Pacific Gas & Electric (PG&E) has demonstrated dynamic line rating (DLR) and asset health monitoring (AHM) technology to bring together sensors, real-time analytics and partner offerings to optimise electric transmission line capacity and proactively monitor asset health.

PG&E and project partners recently completed hardware field installations and vendor dashboard setups, achieving trial deployment status across all technologies.

This milestone reflects PG&E’s broader strategy to expand and upgrade substation and transmission line capacity, reduce congestion, and ensure reliable service during extreme weather events such as heat waves and high winds.

DLR technology helps utilities determine how much electricity powerlines can safely carry by using real-time weather data such as temperature and wind speed. Instead of relying on fixed limits, it adjusts the rating as conditions change, so utilities can send more power through existing lines without building new ones.

By testing and validating DLR and AHM, PG&E aims to create pathways for grid modernisation, unlock hidden capacity, improve reliability and integrate more renewable energy, while saving money in the process by optimising its existing assets and avoiding costlier traditional infrastructure upgrades.

“This project is a critical step in modernising California’s grid,” said Mike Delaney, vice president at PG&E. “Fundamentally, this project is focused on leveraging new technology to save California’s families and businesses money. If this test is successful, we see a path to unlock millions of dollars per year of cost savings through dynamic line rating and asset health monitoring technologies.”

PG&E (www.pge.com) is collaborating with the Electric Power Research Institute (Epri), which serves as the project’s technical advisor, to perform an independent evaluation of the DLR and AHM technologies over an 18-month field demonstration.

Technology partners for this project include:

• Heimdall Power (www.heimdallpower.com): Heimdall’s DLR functions like a smartwatch for the power grid. Its sensors deliver real-time insights into transmission system health and performance by measuring powerline temperature, sag, current and micro-climate weather conditions. PG&E is leveraging the Neuron sensors’ real-time data, with predictive analytics in Heimdall’s cloud-based platform, to evaluate the capability for safely increasing line use and reducing grid congestion, all without costly infrastructure expansion.
• Prisma Photonics (www.prismaphotonics.com):Prisma is deploying its PrismaPower beacon devices at two PG&E substations, one in Humboldt County and one in San Luis Obispo, to monitor 130km of transmission lines, all without installing any equipment on the powerlines. PG&E is evaluating the company’s DLR and AHM applications: PrismaCapacity, PrismaClimate and PrismaCircuit. These tools provide continuous monitoring of line capacity, environmental conditions and circuit health, offering a holistic view of grid performance. Prisma’s technology aims to transform PG&E’s existing optical fibre infrastructure into a sensing system, enabling wide-area monitoring across difficult terrain without costly sensor installations on towers or conductors. This approach aims to address California’s grid problems from data centre demand, extreme weather and aging infrastructure, delivering actionable insights on powerline ratings and asset health with precise location data that could help utilities increase efficiency while maintaining safety and reliability.
• Sentrisense (www.sentrisense.com): Sentrisense provides real-time monitoring for overhead power lines, combining DLR and AHM in a fully autonomous field device, the Sentri sensor. The Sentri attaches directly to electric transmission and distribution powerlines, delivering continuous data on temperature, sag, vibration and conductor fatigue. By tracking these parameters in real operating conditions, Sentrisense helps utilities detect early signs of degradation, improve grid reliability and operate lines closer to their true capacity. PG&E is evaluating the technology as a potentially cost-efficient way to extend the lifespan of critical assets and support data-driven maintenance across the grid.
• Smart Wires (www.smartwires.com): Smart Wires’ grid enhancing technologies (GETs) help utilities gain more capacity, flexibility and visibility from the transmission system they already have. SmartWires’ portfolio includes SmartValve, an advanced power flow control (APFC) option, and Sumo, a DLR software platform that uses real-time and forecasted weather data to show how much power each line can safely carry throughout the day. Sumo’s insights can improve situational awareness, support decisions around loading and congestion, and reduce the need for major grid expansions. As part of this project, PG&E is evaluating how Sumo works alongside DLR and AHM tools to strengthen overall system performance and resilience.

Founded in 1972, Epri (www.epri.com) is an independent, non-profit energy research and development organisation, with offices around the world. Its experts collaborate with more than 450 companies in 45 countries.

With vendor dashboards now live and installations completed across multiple substations and transmission corridors, PG&E is testing these tools’ ability to reduce congestion, enhance reliability and prepare the grid for the challenges of extreme weather and the growing demand for renewable energy.

For more information about PG&E’s R&D and innovation efforts, visit www.pge.com/innovation.

• Epri has announced a global initiative to modernise how the electric sector detects, anticipates and responds to emerging risks and manages increasing complexity in an era of rapid change. The effort, Rapid Adaptation of Grid Defence, Analytics & Resilience (Radar, msites.epri.com/radar), will provide a scalable framework, tools and training to help the sector strengthen grid resilience and reliability.