Western Electricity Coordinating Council

MIC Meeting – Liaison ReportOct 24, 2006 – Salt Lake City

Operating Transfer Capability Policy Committee

(OTCPC)

October 27, 2006 MIC Liaison Report 2

Contents

Who, What, When, and Why of the OTCPC

Performance Review (COI)

Study Results

Recent Discussion Items

MIC Discussion

October 27, 2006 MIC Liaison Report 3

Who, What, When, Why of the OTCPC

1/4Purpose:

Formed by Board 8/11/98 in response to 7/2/96, 8/10/96 – lessons learned, won’t operate at unstudied OTC level

Provide coordinated, standard development, determination of OTCs throughout WECC

Forum for communications, assure consistent study methodologies

Provide highest OTCs consistent with reliable operation of WECC grid

Duties:

Approve/disapprove seasonal OTC limits studied by the four Subregional Study Groups: NW Operational SG, Rocky Mtn SG, SW Area SG, Ops Study Subcom

Determine which transmission paths are to be studied

Ensure that the subregional studies are held to the same standards, level of work required and study methodologies

Facilitate OTC dispute resolution

Recommend policy positions to the Board (e.g. from disturbance reports – Open Loop Operation, PSCO – “perceived transmission constraints”)

October 27, 2006 MIC Liaison Report 4

Who, What, When, Why of the OTCPC

2/4Functions:

Review and approve Subregional seasonal study plans and technical simulation results.

Develop policies and procedures addressing seasonal OTC’s

CMOPS OPRG reviews/approves operating procedures for each season

Establish work groups such as Subregional Study Groups and Operating Procedures Review Group.

CA-NX: Mark Willis (SMUD), Rocky Mtn: Brent Vossler (WACM), Northwest: John Phillips (PSE), AZ-NM: Tom Isham (APS)

Address OTC seams issues between subregions.

Provide technical guidance.

For Further OTCPC Consideration:

Need for OTC studies beyond most critical N-1 or N-2 outages?

What combinations of line outages, generation patterns or outages, reserves topography or load conditions require OTC reduction – FRR

October 27, 2006 MIC Liaison Report 5

Who, What, When, Why of the OTCPC

3/4Membership:

9 Voting Members – 3 year terms (staggered)

3 Directors or high level management appointed by WECC Board –

Chair (Vickie VanZandt, BPA) from this group (exp 04, 2007)

Others: Dick Ferreria exp 4/07, TANC and Mike Risan, Basin Electric exp 4/08

6 are from OC/PC/MIC - 2 each, with a TC and TP class member

OC: Duncan Brown, Calpine exp 4/07 TC and Mike Flores, Tucson exp 4/07 TP

PCC: Hardev Juj, Seattle exp 4/07 TC and James Leigh Kendall, SMUD exp 4/08 TP

MIC: Edison Elijah, PacifiCorp exp 4/09 TC and R Buckingham, PG&E exp 4/09 TP

Standing Committee Chairs coordinate selection with OTCPC Chair and consider – in priority order:

Technical expertise

Regional diversity

Member class diversity

October 27, 2006 MIC Liaison Report 6

Who, What, When, Why of the OTCPC

4/4Path Study Criteria (What is subject to OTCPC Review)

Annually review paths and study conditions (by Subregional Study Groups)

Comprehensive studies (Var margin, RAS compliance, Nomogram transition points) required (path owners and operators responsibility):

Actual outage and CMOPS report finds a deficiency in the operating study

Path or system changes that affect OTC by 5% or more

Study criteria or processes change impact OTC by 5% or more

A new or previously not studied (using current criteria) path is determined to have possible significant interconnection wide impact

A change in OTC for a path or a new OTC for the path is proposed

Check cases ok (worst contingencies only) if no major changes and at least one year or two like seasons studied comprehensively in last 5 years

Removal from study (but subject to confirmation every 3 years) if:

No interaction with other paths (only impacts the local area);

No more than 5% change in OTC over 2 years (in like seasons);

OTC not affected by seasonal loads and dispatch

OTCPC and Subregional Discretion (may add or remove paths outside of above criteria)

October 27, 2006 MIC Liaison Report 7

Summer 2006 Review1/6

Critical Outage Events

RAS, 500/345-kV N-1, N-2, G-2

OTCact vs OTCmax and Actual flow on Key Studied Paths

Path 66 Path 26 SCIT PDCI NJD

October 27, 2006 MIC Liaison Report 8

July 2006 COI Performance Review2/6

COI (CAL-OR INTERTIE): 01JUL06 - 31JUL06ACTUAL LOADINGS and CAPACITIES, BY HOUR

-4500

-4000

-3500

-3000

-2500

-2000

-1500

-1000

-500

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Date

MW

H (

load

ings

) M

W (

capac

itie

s)

COI ACTUAL NW AC CAPACITY: N to S (Scheduling Limit) NW AC CAPACITY: S to N (Scheduling Limit) LOOP FLOW at MALIN

S-to-N

N-to-S

4800 --

-3675 --

October 27, 2006 MIC Liaison Report 9

August 2006 COI Performance Review3/6

COI (CAL-OR INTERTIE): 01AUG06 - 31AUG06ACTUAL LOADINGS and CAPACITIES, BY HOUR

-4500

-4000

-3500

-3000

-2500

-2000

-1500

-1000

-500

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Date

MW

H (

load

ings

) M

W (

capac

itie

s)

COI ACTUAL NW AC CAPACITY: N to S (Scheduling Limit) NW AC CAPACITY: S to N (Scheduling Limit) LOOP FLOW at MALIN

S-to-N

N-to-S

4800 --

-3675 --

October 27, 2006 MIC Liaison Report 10

September 2006 COI Performance Review4/6

COI (CAL-OR INTERTIE): 01SEP06 - 30SEP06ACTUAL LOADINGS and CAPACITIES, BY HOUR

-4500

-4000

-3500

-3000

-2500

-2000

-1500

-1000

-500

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Date

MW

H (

load

ings

) M

W (

capac

itie

s)

COI ACTUAL NW AC CAPACITY: N to S (Scheduling Limit) NW AC CAPACITY: S to N (Scheduling Limit) LOOP FLOW at MALIN

S-to-N

N-to-S

4800 --

-3675 --

October 27, 2006 MIC Liaison Report 11

Spring 2004 COI Performance Review5/6

COI Actual and Available - 2004 January-May

-1000

0

1000

2000

3000

4000

Date/Time

Megawatts

October 27, 2006 MIC Liaison Report 12

Spring 2004 COI Performance Review6/6

COI (CAL-OR INTERTIE): 01MAY04 - 31MAY04ACTUAL LOADINGS and CAPACITIES, BY HOUR

-4500

-4000-3500

-3000

-2500-2000

-1500-1000

-500

0500

1000

15002000

25003000

3500

40004500

5000

Date

MW

H (

load

ings

)

MW

(ca

paci

ties

)

COI ACTUAL (380002) NW AC CAPACITY: N to S (Scheduling Limit) (598995)

NW AC CAPACITY: S to N (Scheduling Limit) (598997) LOOP FLOW at MALIN (599980)

Rated capacities labeled as 4800 (N-S) and -3675 (S-N), capacity availability = actual capacity/rated capacity, capacity utilization = actual loading/actual capacityActuals may exceed scheduling limit as long as conditions remain within North-of-John-Day vs. COI & PDCI operating nomogram limits

Actuals: "COI"=AC INTERTIE going to California (excludes Reno-Alturas). Capacity: "NW AC CAPACITY" is capacity on NW portion of AC Intertie

S-to-N

N-to-S

4800 --

-3675 --

October 27, 2006 MIC Liaison Report 13

Study Results1/4

Path Direction Rating Sum 06 Sum 05 Sum 03

COI+NW-Sierra (66) South 4800 4800* 4800 4800 Added generation in North CA affects Nomogram/Up to 300 MW to Sierra

PDCI-n and PDCI-s (65) South 3100 3100* 3100 3100 PDCI converter valve replacement project completed early 2005

Midway-Los Banos (15) North 5400 5400 5400 3950 Path 15 Upgrade project in-service 12/2004, shifts RAS to protect for flows

North of Los Banos, RAS uses balanced load and gen, only arms as neededSCIT (All ties into So. CA) West 18,860 15,600* 14,80015,200

800 MW increase due to series cap replacement, added VAR supportCOI+NW+PDCI (N/A) South 7900 7900 7900 7900North of John Day (73) South NR 7800* 7700 7700

Schultz-Watoma addition 12/2005

* OTC studies performed

October 27, 2006 MIC Liaison Report 14

Study Results2/4

Path Direction Rating Sum 06 Sum 05 Sum 03

Midway-Vincent (26) South 4000 4000* 4000 3000 RAS supports OTC increases to 3400, 3700, and 4000 (SCE drops

load only for flow levels above 3700 MW, gen drop used first) Path 26 takes reductions for simultaneous interactions at COI or EOR

Brownlee East (55) East 1850 1850 1750 1750 Addition of #2 Brownlee-Oxbow 230-kV line, 93 MVar 2004

South of Allston (N/A) South NR 3090* 2640 2700 Increase based on generation dispatch assumptions

West of Hatwai (6) West 4277 4065* 3960 26-800

Sierra-Utah (32) West 440 370 370 240 Falcon-Gonder 345-kV line addition 2004

Bridger West (19) West 2200 2200 2200 2200

* OTC studies performed

October 27, 2006 MIC Liaison Report 15

Study Results3/4

Path Rating Sum 06 Sum 05 Sum 03

Borah West (17) West 2307 2307 2307 2100

Montana-NW (8) West 2200 2200* 2200 2200

Midpt-Summer Lake (75) East 400 400 400 400 In rating process since before 1996, Eastbound flows directly affect

COI Idaho-NW (14) East 1200 1090 1090

Path 14 OTC limited to amount at which Path 75 flow reaches rated OTC

TOT 2A 690 690 690 650 New procedure expanded area where load was varied

TOT 3 1605 1590 1594 1579 Path is thermally limited, OTC varies slightly each year

OTC studies performed

October 27, 2006 MIC Liaison Report 16

Study Results4/4

Path Rating Sum 06 Sum 05Sum 03

Four Corners-West (22) 2325 2325 2325

Cholla-Pinnacle Peak (50) 1200 1200 1200 1200 These AZ-NM paths are studied summer only, thermally limited,

Southern New Mexico (47) 1048 1048 1048 1048

Northern New Mexico (48) 1947 1947 1947 1450-1692 Norton-Hernandez facility upgraded in 2004 Paths 47, 48 are post-transient limited, operated at maximum OTC

based on monitored system conditions and limited to studied amounts

East of River (49) 7550 7550 7550

October 27, 2006 MIC Liaison Report 17

OTCPC – Recent Discussion Items1/2

OTCPC Open Loop Operating Limits and Need for South to North OTCs for TOT2

Determination of south to north operating limits for TOT2, TOT2A, B, C, under Open Loop conditions to meet G-1 criteria needed. OTCPC reviewed the need to have a South to North OTC to give a safe operating point in the event that flows go South to North. Such a study process would need PAC and Sierra-Nevada to be involved. Rocky Mountain Study Group and Northwest study will coordinate to develop a study process.

Standards of Conduct Question – Availability of Study Center Work Products

OTCPC and Regional Subgroups meeting attendees have early transmission sensitive information – Propose to post preliminary study results on WECC website at time of Regional Subgroup internal distribution.

Use of Seasonal OTC at higher limit while project in Phase 2

Use of higher OTC requires that responsible party is known for reductions dictated by nomogram relationships. Other criteria: Facilities in service, WECC Project Review group do not object, Must becritical load serving need verified by reliability authority.

October 27, 2006 MIC Liaison Report 18

OTCPC – Recent Discussion Items 2/2

Need procedures to resolve Tot 1A, Bonanza West, Path 33, interactions

Deseret has possible issues on operating procedure implementation related to OTC violations. Operators have had difficulties controlling flow. Failure to arm unit tripping can also cause OTC violations. Reliability Coordinators also need to be made aware of the appropriate actions to mitigate OTC violations.

Findings of 2/18/06 PSCO Disturbance Report

Additional power was available, but not scheduled due to perceived transmission constraints. Need to assess ability to use of “counterflow” ATC in emergency events.

October 27, 2006 MIC Liaison Report 19

MIC Discussion

MIC Interests – Review of Paths with ATC or other Commercial Issues?

Performance – Review of OTC Reductions and Reasons?

Possible action item to review scheduling practices – counterscheduling.

Others?

October 27, 2006 MIC Liaison Report 20

Future OTCPC Steps

For follow-up:

Review alternatives for addressing affects of new models on operating transfer capability limits in an effort to avoid having to reduce operating transfer capability limits to maintain reliability and comply with established criteria. – Mark Maher/Bob Dintelman RPIC 2/12/2004

Action Item: This RPIC task force will expand its scope to identify aspects of processes that are broken or can be improved. The original scope was to identify solutions that provide similar reliability without reductions in OTCs.