As system hardening focuses on updating overhead lines and equipment, PG&E has to consider over 30,000 line-miles of transmission and distribution assets in High Fire-Threat Districts in its operation. Industry-wide adoption of lighter, stronger, and/or more heat-resistant infrastructure has been limited by cost, availability and longevity.
PG&E operates over 30,000 line-miles of Transmission & Distribution (T&D) assets in High Fire Threat Districts (HFTD). Current state-of-the-art technologies to detect faults in real-time and prevent ignition from these faults can reduce risk, but remain expensive, slow to install, and require tuning and maintenance to be effective.
- Real-time fault, flame or vegetation incident detection and wire de-energization
- Meaningfully cheaper or faster to implement than REFCL (defined below)
- Effective on multi-phase faults (i.e. simultaneous fault on three or four wires)
- Operates autonomously and transmits data in real-time
- Capable of providing fault or incident location within 1,000 meters
- Minimal false positive incidence
Category 1: “Monitor & mitigate” technologies for real-time detection of faults and prevention of arcing, sparking and other ignition events along T&D infrastructure
Problem statementPG&E operates over 30,000 line-miles of T&D assets in High Fire-Threat District (HFTD) areas. Wherever power lines remain above ground and among vegetation, it is critical to detect wildfire ignition risk and immediately respond to it. While some sensor- and data-based monitoring systems are already in use or in pilot, some important gaps remain:
- One innovative category of solutions currently being piloted, Rapid Earth Fault Current Limiter (REFCL), and related wires-down technologies, could be further enhanced. These technologies are resource-intensive, slow to install, and can be ineffective when faults occur simultaneously on two or more lines.
- Across the industry, up to 10% of current state-of-the-art capacitor banks can fail each year, and up to 10% of those failures can cause fire ignitions.
- Across the industry, current state-of-the-art sensor networks are unable to assess the exact location of faults in real-time.
- Across the industry, current state-of-the-art sensor platforms cannot cost-effectively monitor real-time pole & line conditions (e.g., vegetation contact, line slapping) at the pole level due to high installation access/labor needs and distributed power and communications limitations.
- Across the industry, current monitoring systems are not capable of detecting and communicating nearby sparks or flames in real-time.
Possible approachesTo work effectively, REFCL requires prior balancing of circuits, leading to possible phase rotations for customers, as well as installation of capacitor banks and other supportive equipment prior to operation. Any technical solution or process innovation that improves upon current state-of-the-art monitoring and/or mitigation capabilities – either by increasing functionality, efficiency or reducing cost – is of interest. Preferred alternatives or complements to REFCL include those that are cheaper, faster to install, or able to detect and de-energize multi-phase faults. Improvements to other current technologies include more reliable and/or safer capacitor banks and fault location detection technologies that work in parallel with DFA or EFD. Other gaps in today’s technology landscape include real-time pole-based condition monitoring and fire and flame detection. Also of interest are enabling technologies such as sensor installation methods and power and connectivity solutions for distributed and remote sensor networks, as well as mobile (e.g., aerial or drone-based) sensor networks.
|Industrywide Market Gap||Potential Solution Category
|8-10% of today’s capacitor banks can fail each year, |
and up to 10% of the cap banks
that fail can cause fire ignitions
(among the highest probability of
fire ignition of all distribution
|More reliable and/or safer
|Current sensor networks are pretty good at assessing |
“when” and “what” for grid failures,
but most are not capable of assessing
“where” with reasonable granularity.
|Fault location detection technologies
to work in parallel
with DFA or EFD
|REFCL is promising but has several limitations: |
not only can it be expensive and
slow to install, but it is not designed for
two or three lines and is not usable on four-wire systems.
|Rapid Earth Fault Current Limiter
(REFCL) alternatives for 3+ lines
(or faster to install)
|Today’s sensor networks do not provide the capability of measuring |
real-time pole & line conditions
(e.g., vegetation contact, line slapping) at the pole level.
|Pole-level condition monitoring
(e.g. physical disturbances)
Known approaches not of interest
- Software-based solutions without hardware componentry
- Procedural or workflow management solutions
Key success criteria
- At least 35% reduction in cost for the same wildfire risk reduction or at least a 35% reduction in wildfire risk at the same cost
- Demonstrated improvement over current state of the art technology
- For distributed sensors, technology must:
- Minimize cost and difficulty of installation
- Cost-effectively power itself (e.g. autonomously)
- Maintain constant network connectivity (to LPWAN, PG&E internal network, or PG&E-utilized third-party network)
- Simple integration with enterprise data analytics platform
- Commercially available in 1 to 3 years
- Real-time fault, flame or vegetation incident detection (within 100 meters) and wire de-energization with sensor placement interval no less than 3 km
- REFCL alternatives: meaningfully cheaper or faster to implement and/or effective on simultaneous multi-phase (i.e. three or four wire) faults