Public Service Commission of Wisconsin Approves Minor Siting Adjustment for Koshkonong Solar Energy Center

The Public Service Commission of Wisconsin has approved a minor siting adjustment for the Koshkonong Solar Energy Center, allowing the project to move forward with modifications to its project layout. The revision involves relocating the Gen-Tie Line to the Rockdale substation and adding an additional transmission structure. The change will result in a small increase in land cover impacts but still constitutes a net reduction compared to the original application.

Key Takeaways:

• The Public Service Commission of Wisconsin approved a minor siting adjustment for the Koshkonong Solar Energy Center, allowing the project to proceed with modifications to its project layout.
• The revision involves relocating the Gen-Tie Line to the Rockdale substation and adding an additional transmission structure, which will result in a small increase in land cover impacts.
• The change will still constitute a net reduction in impacts compared to the original application.
• The applicants stated that the proposed modifications do not affect resources not discussed in the Environmental Assessment, nor do they affect new landowners who have not been given proper notice and hearing opportunity.
• The applicants ensured that landowners adjacent to parcels owned by American Transmission Company (ATC) have been notified of the proposed modification.
• The Wisconsin Department of Natural Resources (WDNR) was provided advance notice of the proposed modification on August 19, 2025.

Statistics:

• The proposed adjustments to the project layout are depicted in Exhibit 1 (PSC REF#: 563826).
• The modifications required to connect the Gen-Tie Line to the Rockdale substation include relocating the Point of Interconnection, adding an additional transmission structure, and relocating the Gen-Tie Line Right of Way.
• The total acreage disturbed remains the same, and the overall impacts still constitute a significant net reduction from the CPCN application.
• 210 feet is the distance by which the Point of Interconnection was relocated by American Transmission Company (ATC) to the Southernmost bay at the Rockdale substation.

Sources:

• Public Service Commission of Wisconsin: Re: Application for a Certificate of Public Convenience and Necessity of Koshkonong Solar Energy Center LLC to Construct a Solar Electric Generation Facility in the Towns of Christiana and Deerfield, Dane County, Wisconsin 9811-CE-100
• Wisconsin Department of Natural Resources (WDNR)
• American Transmission Company (ATC)