Eau Claire Area Study

Northern MAPP Subregional Planning GroupJanuary 11, 2007

Daniel Kline

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Outline

Description of Area Various Load Serving Problems Study Methodology & Initial Alternatives Final Alternatives Final Recommendation Questions

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Description of Area

Located in West-Central Wisconsin Eau Claire & Chippewa Counties About an hour east of Twin Cities on I-94

Area fed by 345 and 161 kV sources and 69 kV transmission

Load belonging to NSPW and DPC

Lines belonging toNSPW and DPC

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Description of Area

Area NSPW Sources: Eau Claire Substation Seven Mile Substation Wheaton Substation Chippewa River Generation

Area DPC Sources (2011): Elk Mound Substation

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Description of Area

Area NSPW Loads (2011): Jeffers Road (27 MW) Truax (41 MW) Otter Creek (35 MW) London (42 MW) Hallie (31 MW)

Area DPC Loads (2011): Seymour (4 MW) Elco (4 MW) Equity (3 MW) Washington (3 MW) Brunswick (2 MW)

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Description of Area

To WPL ArpinTo NSPW King

Presto

NSPW US Rubber

NSPW Hallie

NSPW Chippewa Falls NSPW Wissota

To NSPW Jim Falls

NSPW Otter Creek

NSPWSevenMile

NSPW Tremval

NSPW EllisNSPW Shawtown

NSPW Truax

NSPW Dells

NSPW Madison Street

To NSPW Red Cedar

NSPWEau Claire

DPC Elk Mound

To NSPW Red Cedar

NSPW Hydro Lane

To NSPW T-Corners

NSPW Jeffers Road

NSPW Wheaton

To NSPW Cotton School

DPC Seymour

DPC Ludington

To Xcel Jim Falls

DPC Barron

To DPC Alma

DPC Union

DPC Brunswick DPC Washington DPC Equity

To NSPW Red Wing

& DPC Alma

NSPW London

DPC Elco

NSPW Sterling

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Description of Problems Eau Claire transmission system is

designed to rely upon Eau Claire 69 kV bus Eau Claire 161/69 kV transformers are

heavily loaded and cannot endure loss of parallel bank

Eau Claire substation is crowded and not enough space exists to increase the size of the existing 161/69 kV banks

Increasing size of banks would require moving to non-standard bank sizes

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Description of Problems

During peak load conditions, 69 kV system to north overloads

DPC system served out of Seven Mile overloads for various contingencies

High load growth throughout area Interconnection requests at Hallie Substation

requrie auto-transfer scheme to be turned off Area transmission system highly susceptible to

fluctuations in Chippewa River generation

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Study Methodology

2006 MAPP Series Cases 2011 Near-Term 2016 Out-Year

Worked with DPC through Joint Planning Process

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Study Methodology

Assumptions and Adjustments made Assumed Chisago Line Project not in service in

2011 (In-service in 2016) Included New Richmond Area Load Serving

Study projects Assumed Monroe County – Council Creek 161

kV line in service in 2011 Moved Riverview load to Hallie

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Study Methodology

Bus Name ContVolt BaseVolt Contin.Description

Shawtown 69 kV 0.8736 1.0151 Eau Claire - Dells - Sterling 69 kV Line

Folsom 69 kV 0.8699 1.0218 Eau Claire - Dells - Sterling 69 kV Line

Madison St. 69 kV 0.8700 1.0209 Eau Claire - Dells - Sterling 69 kV Line

Sterling 69 kV 0.8697 1.0234 Eau Claire - Dells - Sterling 69 kV Line

Shawtown 69 kV 0.8920 1.0151 Eau Claire - Sterling - Madison St. 69 kV Line

Madison St. 69 kV 0.8894 1.0209 Eau Claire - Sterling - Madison St. 69 kV Line

London 69 kV 0.8994 1.0040 Eau Claire - Sterling - Madison St. 69 kV Line

Washington 69 kV 0.9064 1.0029 Eau Claire - Sterling - Madison St. 69 kV Line

Equity 69 kV 0.9354 1.0056 Eau Claire - Sterling - Madison St. 69 kV Line

Eagle Point 115 kV 1.0501 1.0425 Hydro Lane - Wissota 115 kV Line

Hydro Lane 115 kV 1.0516 1.0437 Hydro Lane - Wissota 115 kV Line

Chippewa Falls 115 kV 1.0501 1.0425 Hydro Lane - Wissota 115 kV Line

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Study Methodology

Base Case Results Base Case Results

Affected Facility ContMVA Loading% Contingency

Eau Claire 161/69 kV Transformer 113.4 101.2 Eau Claire - Arpin 345 kV Line

Independence to Elk Creek 69 kV Line 26.3 105.1 Eau Claire - Arpin 345 kV Line

Seven Mile to Elco 69 kV Line 91.1 193.8 Eau Claire - Dells - Sterling 69 kV Line

London to London Tap 69 kV Line 79.9 111.0 Eau Claire - Dells - Sterling 69 kV Line

London Tap to Equity 69 kV Line 83.7 178.1 Eau Claire - Dells - Sterling 69 kV Line

Elco to Equity 69 kV Line 86.5 184.0 Eau Claire - Dells - Sterling 69 kV Line

Seven Mile to Elco 69 kV Line 82.2 175.0 Eau Claire - Sterling - Madison St. 69 kV Line

London Tap to Equity 69 kV Line 74.9 159.5 Eau Claire - Sterling - Madison St. 69 kV Line

Elco to Equity 69 kV Line 77.7 165.3 Eau Claire - Sterling - Madison St. 69 kV Line

Independence to Elk Creek 69 kV Line 25.9 103.5 Hydro Lane - T-Corners 115 kV Line

Independence to Elk Creek 69 kV Line 25.7 103.0 Hydro Lane - J im Falls 115 kV Line

Eau Claire 161/69 kV Transformer 116.6 104.1 Eau Claire - Jeffers Road 161 kV Line

Independence to Elk Creek 69 kV Line 25.6 102.2 Eau Claire - Jeffers Road 161 kV Line

Eau Claire 161/69 kV Transformer 117.1 104.6 Eau Claire - Seven Mile 161 kV Line

Eau Claire 161/69 kV Transformer 113.6 101.5 Wheaton - Jeffers Road 161 kV Line

Eau Claire 161/69 kV Transformer 144.8 129.3 Eau Claire 161/69 kV Transformer

Eau Claire 161/69 kV Transformers 121.0 108.0Chippewa River Generation & Hydro Lane - Red Cedar 161 kV Line

Remaining Eau Claire - Chippewa Falls 69 kV Line 90 to 106 105 to 123

Low Chippewa River Generation & Eau Claire - Chippewa Falls 69 kV Line

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Initial Ideas

Reconductor double-circuit 69 kV corridor between Eau Claire and Chippewa Falls

Convert 69 kV double-circuit corridor to 161 kV

Add circuit breakers at Otter Creek Shift load from 69 kV system to 161 kV

system

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Final Alternatives

Alternative 1 Convert entire 69 kV corridor from Eau Claire to

Chippewa Falls to 161 kV Convert all 69 kV load along corridor to 161 kV operation

Alternative 2 Extend 161 kV from Presto Tap to Hallie Substation Place US Rubber on loop from Eau Claire Substation Place Chippewa Falls on loop from Wissota Substation

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Final Alternatives

Alternative 3 Convert double-circuit 69 kV corridor to single-

circuit 161 kV Convert Hallie to 161 kV operation Place US Rubber on loop from Eau Claire

Substation

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Final Recommendation

Alternative 3 Recommended Reterminate Wheaton to Presto Tap 161 kV line at Eau

Claire Substation Tear down existing 69 kV double-circuit line between Eau

Claire and the point where line intersects with Hydro Lane – Red Cedar 161 kV line

Construct 161/69 kV substation (50th Avenue Substation) where double-circuit 69 kV line intersects Hydro Lane – Red Cedar 161 kV line

Construct single circuit 161 kV line from Eau Claire to 50th Avenue Substation

Convert Hallie Substation to 161 kV operation

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Final Recommendation

To WPL ArpinTo NSPW King

Presto

NSPW US Rubber

NSPW Hallie

NSPW Chippewa Falls NSPW Wissota

To NSPW Jim Falls

NSPWOtter Creek

NSPWSevenMile

NSPW Tremval

NSPW EllisNSPW Shawtown

NSPW Truax

NSPW Dells

NSPW Madison Street

To NSPW Red Cedar

NSPWEau Claire

DPC Elk Mound

To NSPW Red Cedar

NSPW Hydro Lane

To NSPW T-Corners

NSPW JeffersRoad

NSPW Wheaton

To NSPW Cotton School

DPC Seymour DPC Ludington

To Xcel Jim Falls

DPC Barron

To DPC Alma

DPC Union

DPC Brunswick DPC Washington DPC Equity

To NSPW Red Wing

& DPC Alma

NSPW London

DPC Elco

NSPW Sterling

NSPW 50th Avenue(Proposed)

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Final Recommendation

Very robust service provided to area north of Eau Claire

Off-loading of Eau Claire 161/69 kV transformers buys approx. 12 years of life expectancy

Strong corridor to support Chippewa River generation

Increased Load-serving north of Jim Falls

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Next Steps

Funding requested for 2007 budget process

Continuing to investigate ways to off-load 69 kV network out of Eau Claire

Eau Claire Area Long-Term Study to be completed with DPC during Summer 2007