POSSIBLE SOLUTIONS

1. The ISO could solicit more RMR in the Eagle Rock area to eliminate the potential low voltage problem caused by the outage of Cortina 230/115/60 kV transformer.

2. PG&E could re-conductor two sections of Fulton #1 60 kV line (Project No. T-490). The project T-490 addresses a local Emergency overloading problem of the Fulton #1 60 kV line during the line outage contingency within the North Bay area. With this transmission line project completed in 2001, the Normal and Emergency (N-1 contingency) overloading problem of the Fulton #1 60 kV line can be solved.

1.8 Battle Creek

TYPE OF CONSTRAINTS

_ Economic (Bulk)

_ Reliability Must Run (RMR)

_ Stability:

_ Normal Overload

_ Contingency (Outage)

RECOMMENDATION

DESCRIPTION

The Battle Creek Area covers the north central portion of Tehama County and the south central portion of Shasta County. The Battle Creek Area is located east and south of Redding, and includes the cities of Red Bluff, Los Molinos, and Whitmore.

The major transmission sources serving this area are the Cascade-Benton-Deschutes 60kV line in the north with a normal maximum 29 MVA and emergency 34 MVA capacity and one 168 MVA 230/60kV transformer at Cottonwood in the west. This area has a summer peak load of approximately 139 MW. Projected load growth for this area is about 1 MW from 2001 to 2002 and 2 MW from 2002 to 2003. Therefore, the import capability is enough to serve the regional loads under Normal conditions.

This area has about 43 MW of internal generation from 9 hydro generators. QFs can provide about another 13 MW.

PROBLEMS

The Battle Creek assessment did not find any normal voltage or thermal problems within the 2001-2005 time frame. It did, however, identify two emergency thermal problems due to single-contingencies.

The loss of the Cottonwood 168 MVA 230/60kV transformer could result in unacceptable overloading of the Cascade-Loomis Junction section of the Cascade-Benton-Deschutes 60 kV line, which might result in low voltage and possible voltage collapse in the Red Bluff area.

POSSIBLE SOLUTIONS

To solve the transformer outage contingency, RMR is needed in this area. Unfortunately, 102 MW of RMR is needed for year 2001 whereas the total nameplate of RMR candidates is only 43 MW.

There are no firm plans at this time for additional transmission reinforcements in the Battle Creek Area.

CPUC recommends the following:

· Solicit more QF facilities in this area

· PG&E to conduct an economic analysis on installing a back up transformer in this area

Section 2 - TRANSMISSION CONSTRAINTS ON SCE's SYSTEM

TYPE OF CONSTRAINTS

SCE's electric transmission system is facing no major constraint, but a number of localized constraints in the coming years:

· Antelope-Bailey 66kV reliability constraint

· Midway-Vincent Path 26 economic constraint

· Alamitos-Barre #2 230kV line reliability constraint

PHYSICAL DESCRIPTION

SCE's transmission system service territory is located in Southern California, South of PG&E, but North of SDG&E and IID, not including LADWP. For 2001, its load is forecasted at 21,450MW using 1-in-10 years method. SCE system, together with LADWP system, is a fairly strong system with multiple 500kV transmission ties to the Southwest and DC tie to the Northwest.

PROBLEMS

Path 26, SCE's interface with its Northern neighbor, PG&E, consists of three 500kV transmission line. This path enables hydro power to flow from North to South during the spring, thermal power from South to flow to North during winter. Congestion happens fairly often on the path and cost more than $10 million this year.

Antelope-Bailey 66kV system is an isolated packet of SCE system. This 66kV system has large amount of wind generation and some hydro. In spring season, voltage problem happens frequently.

Victorville-Lugo 500kV line reliability constraint happens only when there is a simultaneous double line outage (N-2). N-2 contingency is an unlikely event, beyond the requirement of WSCC and ISO planning criteria.

Alamitos-Barre #2 230kV line reliability constraint is a local reliability problem with little overall system impact.

SOLUTIONS

The wavetraps replacement on the Midway-Vincent #3 500kv line project will relieve the congestion on Path 26, reduce congestion cost by about $5 million.

The Antelope-Bailey 66kV system rearrangement project will improve voltage profile for the area.

The Alamitos-Barre #2 230kV line wavetraps replacement projects will increase ratings on these lines, thus eliminate the overload problems.

SCE transmission system will be able to adequately serve its forecasted 2001 load. However, uncertainty exists on the availability of surplus generation resources outside SCE territory, which SCE has little control.

Section 3 - TRANSMISSION CONSTRAINTS ON SDG&E's SYSTEM

TYPE OF CONSTRAINTS

SDG&E's electric transmission system is facing a major import constraint besides localized constraints in the coming years:

· SDG&E import capability constraint

· Escondido Substation reliability constraint

· Rancho Santa Fe Substation reliability constraint

PHYSICAL DESCRIPTION

SDG&E system is a semi-isolated system connected with outside system only through:

· 500kV Southwest Power Link (SWPL) that runs from Palo Verde to Miguel, is SDG&E's connection to Southwest and CFE in Mexico

· Five 230kV lines that make up South of SONGS, is SDG&E's connection to SCE

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