| DLR Field Demonstration Guide | Technical Update Report |
| EMF Tradeoffs with Uprating | Technical Update Report |
| Uprating for Data Center Load Growth | Technical Update Report |
| Results of Emissivity and Absorptivity Testing 2006–2026 | Technical Update Report |
| EPRI Increased Power Flow Guidebook—2026: Increasing Power Flow inLines, Cables, and Substations (The Platinum Book) | Reference Book |
| Transmission RatingsWorkstation: 2026 | Software |
2025 Engagement Opportunities
| Meeting | Date | Location | Information |
|---|---|---|---|
| EPRI R&D Information Exchange Webcast: TopoloNet, New Technology (P35.013) | February 10 11:00-12:00 PM |
Webcast | Meeting Materials |
| Increased Overhead Transmission Capacity Task Force | March 10-13 (In-person) March 17-20 (Virtual) |
Charlotte, NC | Meeting Materials |
| EPRI Overhead Transmission Program (P35) New Supplemental Launch Webcast | April 3 2:00 pm - 3:00 pm ET |
Webcast | Meeting Materials |
| EPRI R&D Information Exchange Webcast: BPA DLR Field Trial (P35.013) | April 17 10:00-11:30 pm ET |
Webcast | Meeting Materials |
| EPRI R&D Project Update Webcast: Line Ratings (P35.013) | May 14 10:00-11:00 AM |
Webcast | Meeting Materials |
| Overhead Transmission 2026 ARP Rollout #1 | July 17 10:00 am - 11:00 pm ET |
Webcast | Meeting Material |
| Overhead Transmission 2026 ARP Rollout #2 | July 24 2:00 pm - 3:30 pm ET |
Webcast | Meeting Material |
| Increased Overhead Transmission Capacity Task Force | August 18-22 (In-person) August 25-29 (Virtual) |
Charlotte, NC | Meeting Materials |
| EPRI R&D Information Exchange Webcast: Update on DLR Status in Industry (P35.013) | October 20 9:00-10:30 am ET |
Webcast | Meeting Materials |
| EPRI End of Year Webcast: Line Ratings (P35.013) | November 17 11:00-12:00 pm ET |
Webcast | |
| TRW Training | December 3 3:00-4:00 pm ET |
Webcast | Meeting Materials |
2025 Deliverables
| Product ID | Name |
Type |
|---|---|---|
| 3002032786 | EPRI Increased Power Flow Guidebook—2025: Increasing Power Flow in Lines, Cables, and Substations |
Guidebook |
| 3002032204 | Transmission Ratings Workstation: 2025 Beta |
Pre Software |
| 3002032787 | Transmission Ratings Workstation: 2025 Final |
Final Release |
| 3002032788 | Technical Review of Methods Used to Determine Dynamic Line Ratings (DLR) |
Final Report |
| 3002032789 | Increased Transmission Line Capacity Projects 69 kV and Above |
Technical Update |
| 3002032790 | Radial Temperature Effects on Conductors and Ratings: State of the Science |
Technical Update |
| 3002032791 | Uprating Project Stakeholder Coordination: Cybersecurity for Rating Engineers |
Technical Update |
Key Deliverables
| Product ID | Name |
Type |
|---|---|---|
| 3002030550 | Dynamic Line Ratings |
Whitepaper |
| 3002024452 | Guidance for clearance limited lines: LiDAR, UAS, and ratings best practices |
Technical Update |
| 3002027075 | Guide for Application of Weather and Forecast Models to Line Ratings |
Technical Update |
| 3002027077 | Summary of Existing Rating Practices and Considerations for Emergency Ratings |
Technical Update |
| 3002027082 | Utility Experiences with Dynamic Line Rating Technologies |
Technical Update |
| 3002027093 | Improved Methods Identifying At-risk and Wind Sheltered Spans |
Technical Update |
| 3002024453 | Using risk to establish seasonal ratings: updating to 4 seasons |
Technical Update |
| 3002024561 | Quick Insight: Ambient Adjusted and Dynamic Line Ratings on Transmission Facilities |
Whitepaper |
| 3002021564 | Ambient Adjusted Ratings Application Guide |
Technical Update |
| 3002021565 | Line Ratings Sensor Field Trials - Phase 2: LineVision V3 |
Technical Update |
| 3002020158 | Summary of Recent Increased Transmission Line Utilization Projects: 115 kV and Above |
Technical Update |