Abstract
The San Francisco Bay Area has experienced a significant increase in electric demand in the past few years. Maximum demand in the Bay Area has reached 9,100 MW, and even with a slower economy, the electric demand is still expected to grow at a rate of more than 2% per year. To supply the Bay Area's electric demand, Pacific Gas & Electric (PG&E) relies both on its transmission facilities and merchant generation facilities located in the Bay Area. The installation of new generation has not kept up with this growth, thereby imposing significant stress on the transmission system. Continued demand growth is met solely by capacity expansion of PG&E's transmission grid. In addition to needing more transmission lines and transformers, the continued demand growth also increased reactive power consumption. A Flexible Alternating Current Transmission System (FACTS) technology device can offer an economical solution to the maintenance and improvement of the bulk system reliability. Specifically a Static Var Compensator (SVC) could be installed strategically to provide reactive power support. With the proposed decommissioning of Hunters Point Power Plant synchronous condenser units 2 and 3, originally generators 2 and 3, another source of reactive power will be needed. An SVC system at PG&E's Potrero substation will help alleviate a major part of this demand. There are two existing 115 kV capacitor banks at this substation, and with the addition of an SVC the existing capacitor banks would be included in the SVC control to form a Static Var System (SVS). Technical reviews has confirmed that costly upgrades to these aging assets cannot be justified for their remaining life. Technical studies indicate that a fast acting dynamic FACTS device such as an SVC will be the most reliable and economical solution to the reactive power demand in the Bay Area.