In an effort to eliminate less-predictable outages, PG&E has embarked on a five-year journey, with annual milestones, to reduce the vegetation-related SAIFI by more than 50% systemwide by 2011, ultimately driving SAIFI to 0.075. The entire program is self-funded through the Vegetation Management Improvement Initiative.
The PG&E Vegetation Management System Reliability Program is data driven. PG&E investigates all tree-caused outages at the time they occur and collects detailed information. The utility then uses five years of historical outage data to identify trends and pinpoint outage-prone protection devices. Once these factors are identified, the reliability team uses region-, species- and failure-specific outage data to determine the types of trees that should receive focused attention patrols.
Targeted locations with specific historical outage data are critical to the program's success. Without a targeted approach, costs would skyrocket, rendering the program inefficient and ineffective. Specially trained work planners organize and prescribe the work for a given protection device. Each selected protection zone is patrolled with a device-specific prescription. Specific trees are marked and detailed descriptions of the work are spelled out in the work-request documents given to the tree crews.
The work required to improve electric reliability is substantially different than the work required to maintain regulatory clearances. Outage data may drive crews to clear 200-ft-tall redwoods of nearly all overhanging branches or to cut mature fan palms down to the ground.
It is generally safe to assume that most people like reliable power and that most people like trees, and that they do not consider these things to be mutually exclusive. So PG&E has adopted a proactive communication strategy specifically tailored to customers who fall within reliability project areas.
Vegetation management reliability project planners use door hangers, local media releases and an automated customer notification system to alert, educate and communicate with affected customers and the surrounding community. The various platforms give a consistent message about the program and the new approach to improved electric reliability. These tools have been crucial in educating the customers and reducing roadblocks well ahead of the work. Customer satisfaction surveys show conclusive results. More than 86% of customers participating in the program rate their overall satisfaction as excellent, very good or good. This compares with a 77% satisfaction rate for routine work.
One full year does not make a trend, but initial results strongly suggest that the program is headed in the right direction. With a vegetation SAIFI score of 0.123 in 2007, a 0.075 SAIFI score is within our grasp and further reductions look more and more realistic.