IV. Purpose and Need
SDG&E proposes to expand the existing substation to 56 MVA ultimate capacity for two reasons: (1) to eliminate a 19% overload on the existing single bank substation due to normal area load growth and the new Pala Casino recently completed by the Pala Band of Mission Indians;1 and, (2) to replace the existing 43-year-old substation equipment with newer and more reliable equipment.
SDG&E states that the 1999 peak load for Pala Substation was 9.9 MVA. The forecast peak load is 13.2 MVA in 2001, including area load growth and an additional 2 MVA for the Pala Casino. The existing transformer is 43 years old and is rated at 9.4 MVA for normal operation and 11.1 MVA for planned load limit operation. SDG&E maintains that additional overloading of the existing transformer will significantly decrease reliability. According to SDG&E, the expansion cannot be accomplished within the existing footprint of the station. In addition to replacing the transformer, the 12-kV circuit breakers would have to be replaced to accommodate the increase in fault duty. SDG&E contends that the new equipment must be installed before removal of the existing equipment to prevent interruption of service.
SDG&E states that this project also provides for the eventual expansion of new distribution circuits to supply future load growth in the Pala and San Luis Rey Valley areas. A new 12-kV circuit into the San Luis Rey Valley is planned for the future because the existing 12-kV bus cannot be expanded to accommodate any new circuits.
1 SDG&E is managing this summer's peak (2001), which is expected to be 2.2 MW over the maximum capability of the existing transformer by temporarily offloading some of the Pala load to another substation, and by having the casino's emergency generation on standby mode.
