Michigan’s Upper Peninsula and Northern Wisconsin
Zone 2

Transmission system characteristics of Zone 2

ATC delivers power in Zone 2 with various transmission facilities including:

  • Morgan-Plains and Plains-Dead River 345-kV lines,
  • Plains-Stiles 138-kV double-circuit line
  • Lakota Road-Plains 138-kV line, and
  • 138-kV facilities tying the Upper Peninsula of Michigan to the Lower Michigan.
Transmission system limitations in Zone 2

There are a number of transmission system performance issues in Zone 2 including limited ability to import or export power, generator instability, overloaded lines and equipment, low system voltages and chronic limitations to transmission service. Primary drivers of these issues include a mismatch of load to generation in the Upper Peninsula and aging facilities in poor or obsolete condition. In addition, other studies occurring in parallel with this Assessment, including Northern Area Studies performed by ATC and MISO, have identified several voltage and thermal limitations. The most severe limitations occur during off peak periods.

While not specifically identified in the project list for this assessment, ATC’s capital forecast does include dollars in anticipation of reinforcements needed to address pending generation retirements, such as the White Pines and Presque Isle plants. Potentially, the scope of the project to address the White Pine retirement might include conversion of the 69-kV facilities between the Conover Substation in northern Wisconsin and the Winona Substation in Michigan to 138-kV operation. The potential scope of additional solutions to address the Presque Isle retirement could include a Plains-National project as well as other upgrades in Zones 1 and 4.

Electric system overview

Small increases expected in population, employment – Population in Zone 2 is projected to grow about 0.4 percent annually between now and 2023, and employment is expected to grow about 0.8 percent each year in the same time period. Marquette County, Mich., is projected to realize the largest increase in employment, while Florence County, Wis., is projected to have the highest growth rate.

Electricity usage growing

Zone 2 typically experiences peak electric demand during the winter months. Ore mining and paper mills are the largest electricity users in the zone.

Electric load is forecasted to increase by 0.5 percent annually through 2024. Also, locally generated electricity is declining in the area with smaller, coal-fired generators most at risk. This includes generation owned by industry, municipalities and utilities.

Transmission projects in Zone 2

The most notable planned, proposed and provisional network projects and asset renewal projects in Zone 2, along with their projected year of completion and the factors driving the need for the projects, are listed on the next page.

Zone 2 includes the counties of:
  • Alger , MI
  • Baraga , MI
  • Chippewa , MI
  • Delta , MI
  • Dickinson , MI
  • Florence , WI
  • Forest (N) , WI
  • Gogebic (E) , MI
  • Houghton , MI
  • Iron , MI
  • Keweenaw , MI
  • Luce , MI
  • Mackinac , MI
  • Marinette (N) , WI
  • Marquette , MI
  • Menonminee (N) , MI
  • Ontonagon (E) , MI
  • Schoolcraft , MI
  • Vilas (N) , WI

Zone 2 Planned Projects

Project DescriptionIn-service yearNeed driver
Mackinac 138-kV Substation: Install back-to-back HVDC flow control device2014Address/control flow across eastern U.P., overloads, low voltages
Arnold 345-kV Substation construction and 345/138-kV transformer2015Overloads and low voltages
Bay Lake: Holmes-Old Mead Road 138-kV project2016Overloads and low voltages
Bay Lake: Benson Lake 138-kV Substation - Installation of SVC2019Overloads and low voltages

Zone 2 Proposed Projects

Project DescriptionIn-service yearNeed driver

Zone 2 Provisional Projects

Project DescriptionIn-service yearNeed driver
Victoria-Winona 69-kV line construction2019Overloads, low voltages

Zone 2 Asset Renewal Projects

Project DescriptionIn-service yearNeed driver
Pine River u2013 Hiawatha 69-kV line partial rebuild2015Overloads and low voltage
Munising-Gwinn 69-kV line partial rebuild2017Condition and performance