Four ways utilities are modernising vegetation management

While vegetation is an essential part of our ecosystem, it’s also the single largest cause of electric power outages in the US, writes Gregor Wilke of Trimble. According to the solutions engineer, advances in digital technology connect data and workflows for streamlined vegetation management operations and maintenance.

The US electricity network consists of over 7,300 power plants, nearly 200,000 miles of high-voltage transmission lines, and millions of miles of low-voltage distribution lines and distribution transformers. It’s essential for utilities to manage the vegetation growing around these assets to decrease the risk of wildfires and power outages and ensure safety for residents and communities. At the same time, vegetation management is a top operational expenditure and entails substantial risk.

Cutting down trees and trimming branches requires specialized equipment and trained personnel, which can be expensive, especially in a large service area with dense vegetation. Although vegetation management costs vary depending on a range of factors, Accenture estimates that utilities typically spend $6 billion to $8 billion annually to clear vegetation from overhead lines. Failure to comply with vegetation clearance requirements set by the North American Electric Reliability Corporation (NERC) can result in steep fines for US utility providers.

More reliable power delivery with digital technology

Despite the growing utility network, many electric utilities still rely on conventional vegetation management methods such as scoping for hazard trees with helicopter or foot patrols or using antiquated programmes and paper processes that create data silos and communication gaps. These methods rely on labour-intensive field work, which introduces human error. Improperly measured trees or vegetation missed by the human eye, especially on steep slopes, can pose a hazard to utility lines. It’s also difficult for workers to find and return to a hazard tree spotted by air or foot because these methods don’t capture a precise location.

Many utilities are finding that conventional vegetation management methods aren’t suited to address today’s challenges and are turning to technology advances, such as enterprise asset management solutions that connect data and workflows to streamline operations and maintenance efforts.

These modern vegetation management practices incorporate:

1. Digital workflows

Utilities require better data to reduce outages, meet budget constraints and build more resilient networks. However, harnessing and effectively using that data is often a significant challenge. A single solution that operates across all aspects of vegetation management will eliminate silos and inefficiencies by coordinating office and field operations, integrating data from multiple sources and applying artificial intelligence to identify and categorize hazards automatically. Data from a centralized source is more readily accessible by relevant teams and provides the basis for comprehensive data analysis to inform future action plans and asset investment decisions.

In the field, foresters can use a mobile device to evaluate hazard trees, track inspection data, capture digital signatures when notifying landowners or email inspection reports to landowners who weren’t present during a visit. Digitizing landowner notification workflows eliminate time-intensive activities such as physically distributing door hangers or creating and mailing maintenance notification letters to landowners.

Vegetation programme managers who use digital workflows benefit from being able to efficiently track contractor and utility staff progress, monitor circuits slated for routine maintenance and evaluate how hazard trees will affect the network. Based on this data analysis, vegetation managers can better prioritize work by targeting high-risk areas to maximize the impact of available maintenance funds while also averting the greatest risks to the public.

2. Spatial insight

Effectively managing utility assets requires knowing what they are and where they’re located. A Geographic Information System (GIS) is a powerful tool that allows utilities to manage and analyze large amounts of data related to vegetation management. It provides a way to visualize and analyze data related to vegetation, weather patterns and other factors that impact vegetation growth.

GIS technology automatically organizes assets by location, creating a system of record and history of work activities performed on individual spans, bays, towers and circuits. Incorporating GIS data layers, such as landowner parcel information, wildfire risk, protected species ranges and outage information, gives vegetation managers critical data to inform important decisions.

3. LiDAR

Utility companies can generate a digital model of their networks by converting classified LiDAR point clouds into GIS information. A LiDAR scan creates a more accurate GIS inventory of assets such as poles, structures, spans, and bays by capturing the precise X, Y and Z coordinates. With point-cloud data from a variety of aerial or ground-based sources, an electric utility can use its existing minimum voltage clearance distance (MVCD) standards or those from NERC to create a canopy-coloured risk map of all vegetation along the network.
Tree and brush canopy data is also derived from LiDAR and determined by radial distance (grow-in risk) and a tree’s likelihood to fall and come in contact with conductors (fall-in risk). This insight into which trees or brush need immediate attention can reduce operating expenses and manual labour costs by removing the need for costly helicopter line patrols or boots-on-the-ground assessments.

4. Augmented reality

Pinpointing individual trees that require assessment is complex, particularly when working in remote homogeneous forests with lengthy spans. Using outdoor augmented reality systems, fieldworkers can visualize LiDAR points and symbology superimposed on the image of real locations and mark problems on a mobile device in real-time while in the field. This takes the guesswork out of locating trees and expedites work by removing uncertainty around the vegetation in question.

Vegetation management is a complex and challenging issue that requires a sound strategy, along with careful planning, coordination and execution. Ensuring the safe and reliable delivery of electricity, while minimizing environmental impacts and costs, requires utility companies to rethink vegetation management and consider solutions that allow them to capture and analyze data from multiple sources to identify risk and organize mitigation efforts.

The powerful combination of digital workflows, GIS layers, LiDAR-classified point clouds and augmented reality in one end-to-end solution can help utilities reduce costs, drive operational efficiency and get one step closer to a more sustainable and resilient electrical grid.

ABOUT THE AUTHOR

Gregor Wilke is a certified arborist, a certified utility specialist, and a trained asset management professional with nearly a decade of experience helping utilities improve their vegetation management programmes. Currently a Solutions Engineer at Trimble, he helps utilities solve complex vegetation management problems using innovative technologies.