Southeast Wisconsin Zone 5

Transmission system limitations in Zone 5

A significant transmission system performance challenge in Zone 5 involves heavy energy market flows through the zone, resulting in potential high post-contingency line loadings.

Electric system overview

Increases expected in population, employment

Population in Zone 5 is projected to grow 0.3 percent annually between now and 2028, and employment is projected to grow 0.9 percent in the same time period. Waukesha County is projected to realize the largest increase in total population and Milwaukee County is projected to realize the largest increase in total employment. Washington County is projected to have the highest annual growth rate in population while Kenosha County is projected to have the highest annual growth rate in employment of 0.6% and 1.7%, respectively.

Electricity usage

Peak electric demand typically occurs during the summer months. Large industrial loads in the Milwaukee metropolitan area are among the largest electricity users in the zone.

Electric load is forecasted to grow approximately 0.7 percent annually through 2029.

Transmission projects in Zone 5

The most notable planned, proposed and provisional network projects and asset-renewal projects in Zone 5, along with their projected year of completion and the factors driving the need for the projects, are listed below.

Zone 5 includes the counties of:
  • Kenosha, WI
  • Milwaukee, WI
  • Ozaukee, WI
  • Racine, WI
  • Washington, WI
  • Waukesha, WI

Zone 5 Planned Projects

Project DescriptionProject #In-service yearNeed driver
Mount Pleasant Tech Interconnection Project12019T-D interconnection
Juneautown SS, new T‑D interconnection rebuild22020T-D interconnection
State Line SS, new DIC32020T-D interconnection
Paris - Burlington 138-kV line (8962), rebuild42021Condition and performance
Port Washington SS - Saukville SS 138-kV line (762), rebuild to a double circuit52021Reliability
St. Lawrence‑Barton‑Auburn 138‑kV lines (8032/9752), partial rebuild62021/2022Condition and performance
Summit - Cooney 138-kV line (6431), rebuild72023Condition and performance

Zone 5 Proposed Projects

Project DescriptionProject #In-service yearNeed driver
Arcadian SS, power transformer and control house replacement and asset renewal82023Condition and performance

Zone 5 Provisional Projects

Project DescriptionProject #In-service yearNeed driver
None
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