SAC500 Transmission Project Sacramento Municipal Utility District (SMUD) Western Area Power Administration – Sierra Nevada Region (WASN)

SAC500 Transmission Project

Sacramento Municipal Utility District (SMUD)

Western Area Power Administration – Sierra Nevada Region (WASN)

Feb 2015 - SMUD Board approved agreements to evaluate the feasibility of jointly developing a new 500 kV transmission project with the Western Area Power Administration. The agreements allow initiation of environmental review and to begin regional transmission review activities.

SAC500 Transmission Project

Captain Jack (BPA)

500 kV Existing

230 kV Existing

Legend

Table Mountain (PG&E)

Malin (BPA)

Maxwell (TANC)

Cottonwood (PG&E)

Olinda (Western)

Tesla (PG&E)

Round Mountain (PG&E)

Tracy (TANC)

Hurley

O’Banion (Western)

Elverta (Western)

Elverta

SMUD

Project Overview

•Joint project between SMUD & WASN •Construct ~50 miles, 500 kV transmission line from near Maxwell to near O'Banion & 500/230 kV transformer at O'Banion.

• Configure the new Maxwell switchyard to “double bus, double breaker”

Project Objectives / Benefits:

• Carbon footprint reduction

• Increased flexibility to access low carbon and renewable generation

• Meeting SMUD load serving capability for 2024 and beyond

• Improve system reliability locally and regionally

• Less reliance on SMUD’s thermal generation fleet

• More independence, preserves local decision making

Base Case Assumptions:

• WECC 2024HS • Table Mt. – Rio Oso 230 kV reconductor• Palermo – Rio Oso 230 kV line reconductor• South of Palermo Transmission project, which

consists of reconductoring the southern portion of the Palermo-Rio Oso 115 kV lines #1 & #2 and the Palermo-Pease-Rio Oso 115 kV lines

• DWR RAS unavailable for COI N-S N-2 Contingency

COI Impacts:

Contingency Screen:

• N-1• Credible N-2• Loss of 2 Nuclear Units

COI Impacts:

Study Results:• Provides thermal loading relief on the limiting

elements• Improves reactive power support to the

northern California transmission grid

COI Impacts:

    Contingency / Loading

COI Flow (MW) NCH TMS DLO RM-TM #1 SLO

Pre - Project

4800 70% TM – RIO OSO (111%) RM-TM #2 (99%)

Post - Project

4800 70% TM – RIO OSO (109%) RM-TM #2 (99%)

COI Impacts:

    Reactive Margin (MVAR)

Base Case Contingency ELVERTAS 230

OBANION 230

MALIN 500TABLE MT

500TRACY

500

Pre - Project

2024hs-3353-BASE.sav

CptJ-Olinda-slo-ns

478 479 >1000 >1000 >1000

MPDCI-NS-bipole

551 549 >1000 >1000 >1000

PaloVerde-g2-RAS

389 391 >1000 >1000 >1000

Post – Project

2024hs-3353-MAOB.sav

CptJ-Olinda-slo-ns

812 901 >1000 >1000 >1000

MPDCI-NS-bipole

909 >1000 >1000 >1000 >1000

PaloVerde-g2-RAS

703 780 >1000 >1000 >1000

Other transmission alternatives were evaluated:

Transmission Alternatives:

AlternativeLSC

Increase (MW)

Line Length

(mi)

Loss Savings

(MW)

CVP Flow Reduction

(MW)

Cost Estimate

($M)

1 Maxwell – O’Banion 500kV 364 44 19 295 $250

2 Tracy – SMUD Area 500kV 364 43 21 270 $330

3 Tracy – SMUD Area 230kV 254 43 17 179 <$330

4 Loop Table Mtn. – Tesla into O’Banion 290 < 1 0 331 $77

5 Solano - SMUD 230kV 316 40 2 192 $250

Conclusions:

• More expensive to construct• Unable to meet the project objectives• Requires significant upgrades of existing facilities• Infeasible due to space and zoning concerns

Transmission Alternatives:

• Invitation to WECC members to be part of the SAC500 Project Coordination Review Group

• Contacts:– SMUD: Craig Cameron – (916) 732-5363

[email protected]

Patrick Truong – (916) 732-5267

[email protected]

– WAPA: Kirk Sornborger – (916) 353-4063

[email protected]

WECC Project Review Group:

Supplemental Slides

    Contingency

COI Flow (MW) NCH R. Mtn – Table Mtn TM – VD SLO

Existing System

4800 60% RM – TM (97%)  

4800 70% RM – TM (97%)  

4680 80% RM – TM (99%) Pease-E. Marysville (96%)

4615 90% RM – TM (98%) Pease-E. Marysville (99%)

4373 100% RM – TM (94%) Pease-E. Marysville (99%)

Post-Project 2021 System

4800 60% RM – TM (90%) Pease-E. Marysville (<90%)

4800 70% RM – TM (95%) Pease-E. Marysville (<90%)

4682 80% RM – TM (96%) Pease-E. Marysville (<90%)

4617 90% RM – TM (95%) Pease-E. Marysville (<90%)

4372 100% RM – TM (91%) Pease-E. Marysville (<90%)

MW

BASE MAOB DIFF

COI 4763 4766 3

PACIFIC DC INTERTIE (PDCI) 3100 3100 0

NORTHERN - SOUTHERN CALIFORNIA 3141 3142 1

Bellota-Rancho Seco 230kV: 270.53 199.5 -71.03

Camanch-Rancho Seco 230kV: 265.03 194.33 -70.7

Gold Hill - Lake 230: 167.76 127.06 -40.7

Elverta 230kV Bus Tie: 223.28 188.96 -34.32

Tracy - Hurley #1 230: 257.99 190.77 -67.22

Tracy - Hurley #2 230: 264.01 195.81 -68.2

Folsom - OrangeVale 230: 180.31 155.4 -24.91

Folsom - Lake 230: -68.37 -1.76 -66.61

Maxwell - O’Banion 500:   413.68 413.68

Round MT - COTWD 230 #1: 94.27 86.98 -7.29

Tesla - Tracy 230 #1: 49.62 39.65 -9.97

Tesla - Tracy 230 #2: 49.62 39.65 -9.97

Tracy 500/230 kV Bnk #1 423.45 364.43 -59.02

Tracy 500230 kV Bnk #2 423.45 364.43 -59.02

Keswick - O’Banion 230 #1: 249.9 209.22 -40.68

Keswick - Flanagan 230 #1: -81.81 -81.2 -0.61

Hurley - Procter 230 #1: -159.56 -83.81 -75.75