Jefferson County, WI — Solar Development Risk Assessment

No Moratorium

County board passed solar zoning amendment 2023 after years of debate; accessory structure setbacks apply; permit required for ground-mounted systems >1 acre

Jefferson County: CUP in Agricultural/Industrial district for projects <100 MW.

Generally receptive — growing suburban fringe; agricultural community

SE WI; Watertown area; suburban Milwaukee fringe; active solar in agricultural areas; local CUP

Stable

PSC of Wisconsin has siting authority for wind/solar ≥100 MW (Wis. Stat. §196.491). Projects <100 MW: local CUP/SUP under county/town zoning governs. Local restrictions on wind systems must meet one of 3 conditions: (1) public health/safety; (2) not significantly increase cost/decrease efficiency; (3) allows comparable alternative. Local solar restrictions face similar reasonableness standard. No statewide preemption below 100 MW threshold — strong local control. MISO interconnection territory statewide.

Wisconsin RPS: 10% renewable by 2015 (met — weakest in region). Focus on Energy program: commercial/industrial rebates for solar ($150-450/kW for ≤25 kW). Property tax exemption: Wis. Stat. §70.111(18) — solar systems exempt from property tax assessment. Sales tax exemption: Wis. Stat. §77.54(57m) — solar equipment purchases exempt. Wisconsin Green Energy program: voluntary renewable program through WPS, MGE, We Energies. Alliant WPL (WI) has deployed ~1,089 MW solar by 2024; Vista Sands (1,315 MW Portage Co.) approved June 2025 — largest WI solar project. Utility: We Energies (WEC) serves SE WI/Milwaukee; WPS (WEC) serves NE WI; Alliant Energy (WPL) serves central/southern WI; MGE serves Madison metro; Xcel NSPW serves far NW WI; Dairyland Power Coop and WPPI Energy serve rural areas.

Koshkonong Solar Energy Center | 300 MW PV + 165 MW BESS | Jefferson/Dane County | Invenergy | PSCW approved April 2022 | WEC/MG&E purchasing output

Proposed solar ordinance returned to committee Oct 14 2025 — effectively delayed development. Concerns that 25% prime-soil threshold would effectively preclude most sites in Jefferson County. State law §66.0401(1m) constrains how restrictive ordinance can be. Sources: CitizenPortal.ai Oct 15 2025