2. Background
Pacific Gas and Electric Company (PG&E) is an investor-owned public utility providing both electricity and natural gas service in northern and central California. For electricity service, it serves approximately five million customers through an interconnected and integrated system that generates, transmits, and distributes electric energy over a 70,000 square mile service territory.
The Proposed Project is located in western Santa Barbara County. The primary population centers in the project area are Lompoc, with a population of 41,099, and Buellton, with a population of 4,292.2
The purpose of the project is to improve the electrical reliability of the Cabrillo - Santa Ynez 115 kilovolt (kV) power line by reconductoring. The power line experienced six line outages due to equipment failure in 2008. Five of these outages were due to deteriorated conductors or insulator failures. The existing 4/0 All Aluminum conductor (AAC) and conductors located along 14.1 miles of the single-circuit power line are corroding, making the line brittle and prone to failure. The primary purpose of the power line upgrade is to prevent future power line failures.
The existing Cabrillo - Santa Ynez power line was upgraded from 70 kV to 115 kV with distribution-style dead-end shoes in 1988. This upgrade cost-effectively provided strength to meet tensioning requirements for this line. Subsequent investigation determined that this style of distribution design causes excessive bending of the conductor. The sharp bends, when exposed to the frequent local winds, create cyclic fatigue in the conductor, resulting in increased failures.
The Cabrillo - Santa Ynez power line is located in a coastal climate. This climate produces foggy and windy conditions throughout the year, which has contributed to the accelerated deterioration of the existing conductors and associated hardware, causing frequent failures. The Proposed Project would replace aging wood poles with new light-duty steel poles, and outdated or deteriorated hardware with an upgraded conductor, new insulators, and other required hardware along 14.1 miles of the existing power line. The remainder of the approximately 80-mile 115 kV transmission loop that serves over 71,000 customers in the general area between Santa Maria, Lompoc, Santa Ynez, and Solvang does not require reconductoring because it currently uses the new multi-chip model (MCM) AACs.
As well as improving reliability, the Proposed Project will also allow PG&E to meet General Order (GO) 95 clearance standards and to provide sufficient transmission voltage in the area during peak and abnormal operating conditions.
PG&E anticipates the Proposed Project will last approximately 15 months. The schedule proposed is to begin construction in Spring 2010 with a completion date of June 2011.3
2 Population estimates are from 2008 city data referenced at page 3.13.1 of the Draft Initial Study/Mitigated Negative Declaration (IS/MND) prepared by the authors of the IS/MND for the Commission. Project background and specifics of the proposed project are from PG&E's application as well as the Draft IS/MND).
3 See IS/MND at 2-28.
