American Transmission Co. projects

Project website for a Wisconsin-based company that owns and operates the high-voltage electric transmission system that powers communities in portions of the Upper Midwest.

Silver Maple Solar Interconnection Facilities Project

Project overview 

ATC is building interconnection facilities and performing network updates to connect the new Silver Maple Solar generating facility to the electric grid. The approximately 200-megawatt solar facility will be constructed in the towns of Eldorado and Rosendale in Fond du Lac County, and the town of Nekimi in Winnebago County. 

This ATC project includes: 

  • Building a new 345,000-volt Eldorado Substation in the town of Eldorado (north of the village of Rosendale). 
  • Looping an existing 345-kV power line that runs from the Fitzgerald Substation to the South Fond du Lac Substation into the newly constructed Eldorado Substation.
  • The installation of approximately 3.4 miles of underground fiber between the existing 138-kV power line and the newly constructed Eldorado Substation. 
  • Performing network upgrade work that includes rebuilding the existing 138-kV power line from the North Fond du Lac Substation to the Aviation Substation (both located in the city of Fond du Lac), and from the Aviation Substation to the Ellinwood Substation (located in the city of Oshkosh). 

Need for the project 

The Public Service Commission of Wisconsin approved the Certificate for Public Convenience and Necessity application for the Silver Maple Solar generating facility in March 2024. The Silver Maple Solar Interconnection Facilities Project is needed to reliably serve the new generator interconnection request for the Silver Maple Solar generating facility and allow for the generator to supply its full generator capacity to the electric grid. 

The estimated cost of the Silver Maple Solar Interconnection Facilities Project is anticipated to be $92 million. Over the lifespan of the project, the cost is disseminated through electric rates to the five million customers located in ATC’s service area.  

Additional information can be found on the PSCW website, under docket number 137-CE-208. 

Submitted application to PSCW April 2024
Anticipated PSCW project approval May 2025
Construction begins May 2026
Project in service November 2027
Restoration Q1 2028
*Dates are anticipated and subject to changes

Why is this project necessary?

The project is necessary to connect to the electric grid a new solar energy generating facility that will be constructed in Fond du Lac and Winnebago counties The PSCW approved construction of the approximately 200-MW Silver Maple Solar generating facility in March 2024.

Who decides if a project is needed?

The PSCW is the regulatory agency with the authority to approve or deny a project.  

How do I provide input to the PSCW about the project?

You can provide comments to the PSCW, either electronically or in writing under docket number 137-CE-208. You may also attend a public hearing and make your statements for the PSCW record 

Who do I contact if I have questions or comments about the project?

If you have additional questions about the project or would like to discuss it in more detail, please contact Kurt Hendrickson with ATC Local Relations at (920) 338-6515 or