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
- Conover-Plains 138-kV line, and
- 138-kV facilities tying the Upper Peninsula of Michigan to the Lower Peninsula.
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.
Transmission system limitations in Zone 2
In the analysis of Zone 2, we identified low voltages, high voltages, transmission facility overloads and transmission service limitations. 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.
Electric System Overview
Small increases expected in population, employment – Population in Zone 2 is projected to grow about 0.2 percent annually between now and 2021, and employment is expected to grow about 1.0 percent each year in the same time period. Marquette County, Mich., is projected to realize the largest increase in employment, while Houghton County 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 projected to increase by 0.35 percent annually through 2021. 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
We have implemented three network projects in Zone 2 since the 2011 Assessment, including installing a second 138/69‑kV transformer and a 138‑kV ring bus at the Chandler Substation.
Our current plans in Zone 2 include 20 system reliability and economic projects between 2012 and 2026, three of which are related to our new Study-Based Rating Methodology. These projects are in various stages of development. The most notable planned, proposed, provisional 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.
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 Description | In-service year | Need driver |
|---|---|---|
| Atlantic-M38 69-kV line rebuild | 2013 | Overloads, low voltages, condition and performance |
| Straits-Pine River 69‑kV double circuit rebuild | 2014 | Overloads and low voltages |
| Mackinac 138‑kV Substation; Installation of back-to-back HVDC flow control device | 2014 | Address/control flow across eastern U.P., overloads and low voltages |
Zone 2 Proposed Projects
| Project Description | In-service year | Need driver |
|---|---|---|
| Chandler-Old Mead Road 138‑kV double circuit lines | 2014 | Overloads and low voltages |
| Arnold 345‑kV Substation construction and 345/138‑kV transformer | 2014 | Overloads and low voltages |
| Bay Lake: Green Bay-Morgan-Plains-National 345‑kV line construction | 2016-2018 | Overloads and low voltages |
| Bay Lake: Holmes-Escanaba 138‑kV project | 2016-2018 | Overloads and low voltages |
Zone 2 Provisional Projects
| Project Description | In-service year | Need driver |
|---|---|---|
| Seney-Blaney Park 69‑kV line uprate | 2015 | Overloads, low voltages, condition and performance |
Zone 2 Asset Renewal Projects
| Project Description | In-service year | Need driver |
|---|---|---|
| Nine Mile-Roberts 69-kV line partial rebuild | 2012 | Condition and performance |
| Munising-Gwinn 69-kV line partial rebuild | 2012-2013 | Condition and performance |
| Rexton-Hiawatha 69-kV line partial rebuild | 2015 | Condition and performance |
| Conover-Mass 69-kV line partial rebuild | 2018 | Condition and performance |
| Powers-Chalk Hill 69-kV line partial rebuild | 2018 | Condition and performance |
| Straits-McGulpin 138-kV submarine cable replacements | 2020 | Condition and performance |