1.1 Bay Area

TYPE OF CONSTRAINTS

_ Reliability Must Run (RMR)

¬ Problem

_ With all generators available, there is not an overall RMR reliability constraint. However, with a generation unit out, there is a need to import power into bay area.

¬ Solution:

_ Increase capacity into bay area.

¬ Projects:

_ Tesla-Newark Transmission Reinforcement Project (T670).

_ Stability

¬ Problem:

_ Voltage Support

¬ Solution:

_ Shunt Capacitors

¬ Projects:

_ Metcalf 500 kV Shunt Capacitor Project (T519)

_ Martin 115 kV Shunt Capacitor Project (T636)

_ Tesla-Newark Transmission Reinforcement Project (T670 - Needed for both capacity and voltage stability.)

¬ What happens if problem is not fixed:

_ Customers would be dropped if voltage reaches a preset value and there could be system stability problems.

_ Normal Overloads

¬ Problem:

_ Normal transformer and/or line overload.

¬ Solution:

_ Reconductor and re-rate transmission lines and transformers to increase normal capacity.

¬ Projects

_ Tesla-Newark 230 kV line-Add 2^nd circuit (T670).

_ Ravenswood 230 kV loop (T498) and 230/115 kV Transformer Capacity Increase (T476).

_ Lakewood Area 115 kV (T546).

_ Pittsburg-Tassajara 230 kV Reconductoring (T552).

_ Mt View-Whisman Transformer re-rate (T671).

_ Ravenswood-Ames 115 kV Re-rate (T498).

_ Coyote Valley Interconnect (T579).

_ Nortech (Kifer-Trimble) 115 kV loop (T010).

_ Moss Landing 115 kV Circuit Breaker Upgrade (T668).

_ Moss Landing 500/230 kV Transformer Rating Increase (T674).

_ Newark 230/115 kV Bank TCAP Project (T239).

¬ Projects (cont'd)

_ Jefferson 230/60 kV Bank Re-rate (T240).

_ Contingency (Outage)

¬ Problem :

_ Transformer and/or line overloads under certain N-1 outages.

¬ Solution:

_ Reconfigure transformer and/or line configurations.

¬ Project:

_ Grant-East Shore 115 kV Breaker Project (T667).

_ Lakewood Area Transmission Reinforcement Project (T546).

_ Metcalf-Monte Vista 230 kV Line Project (T647).

DESCRIPTION

The Greater Bay Area is essentially located at the center of PG&E's service territory. This area primarily consists of Alameda, Contra Costa, San Mateo, and San Francisco Counties. It is also host to municipal agencies such as City of Alameda, City of Palo Alto, and City of Santa Clara.

Electric load is served by a combination of power produced by local generation and power imported over the transmission system. The transmission system consists primarily of four major outlying 500/230kV substations (PG&E's Vaca-Dixon, Tesla, and Metcalf substations, and WAPA's Tracy substation) and a network of 230kV import circuits.

This area currently has about 4800MW of internal generation, from steam turbines, combustion turbines, self-generation, and "Regulatory Must Take" QFs. The Greater Bay Area is highly dependent on transmission imports (about 4300MW) to serve its load. The summer peak load is about 9100MW. Projected load growth in the area for the next few years is about 150MW to 250MW per year on average.