Path Rating Catalog 2013 - Western Electricity Coordinating Council

71. South of Allston
Revised January 2013
Accepted Rating
Existing Rating
Other
Location:
Definition:
Transfer Limit:
Critical
Disturbance
that limits the
transfer
capability:
When:
System
Conditions:
Study Criteria:
Remedial
Actions
Required:
Formal
Operating
Procedure:
Allocation:
Interaction
w/Other
Transfer Paths:
Southwestern Washington/Northwestern Oregon
Sum of the flows on the following lines:
Line Owner Metered End
Clatsop 230/115 kV BPA Clatsop
Allston-Keeler 500 kV BPA Allston
Allston-Rainier 115 kV BPA Allston
Astoria Tap-Seaside 115 kV PAC Astoria Tap
Merwin-View 115 kV PAC Merwin
Trojan-Rivergate 230 kV PGE Trojan
Trojan-St Marys 230 kV PGE Trojan
Woodland Tap-Ross 230 kV BPA Ross
Currently, per DSO 309, the SOL in the north to south direction is a dynamic
limit and varies between 2935 and 3980 MW.
The SOL in the south to north direction is a dynamic limit that adjusts in real
time and the limit is 1115 MW.
Allston-Keeler 500 kV line
Keeler-Pearl 500 kV line
Trojan-Rivergate 230 kV and Trojan-St Marys 230 kV line
Allston-Trojan #1 and #2 230 kV lines
Trojan –St Marys 230 kV and St Marys-Keeler 230 kV lines
The path is limited for outages that cause thermal overloads
SOL studies are completed on an annual basis.
Heavy summer loadings
Canada - NW – high north to south flow
California - Oregon Intertie – high north to south flow
Pacific DC Intertie – high north to south flow
Upper Columbia generation high
Lower Columbia generation low
I-5 Corridor generation high
BPA, PGE, PAC and WECC/NERC
Generation dropping on available I-5 corridor thermal generation (Chehalis,
Big Hanaford, and Fredrickson. Grays Harbor, Mint Farm, and Beaver)
Generation ramping on Lewis River (Swift and Yale)
Generation dropping in B.C. Hydro
Generation dropping on Upper Columbia (Coulee and Chief Joseph)
BPA Dispatcher Standing Order No. 309 (updated seasonally)
All of the Capacity is allocated to BPA, PAC and PGE.
None
PART VI Item 1-181