Major projects update

Arcadian SS – Power Transformer and Control House Replacement and Asset Renewal

The Arcadian Substation Rebuild Project consists of 138-kV and 345-kV asset renewals of early 1970s vintage equipment and the reconfiguration of the 345-kV bus from a straight bus to a breaker-and-a-half. The project is designed to: (1) address asset renewal needs by replacing obsolete and/or poorly performing equipment; (2) improve reliability performance and operational flexibility; (3) conform to industry best practices; and (4) efficiently provide for future transmission needs.

The cost of the project is estimated to be $56.5 million and includes:

Asset renewals
- Control house
- One power transformer and retirement of two power transformers
- 24 relay panels
- 11 – 345-kV circuit breakers
- Eight – 138-kV circuit breakers
- 29 – 345-kV disconnect switches
- 13 – 138-kV disconnect switches
345-kV bus reconfiguration from straight bus to breaker-and-a-half

An application was filed with the Public Service Commission of Wisconsin in November 2020. Construction started in April 2022. The project is scheduled to be in service in 2025.    

Cardinal-Hickory Creek Transmission Line Project

ATC, ITC Midwest LLC, and Dairyland Power Cooperative are constructing the Cardinal-Hickory Creek Transmission Line Project — an approximately 102-mile long, 345‑kV transmission line connecting Dubuque County, Iowa, to Dane County, Wis. The Public Service Commission of Wisconsin approved the project in September 2019. The United States Rural Utilities Service issued a Record of Decision for the project in January 2020 and the Iowa Utilities Board issued a franchise for the Iowa portion of the project in May 2020.

The Cardinal-Hickory Creek project is one of 17 multi-value projects approved by MISO in 2011. Studies conducted initially and since that time indicate that the project will deliver benefits to local communities and the Midwest region by:

Connecting the electric transmission system in the Upper Midwest.
Allowing renewable energy generation to be delivered across the region. As of Oct. 10, 2023, there are 161 renewable generation projects dependent upon the construction and operation of Cardinal-Hickory Creek.
Providing $23 million to $350 million in net economic benefits to Wisconsin customers, and
Improving local and regional electric system reliability.

Construction began in Iowa in April of 2021 and in Wisconsin in November of 2021. The segment of the project from Hill Valley Substation near Montford, Wis., to Cardinal Substation in the town of Middleton, Wis., is expected to be in service by December 2023, and the segment from Hickory Creek Substation in Dubuque County, Iowa, to Hill Valley Substation by June 2024.

Granville – Bluemound Corridor Rebuild

The Granville to Bluemound 345-kV/138-kV Rebuild Project has four primary need drivers. These need drivers include:

Address facility age and condition issues
Address NERC contingency related reliability concerns
Address the adverse Market Congestion impacts of the corridor facilities
Increase the transfer capacity of the corridor to address Generator Interconnection and Load Interconnection needs

The project consists of the following:

Granville – Bluemound corridor rebuild to include an additional 345-kV outlet out of Granville Substation and a replacement of existing 138-kV transmission line facilities. Alternatives are being explored.

The project is currently submitted as a MTEP 2023 Appendix B project and is preliminarily scheduled to be in service in December 2028.

Howards Grove SS – Erdman SS 138 kV, new line

The construction of a new 138-kV transmission line in eastern Wisconsin, along with associated substation work, was approved by the Public Service Commission of Wisconsin in April 2022 at a cost of $28 million. The new line will address reliability concerns in Sheboygan County and the surrounding area.

The Howards Grove-Erdman 138-kV line project consists of the following:

Construct a new 7.3-mile 138-kV line from the Howards Grove Substation to the Erdman Substation
Expand Howards Grove 138-kV Substation to a 4-position ring bus
Reconfigure the Erdman 138-kV Substation to accommodate the new line

The project was placed into service in August 2023.

Marquette County Reactive Power Project

The Marquette County Reactive Power Project will provide dynamic reactive power support to the Marquette County region by installing a +/- 50-MVAr STATCOM at National Substation. Due to the lack of dynamic reactive power resources in this area in general, many loads experience high pre-contingency voltages and low post-contingency voltages. This project addresses these issues.

The project includes:

Relocate one 138-kV line position to a different bus position at National Substation
Install one +/- 50 MVA, 138-kV STATCOM (Static Synchronous Compensator) at a new site and connect at National Substation

The in-service date is anticipated to be November 2024.

Milwaukee Area 230- kV Conversion to 345 kV Project

The Milwaukee Area 230 kV Conversion To 345 kV project has the following primary need drivers:

Address facility age and condition issues,
Provide one high voltage standard of 345 kV, while streamlining needed spares, maintenance considerations, etc.,
Increase the transfer capacity of the Zone 5 transmission system to address Generator Interconnection and Load Interconnection needs,
Address NERC contingency related reliability concerns.

The project consists of the following:

Rebuild Bluemound 230 kV bus as a 345 kV ring bus,
Rebuild and/or reconductor the Oak Creek to Bluemound 230 kV lines to 345 kV, reterminate lines,
Add a 345 kV rung to Arcadian SS to loop in one of the rebuilt/converted lines,
Reconfigure the Elm Road 345 and Oak Creek 138 kV buses to add a third 345/138 kV transformer,
Allow retirement of all 230 kV facilities, Alternatives are being explored.

The project is currently submitted as a MTEP 2023 Appendix B project and is preliminarily scheduled to be in service in December 2028.

North Central Wisconsin Reliability Project

The need for this project is to improve the reliability in the north central Wisconsin region, specifically the 115-kV networked system. The proposed project will provide an additional source at the southern end of the 115-kV system, significantly improving area reliability. This will also provide significant operational flexibility and provide positive economic benefits.

The project consists of the following:

Providing a fourth 115-kV source into the Rhinelander loop between the Hilltop and Pine substations
Performing lifecycle asset renewal on relays at the Hilltop, Maine and Pine substations
Expanding the bus at the Pine Substation to accommodate an additional line terminal and upgrade the bus to match the rating of the new line

The project is scheduled to be in service in June 2028.

Perch Lake – National 138-kV Partial Retirement Project

This project was identified as an alternative to asset renewal work on the northern section of the 138-kV transmission line between the Perch Lake and Presque Isle substations in the Upper Peninsula of Michigan. The scope includes:

Terminate line into the National Substation
Establish a new 138-kV line between the Perch Lake and Presque Isle substations
Install new 138-kV breaker terminal at the National Substation.
Retire the remaining 23 miles of 138-kV transmission line between National Substation and Presque Isle Substation.
Perform Perch Lake Substation asset renewal.

The line reconfiguration is scheduled to be completed in 2025. The line retirement activities are scheduled to be completed in 2027.

Plymouth Reliability Project

The Plymouth Reliability Project is a new 138‑kV transmission-to-distribution interconnection needed to serve the expansion of a pipeline pumping facility near the Town of Mitchell, Wis. In addition to serving the load addition at the pumping facility, this project will also improve Plymouth Utilities reliability by transferring load from an existing Plymouth Utilities substation and improve contingency backup capabilities.

The cost of this project is estimated to be $31.0 million and included the following:

New 138-kV/12.47-kV interconnection substation to be named the Plymouth 5 Substation.

New double-circuit 138-kV transmission line approximately 8.0 miles in length from the Saukville-Elkhart Lake 138-kV line to loop in and out of the new Plymouth 5 Substation.
Plymouth Utilities will install two distribution transformers with this project.

A Certificate of Public Convenience and Necessity (CPCN) application is being developed and will be submitted to the Public Service Commission of Wisconsin in early 2024.

Racine County T-D Interconnect Project

The Racine County T-D Interconnection Project is a new 138‑kV transmission-to-distribution interconnection needed to serve a new load addition in southeast Wisconsin. This project has an accelerated schedule with an early 2025 in-service date and will require a MISO Expedited Project Review, which we expect to submit in late 2023.

The project consists of the following:

New 138-kV/24.9-kV interconnection substation to be named Nimbus Substation
Two short double circuit 138-kV transmission lines between the Mount Pleasant and Nimbus substations
Expansion of the Mount Pleasant Substation to accommodate new 138-kV transmission lines and a new 500 MVA 345-kV/138-kV transformer
New FACTS device at Mount Pleasant Substation to support the transmission system

Rock County Reliability Project

The Rock County Reliability Project is urgently needed to address increasingly difficult re-dispatch scenarios and avoid increasing the risk of customer outages. It also will support preparations to address Paddock Substation asset renewal needs in the planning horizon.

The project includes the following activities:

Expanding the Kittyhawk Substation by adding a 138-kV substation and two 345-kV/138-kV transformers
Looping the Bass Creek-Townline Road line into the Kittyhawk 138-kV bus
Looping the Paddock-Townline Road line into the Kittyhawk 138-kV bus
Building a third Kittyhawk-Townline Road 138-kV Line
Uprating the Townline Road – Rock River 138-kV line
Rebuilding a portion of the Rock River – Colley Road 138-kV line
Adding grounding to area substations

A MISO MTEP22 project was approved by the Public Service Commission of Wisconsin in August 2023 and is expected to be in service by the end of 2024.

Valders SS, New 138/69 kV Substation

The Valders Substation Project consists of building a new 138-kV/69-kV substation to improve reliability in the Manitowoc area. The new substation will connect a 138-kV transmission line that runs between the Forest Junction and Howards Grove substations and a 69-kV transmission line that runs between the New Holstein and Custer substations.

The new Valders Substation:

Relieves economic congestion in Northern Manitowoc.
Provides an additional source for Manitowoc load, enhancing operational flexibility to better manage the outage of generation or transmission for line maintenance.
Prepares the system to better address potential reliability issues related to future changes in Manitowoc area generation.
Helps to accommodate potential future local load or generation growth.

Waupaca Area Energy Storage Project

The Waupaca Area Storage Project was identified in MISO’s 2019 MISO Transmission Expansion Planning (MTEP 19) report as the preferred solution to address an identified reliability need in the Waupaca, Wis., area. MISO approved the project’s inclusion in the regional plan in December 2020. The $13.9 million project includes:

2.5MW / 5MWh battery at Harrison North Substation (and associated substation work), and
14MVAr of total capacitance at the Arnott and Harrison North substations.

The project will be installed to help address multiple transmission line outage issues and to provide additional operational flexibility. The project is estimated to be in service in early 2024.

Wells St. DIC – New West Marinette-Wells St. 69 kV line

The need for this project is driven by a new load addition in Marinette, Wis. The proposed project will address reliability issues incurred by this new load and provide operating flexibility to perform maintenance without placing area load at risk.

The project consists of the following:

Rebuild 1.6 miles of existing West Marinette – Wells St. 69-kV line as a double circuit 69-kV line
Build new 4-mile, 69-kV transmission line between West Marinette Substation and Wells St. Substation
Add 1.9 miles of new circuit to the existing structures of J62 between the Roosevelt Substation and the Wells St. Substation
Position new 69-kV bus at the West Marinette Substation
Use vacant 69-kV bus position and terminal facilities at Wells Street Substation
Install 1.0-mile underground circuit from Riser Structure to Wells St. (in spare conduit duct)

The project is scheduled to be in service in January 2024.

Winona – Atlantic 69kV Rebuild

This project is needed to support the transmission system in the Keweenaw Peninsula in Michigan’s Upper Peninsula. The proposed project will address reliability issues and provide greater operational flexibility for the region.

The project consists of the following:

Rebuilding 22.9 miles of 69-kV transmission line between the Winona Substation and Atlantic Substation
Replacing jumpers and switches at Winona Substation to meet new line rating

The project is scheduled to be in service in December 2024.

WisDOT I-94 Stadium Group of Projects

The I-94 Stadium (DOT) Milwaukee County project has three primary need drivers. These need drivers include:

Relocating and rebuilding of transmission lines and substation facilities in conflict with the proposed WisDOT I-94 East/West corridor rebuild.
Rebuilding of select ATC lines adjacent due to age and condition.
Enhancements of ATC communications along the existing corridor.

The project consists of the following:

WisDOT I-94 E/W Relocation (~1.5 miles with line routing and substation site selection to be determined)
I-94 Stadium Project Asset Renewal (~.5 miles)
I-94 Stadium Project Communications – Fiber Installation (~ 4 miles between 96th Street Substation to Valley substation.)

The project is currently scheduled to be in service in early 2028 but will be coordinated with WisDOT’s work. All work is included in MTEP 2022 Appendix A as one project.