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Towns of Watertown, Ixonia, Farmington, and Concord, Jefferson County, Wisconsin
Docket ID: 9823-CE-100
Application for a Certificate of Public Convenience and Necessity of Sinnissippi Solar Energy LLC to Construct a Solar Electric Generation Facility Generating up to 100 MW, a Collector Substation, and a 138 kV Generator Transmission Tie Line in the Towns of Watertown, Ixonia, Farmington, and Concord, Jefferson County, Wisconsin
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Application Summary
Overview
Sinnissippi Solar Energy LLC (Sinnissippi Solar or the applicant), a wholly owned subsidiary of Invenergy Solar Development North America LLC, is seeking approval to construct a solar energy generating facility with a generating capacity of 100 MWac (megawatt alternating current) in the towns of Watertown, Ixonia, Farmington, and Concord in Jefferson County. The entire project study area that was evaluated is approximately 2,104 acres, of which, the proposed project arrays make up 558 acres, and the alternative project arrays make up 365 acres. The project substation, and ancillary facilities including access roads, generation tie line, and operations and maintenance building would require approximately 110 acres. The major components of the proposed project include solar photovoltaic (PV) panels, power conversion units, inverters, approximately 25 miles of underground 34.5 kilovolt (kV) collector circuits, a 138 kV collector substation, a newly-constructed 138 kV gen-tie transmission line of approximately 0.8 miles in length, and an operation and maintenance building. Sinnissippi Solar is seeking a Certificate of Public Convenience and Necessity (CPCN) and all other approvals required to construct the 100 MWac project, collector substation, gen-tie line, and other necessary related facilities.
Applicant Stated Need
This project is proposed by an independent power producer. Therefore, the need for the project is not reviewed by the Commission.
Estimated Cost
This project is proposed by an independent power producer. Therefore, the Commission does not review the project cost. The cost to Wisconsin utilities, and ratepayers, would be reviewed if the facility or power from the facility is purchased by Wisconsin utilities.
Project Location
The towns of Watertown, Ixonia, Farmington, and Concord, Jefferson County, Wisconsin.
Proposed Schedule
- The applicant submitted the application to the Commission in December 2025.
- If approved, the applicant anticipates construction for this project to begin in April 2027 with an estimated completion date of December 2028.
The proposed project is categorized as a
Type II action under
Wis. Admin. Code § PSC 4.10(2). The Commission will prepare an Environmental Assessment (EA) for this project that will evaluate the location of the project and its potential environmental, community, and private property impacts. There will be a preliminary determination when the EA is complete that will determine whether the preparation of an Environmental Impact Statement (EIS) is necessary.
Key Application Documents
Access Docket 9823-CE-100 in the PSC Case Management System to view additional information.
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Access Docket 9823-CE-100
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